The Microscope in American Medical Science, 1840-1860

The Microscope in American Medical Science, 1840-1860Author(s): James H. CassedySource: Isis, Vol. 67, No. 1 (Mar., 1976), pp. 76-97Published by: The University of Chicago Press on behalf of The History of Science SocietyStable URL: http://www.jstor.org/stable/231135 .

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The Microscope in American

Medical Science, 1840-1860

By James H. Cassedy*

SCATTERED MICROSCOPES were to be found in the cabinets of American colleges and learned men of the eighteenth century at least from the days

of Cotton Mather. But none of them, so far as has been discovered, were ever seriously used in scientific investigation. In this country as everywhere, after the original seventeenth-eighteenth century flurry of microscopic discovery, these instruments were really little more than expensive playthings of the curious or well-to-do. The device which, in the hands of men like Leeuwen- hoek, Hooke, and Malpighi, had led to such great excitement in the biological and medical sciences, seemed to lead subsequent investigators mainly to a blank wall.'

John Crawford of Baltimore in 1808 regretted that the pursuit of microscopic research had been "nearly dormant . . . for more than half a century," and he hoped that it could be soon revived.2 However, baffling technical difficulties stood in the way of such a revival during Crawford's lifetime. The New York physiologist John C. Dalton, who lived sufficiently later to profit from the resurgence when it occurred, in 1856 summarized the problems as they had existed before his generation:

The compound microscope, indeed, was almost useless, owing to the serious and apparently insurmountable difficulties of spherical and chromatic aberration. Nearly all the truly valuable discoveries of the older microscopists had accordingly been made with the simple microscope, and the limited capacity of this form of the instrument being more or less exhausted, microscopic investigation seemed to be

Received October 1973: revised/accepted December 1974. *National Library of Medicine, National Institutes of Health, Bethesda, Maryland 20014. 'There is still no adequate general history of American microscopy. Most accounts have been

discussions of the technical and commercial development of the microscope in America and catalogues of instrument collections. The most useful works for this study include Simon Henry Gage, "Microscopy in America (1830-1945)," Transactions of the American Microsocopical Society, 1964, 83, No. 4 (Supplement): 1-125; Harold F. Schaeffer, "Nineteenth Century American Microscopy," The Microscope and Crystal Front, 1965, 14:464-469, 471-481; D. H. Wenrich, "Some American Pioneers in Protozoology," Journal of Protozoology, 1956, 3:1-7;, The Billings Microscope Collection of the Medical Museum, Armed Forces Irstitute of Pathology, ed. Helen R. Purtle (Washington, D.C.: American Registry of Pathology, 1967); Three American Microscope Builders (Buffalo: American Optical Co., 1945). Published too late to be of use in this paper was Donald L. Padgitt, A Short History of the Early American Microscopes (London/Chicago: Microscope Publications, 1975).

2John Crawford, "Observations on the Seats and Causes of Diseases," Baltimore Medical and Physical Recorder, 1808 / 1809, 1:86.

76



THE MICROSCOPE IN AMERICAN MEDICAL SCIENCE 77

arrested by a natural barrier that offered but little prospect of ever opening a way to further prosecution of the science.3

The handful of eighteenth-century Anierican scientists who interested themselves in theoretical optics, men such as James Logan and David Rittenhouse, made no special contribution to these practical problems. And little help came from the tiny number of instrument makers and lens grinders who were beginning to appear in coastal cities late in that century and in the early decades of the nineteenth.4 However, by the 1820s the efforts of a number of European optical workers finally produced achromatic lenses which effectively overcame the worst of the aberration problems. This breakthrough was, of course, directly responsible for large parts of the proliferating scientific knowledge of the remainder of the nineteenth century. European and British scientists, backed by substantial numbers of firmly established scientific institutions and by a solid existing capacity for manufacturing optical instruments, were able to exploit the new discovery relatively quickly. As early as 1830, rising young scientists such as Louis Agassiz were launching their careers by purchasing achromatic microscopes; and by the end of another decade, in Germany alone, the new instruments had made possible such contributions as the microzoological classifications of Christian Ehrenberg and the revelations of cell structure by Schleiden and Schwann.

American adoption of the achromatic microscope, like the emergence of chemical laboratories, trailed European developments by more than a decade. Accordingly, biomedical science on this side of the Atlantic continued for some time to be largely dependent upon the foreign work. With respect to microscopy, the delay was no more than was to be expected, given the primitive state of American optical technology and the negligible optical industry, together with the small size, relative feebleness, meager facilities, and paucity of funds of virtually all American scientific and educational institutions prior to 1830.5 Nor was there any great enthusiasm for microscopy among American scientists until their European teachers set the example.6 While the Americans Edward

3J. C. D. [John C. Dalton], review in American Journal of Medical Science, 1856, N.S. 32:397 ff. For a general history of the microscope (but with little on nineteenth-century American developments), see S. Bradbury, The Evolution of the Microscope (Oxford: Pergamon Press, 1967). An excellent recent examination of the impact of the microscope on European embryological study is Charles W. Bodemer, "The Microscope in Early Embryological Investigation," Gynecological Investigation, 1973, 4:188-209. Broader in scope and even more relevant to the present study, though also dealing solely with the European scene, is R. H. Nuttall, "The Achromatic Microscope in the History of Nineteenth Century Science," The Philosophical Joumnal, 1974, 11:71-87. A recent general work is Hugo Freund, " 150 Jahre Entwicklung der Mikroskopie im Uberblick," Microscopica Acta, 1974, 76:105-112, 209-215.

4Silvio Bedini has identified two craftsmen who were active in Britain's mainland American colonies as makers of optical instruments before 1760 and some half dozen others between 1793 and 1801. See Silvio A. Bedini, Early American Scientific Instruments and Their Makers (Washington, D.C.: Smithsonian Institution, 1964), pp. 27-31.

5The condition of the native optical trade and industry from 1785 to 1840 needs further study. 6However, Michael Faraday pointed out one advantage of the microscope which should have

made it attractive to scientists of his day: "He who studies chemistry by microscopical experiments, testing the qualities rather than ascertaining the quantities of matter, may find a cupboard sufficient



78 JAMES H. CASSEDY

Thomas and Alden Allen approached the problem of fashioning achromatic lenses before 1830, American success in this aspect of optics had to wait until the late 1840s.7 Meanwhile, during the 1830s and more extensively in the 1840s, American scientists and physicians were introduced to the use of European achromatic instruments and began applying them to various research problems. Those who had both the money to buy microscopes and the leisure to use them became, by their small number if nothing else, a very elite group in Jacksonian America; and a good microscope even became a tangible status symbol in scientific circles. For the general public, a good microscope seemed almost as much of a curiosity as the mastodon or the Siamese twins. At least, large crowds were reported paying to view one of the instruments that was exhibited in New York City by Rubens Peale during the mid-1830s at his museum on Broadway.8

Not surprisingly, many of the earliest Americans who applied microscopy seriously were those devoted to one or more aspects of natural history. In fact, one of the pioneer centers of American microscopy in the early 1840s was the United States Military Academy at West Point, or, more accurately, the scientific activity of Jacob W. Bailey. As Professor of Chemistry, Mineralogy, and Geology, Bailey travelled around the eastern United States gathering specimens from waterways and mountain passes, made preliminary microscopic observations of his own, sent speciments to Europe, and checked his classifications with English and continental scientists, particularly Ehrenberg. Though himself virtually self-trained, Bailey guided some of his American scientific colleagues in the use of European instruments, and did it so well that he eventually became known as the "Ehrenberg of America."9

Conspicuous among these colleagues was the botanist John Torrey, who invariably went to Bailey for help in adjusting his new microscopes.'0 In turn, Asa Gray got his early experience in microscopy from Torrey, but he far outdistanced his teacher by the instruction he absorbed during a European trip of 1838-1839. Commissioned to buy microscopes in Europe for a number of American observers, Gray learned there to discriminate between the merits of the various lenses and instruments by attending some of the "microscopical

for his operations, or may even pack all his requisites on a tray; whilst the person who is engaged in metallurgical processes, in extensive experiments on gaseous matter, or in the application of chemistry to the arts, will find a laboratory essential." Michael Faraday, Chemical Manipulation, ed. John K. Mitchell (Philadelphia: Carey & Lea, 1831), p. 17.

7Edward Thomas, "On Improvements in the Microscope," American Joumnal of Science, 1830, 19:57-61. Thomas, formerly an engineer on the Cayuga and Seneca Canal, attributed the first effective European achromatic microscope to the one built in 1824 by W. Tully for Dr. C. R. Goring.

8This instrument belonged to Robert H. Collyer, an English physician who was in the United States between 1836 and 1843. See Robert H. Collyer, Lights and Shadows of American Life (Boston: Redding, 1844?), p. 15.

9The term was applied by A. A. Gould, in his "Address in Commemoration of Professor J. W. Bailey," Am. J. Sci., 2nd Ser. 1858, 25:157. See also the articles and reviews by Bailey during the 1840s, especially those in the American Joumnal of Science.

I0Andrew Denny Rodgers, III, John Torrey: A Story of North American Botany (New York: Hafner, 1965), pp. 125, 213, and passim.




parties" which were so fashionable in London and by getting English and continental scientists and manufacturers to demonstrate their instruments. In Florence, after calling on the microscopist C. B. Amici, Gray wrote back to America that Amici thought his instruments to be "unrivaled, but I don't." I

In Bailey's office at West Point in 1839, Torrey examined a new microscope which had just come in, Raspail's best, but concluded that it did not measure up to another French instrument, that of Chevalier. "We must take measures," he wrote to Gray, "to have a supply of Chevalier's instruments kept here [in the United States] -for many botanists would get them at once if they knew where to find them."'12 By the mid-1840s, as increasing numbers of American natural history investigators were trying to obtain quality microscopes, Benjamin Silliman summarized the general appreciation of what the instrument was doing for these sciences:

The microscope has revealed to us the intimate and concealed structure of fossil plants-of petrified trees, whose delicate vessels had been filled with mineral matter . . .or whose substance had been converted into coal; we discern the fibres and tissue of primeval forests converted into stone; their resins and gums stored away in the dark beds of coal are now, as it were anew. . . The microscope has brought the most signal aid to comparative anatomy; by its assistance, thin sections of both fossil and modern teeth and bones are compared, and thus analogies and contrasts are estimated between the ancient and the recent races of animals. . . . The microscope . . . has not only passed in review the living infusorial animalculae, but has penetrated the veil that concealed the fossilized races, whose existence had not been even suspected.13

While leading naturalists greeted the achromatic microscope with enthusiasm, medical men seemed to be of two minds about it. American medical students of the 1 830s and early 1 840s found that most of their texts treated the microscope and its findings "with distrust and even with contempt," if indeed they mentioned them at all. Typical among these were such popular English works as the Bells' anatomy text and Bostock's physiology. 4 In France, anti-microscopism was strong among the Paris clinicians, and this attitude rubbed off on many Americans who studied there. In addition, certain of the old school medical

" Quoted in A. Hunter Dupree, Asa Gray, 1810-1888 (Cambridge, Mass.: Harvard University Press, 1959), pp. 74, 83-87.

'2Rodgers, John Torrey, p. 125. 3Benjamin Sillirnan, "Address before the Association of American Geologists and Naturalists,

assembled at Boston, April 24, 1842," Am. J. Sci., 1842, 43:219-220. 14See Oliver Wendell Holmes, "An Address Delivered at the Annual Meeting of the Boston

Microscopical Society," Boston Medical and Surgical Joumnal, 1877, 96:602. The Bells, for instance, while they devoted three pages in 1827 to discussing previous researches on the "minute" (microscopic) structure of the brain, felt that even that was more than was deserved, for they were convinced that there was no "hope of the subject proving useful." John and Charles Bell, The Anatomy and Physiology of the Human Body, John D. Godman, ed., 2 vols. (5th American ed., New York: Collins, 1827), Vol. II, pp. 41-43. See also John Bostock, An Elementary System of Physiology (4th ed., London: H. G. Bohn, 1844). Similarly, Samuel D. Gross, in the first edition of his Elements of Pathological Anatomy, 2 vols. (Boston: Marsh, Capen, Lyon, & Webb, and James B. Dow, 1839), almost totally neglected the microscopic studies of the 1830s in favor of earlier works, though by the third edition (1857) he was relying considerably on more up-to-date research.



80 JAMES H. CASSEDY

theorists recognized the new instrument as a threat to their a priori systems. One of this group, Martyn Paine of New York, in 1840 found it desirable to attach a twelve-page appendix to his Medical and Physiological Commentaries to argue how unreliable and misguided miscroscopic research really was. After ridiculing the work of Ehrenberg and some of the American geologists, he passed microscopy off as merely a transitory fad, one to be treated like other fads such as animal magnetism. "We think it may be safely affirmed," he wrote, "that the microscope has not added to our knowledge a solitary fact of practical use to atone for the evils which it has inflicted." 5

That Paine was not alone in this opinion is attested to by John Hiester, who noted in 1844 that microscopes were thus far only infrequently used in anatomical or pathological research in the United States.16 As late as 1848 the Philadelphian Alfred Stille, like many other physicians, found the use of microscopes so complicated that it led him to suggest that physicians would find

. . .more profitable occupation in investigating the relationships of phenomena cognizable by the senses.. . . The use of the microscope in pathological investigations is an art so difficult, that none but those who have especially, and for a long time, cultivated it, can depend upon the correctness of their observations, or estimate justly the phenomena they witness. On this account it can never become . . . of habitual employment in ordinary practice.'7

It was thus entirely understandable that through the 1840s scientific method in medicine was much more often understood to mean medical chemistry, medical statistics, or medical observation generally than it did microscopic research.

However, from the 1830s at least a handful of American physicians were aware that the instrument did indeed have an important place in medicine. As early as 1832 Samuel Jackson of Philadelphia was incorporating European microscopic findings in his text on The Principles of Medicine; he substantiated some of the findings with his own instrument. William Beaumont, in the course of his experiments on Alexis St. Martin, made a series of microscopic examinations of gastric juice and of various objects in the stomach, though the findings did not add much to his study of digestion. John L. Riddell of Cincinnati, in his 1836 "Memoir on the Nature of Miasm and Contagion," published four

15Martyn Paine, Medical and Physiological Commentaries, 2 vols. (New York: Collins, Reese & Co., 1840 and 1844), Vol. I, pp. 707, 709. In 1832 Paine performed one of the first American autopsies on a cholera victim, but apparently he did not use a microscope. Long, History of Pathology, pp. 58-59. For the Parisian attitudes, see Erwin H. Ackernecht, Medicine at the Paris Hospital 1794-1848 (Baltimore: Johns Hopkins Press, 1967), pp. 8-9, 122-126.

16John Hiester, letter to editor, Boston Med. Surg. J., 1844, 30:108. 17The principal value of the microscope as then perceived by Stille was its use in morbid anatomy,

i.e., in certain phases of autopsies, but he did not indicate to what extent this application was being made in the United States. Alfred Stille, Elements of General Pathology (Philadelphia: Lindsay & Blakiston, 1848), pp. 104, 198. Likewise, the standard history of American pathology sheds little light on this matter: Esmond R. Long, History of American Pathology (Springfield, Ill.: Thomas, 1962).




years before Jacob Henle's famous work on the subject, used the findings of Ehrenberg, Muller, and other European microscopists as the basis for his belief that microorganisms were the likely causes of infectious diseases. He urged other Americans to replace vague theorizing by microscopic research, and he began microscopic work of his own which was ultimately of some significance. Similarly, in Philadelphia, John K. Mitchell in the early and mid-1840s built his entire theory of the fungous origin of epidemic fevers upon the evidence provided by European microscopic researches. Mitchell never completed the experiments by which he hoped to prove his theory, but Bailey told him he felt the theory was so thoroughly based in science as to encourage further experiment by others.18

Oliver Wendell Holmes, who pursued medical studies in Paris between 1833 and 1835-when Paris was at the peak of its renown as a center of medical advance-could "not remember ever hearing one word [there] about the microscope or the results obtained from its employment." Nevertheless, he took back with him to the United States, almost as a curiosity, a simple microscope by Raspail. In the next few years, as he could afford them, Holmes acquired better instruments: by 1847 he owned two good-quality compound French achromatic microscopes, one a Chevalier and the other an Oberhauser. He went on, during the two decades before the Civil War, to become a major figure in advancing both the use and the technology of the microscope. He read papers and gave demonstrations to medical and natural history groups, introduced new European instruments, and encouraged native American microscope developers and manufacturers of optical instruments. Perhaps most significant for medicine, by the early 1840s he had begun instructing his Boston medical students in the use of the microscope, an example that by 1860 was being followed in many if not most American medical schools.'9

A sprinkling of other physicians were also acquiring and utilizing microscopes during the 1830s and 1840s. In Philadelphia, William E. Horner, who had had an instrument as early as 1832, was lecturing in 1843 on the application

18Samuel Jackson, The Principles of Medicine (Philadelphia: Carey & Lea, 1832), esp. pp. 15-17, 23, 459-461; John L. Riddell, "Memoir on the Nature of Miasm and Contagion," Westemn Journal of the Medical and Physical Sciences, 1835/36, 9:401-412, 526-532; and see discussion on Riddell in James H. Cassedy, "John L. Riddell's Vibrio biceps: Two Documents on American Microscopy and Cholera Etiology 1849-59," Joumnal of the History of Medicine, 1973, 28:101-108. Mitchell presented his theory for several years to his students before publishing it under the title On the Cryptogamous Orgin of Malarious and Epidemic Fevers (Philadelphia: Lea & Blanchard, 1849), in which see esp. pp. 38-39. Bailey's letter to Mitchell, dated Mar. 5, 1845, is quoted in the Introduction, pp. v-vi. Beaumont recorded that the examinations he made were performed with a compound microscope belonging to Professor Jones of Columbian College and in the presence of Robley Dunglison and Captain H. Smith. William Beaumont, Experiments and Observations on the Gastric Juice, and the Physiology of Digestion (Boston: Lilly, Wait, 1834), p. 233.

19For Holmes' own recollections of his microscopic career, see his "Address to the Boston Microscopical Society," pp. 601-611. Holmes recalled that his father had once purchased a magnifier or simple microscope from the Reverend John Prince of Salem (pp. 601-602). For secondary discussions of Holmes' contributions to microscopy, see Eleanor M. Tilton, Amiable Autocrat: A Biography of Dr. Oliver Wendell Holmes (1809-1894) (New York: Henry Schuman, 1947), passim, and Thomas E. Hunt and Eleanor A. Hunt, "Dr. Oliver Wendell Holmes: Teacher and Microscopist," Alabama Joumnal of Medical Science, 1966, 3:76-90.



82 JAMES H. CASSEDY

of the microscope to human anatomy. He assured listeners at the American Philosophical Society that the achromatic lens had turned the microscope into a reliable instrument of research and that few of the objections of critics like Paine were valid any longer.20 In New York, several of the faculty members at the College of Physicians and Surgeons had good instruments by 1847, and one of them, Alonzo Clark, was lecturing his classes on the instrument's use. In that same year, the editor of the New York Journal of Medicine suggested that "a good microscope has become . . . essential to the physician."'21

By this time, at least some scientists and physicians in all the larger American cities owned good microscopes-that is, compound achromatic instruments-yet ownership was considerably restricted by the costs, delays, and uncertainties involved in ordering from Europe. The American market during these years was divided almost exclusively between English and French manufacturers.22 The prestigious Ross and Powell and Lealand instruments from England were prized for their quality, but their costs were high; the popular French microscopes, on the other hand, particularly the Chevalier, the Nachet, and the Oberhauser, could not match the English instruments in power and precision, but they were simpler to handle and their prices much lower. Waldo Burnett, a brilliant young Boston physician-naturalist, who in 1851 went into some detail on the respective advantages and disadvantages of the instruments of both countries, concluded mainly in favor of the French. With a certain amount of irony he pointed up the heavy and "exquisitely wrought brass mounting" of the English instruments, which tended to turn them into immovable "fixtures" of a laboratory rather than readily usable devices. Despite the excellent English lenses, he concluded, "I cannot think their mountings so well suited for real work as some others; but they are most excellently adapted for that class of microscopists who are not desirous of being workers so much as of being amateurs in this department of science." In turn, Holmes found that the large Ross microscope which had been purchased by the Lowell Institute in the 1840s-a "mighty optical engine" costing around $600 and admirable in performance-was "as stable as the Bunker Hill monument" and had "brass enough in it for a pair of andirons." Making clear his own preference for simple instruments, he later recalled that Jeffries Wyman for years kept "a complicated and imposing microscope under a bell-glass on his table," but

20See summary in Proceedings of the American Philosophical Society, 1843, 3:89-90. As early as the epidemic of 1832, however, both Horner and John K. Mitchell had used microscopes to observe the effects of cholera in the human body; William E. Horner, "On the Anatomical Characters of Asiatic Cholera," Am. J. Med. Sci., 1835, 16; Editorial, Medical Examiner, 1849, N.S. 5:687.

21 New York Journal of Medicine, 1847, 9:401. Among other physicians who were giving instruction in the microscope by the early 1850s were Jeffries Wyman at the Hampden-Sydney Medical College in Richmond (between 1843 and 1848) and John C. Dalton at the University of Buffalo (by 1852).

22Despite extensive review and discussion in American journals from the late 1830s onward of German microscopic contributions to anatomy, physiology, and pathology, few Americans seemed to own German-made microscopes. This condition changed perceptibly only with the large wave of American students in Germany after the Civil War.




used a very plain and ordinary instrument for most everyday scientific work.23 Well into the 1 840s no native American optical manufacturer had the capability

of breaking into the still tiny American microscope market. When one did emerge, it was with the express aim of producing instruments which would combine the quality of the British models with the moderate cost of the French. In 1847 Charles A. Spencer, a self-trained instrument maker from Canastota in upper New York State, delivered his first successful achromatic microscope to the New York City obstetrician Chandler R. Gilman.24 Before the year was out scientists all over the country were clamoring to obtain their own Spencers, even before they knew for certain how this native American product performed against its European rivals.

The first word-of-mouth and journal reports of Spencer's achievement, particularly his ability to construct a lens with an extraordinarily wide angle of aperture-exceeding 1700 at a time when no European lens went beyond 1350-quickly flooded him with more orders than he could quickly fill.25 By the end of 1847 he had orders from several colleges-Princeton, Buffalo, and Geneva, among others-along with the Smithsonian Institution and many individual scientists. John L. Riddell, who had moved from Cincinnati to become Professor of Chemistry in the Medical Department of the University of Louisiana, and who was one of the earliest fortunate recipients of Spencer's lenses, quickly recognized their exceptional power and clarity of focus, "superior to anything of the kind in the Southern country." He immediately embarked on an orgy of observations, of algae, infusoria, alligator blood, pathological specimens, river water, swamp ooze, and other objects, and was so enthusiastic about his new instrument that within five years he ordered and received from Spencer a still finer set of objectives.26 In Boston Holmes owned three sets of Spencer objectives by 1852. Torrey ordered his Spencer in 1848, but had to wait two years for delivery. Joseph Henry had to wait over seven years for the Smithson- ian's instrument, but he thought it well worth the wait if the Institution's patronage would assist the native American optical industry. Like other leading

23Waldo I. Burnett, "On Microscopes and Microscopy," Am. J. Sci., 1851, 2nd Ser. 12:60-62. See also William B. Carpenter, The Microscope and its Revelations (Philadelphia: Blanchard & Lea, 1856), pp. viii, 75, and 704; and Holmes, "Address to the Boston Microscopical Society," p. 603.

24C. R. Gilman, "An Account of a Compound Achromatic Microscope, made by Charles A. Spencer of Canastota, N.Y.," Am. J. Sci., 1848, 2nd Ser. 5:237-240.

25Holmes was certain that John Quekett, in the second edition of his A Practical Treatise on the Use of the Microscope (London: Bailli&re, 1852), had chauvinistically dropped all mention of Spencer because the angle of aperture which the American had achieved was so far in excess of what the greatest English microscope maker, Andrew Ross, had declared to be possible. Holmes, "Address to the Boston Microscopical Society," pp. 609-610. For Spencer's account of the optical difficulties of producing such a lens and of his self-training during the 1840s which led up to this achievement, see "On the Improvements by Mr. Chas. A. Spencer in Microscopic Object glasses (from a letter from Mr. Chas. A. Spencer, addressed to Prof. Horsford and Dr. Burnett, published in the Boston Traveller)," Am. J. Sci., 1852, 2nd Ser. 13:290-292.

26J. L. Riddell, "Notes of Microscopic Observations," New Orleans Medical and Surgical Journal, 1849/50, 6:790-794; and John L. Riddell, "Selected Items of Microscopic Observation," New Orleans Med. Surg. J., 1852/53, 9:119. For a discussion of Riddell's observations, see Cassedy, "Riddell's Vibrio biceps," pp. 101-108.



84 JAMES H. CASSEDY

scientists, Henry was fully aware of the significance of the new instrument:

There is an article of apparatus which, within a few years past, has opened almost a new world of research in the phenomena of life and organisms, the use of which is now indispensable in advancing our knowledge of physiology and its kindred branches of science. I allude to the achromatic microscope, to increase the power of which, the artists of Germany, France, and England have vied with each other. On account of the small number of persons who are capable of constructing the proper lenses, the best specimens of this instrument are very scarce in this country, and can be procured only at a great expense. Under these circumstances, it was a matter of much interest to learn . . . that an individual in the interior of the State of New York had successfully devoted himself to the study of the microscope, and that he was able to produce instruments of this kind which would compete with the best of those constructed in Europe.27

Many of those who had to wait for delivery of their Spencer instruments doubtless did so with increasing impatience as flattering reports appeared in the American scientific journals, some of them with the results of comparative tests of the Spencer with foreign makes. Jacob Bailey, who made the first widely publicized trial, pitted Gilman's Spencer in November 1847 against "one of Charles Chevalier's largest Achromatics," and found the American instrument "far superior." During the next few years the enthusiastic Bailey went on to engage the Spencer lenses in an informal but well-publicized competition with Ross, Powell and Lealand, and other British lenses. His success in viewing increasingly difficult test objects won the admiration of some British observers as well as Americans, though others let it be known that they considered him excessively chauvinistic. Actually, Bailey's enthusiasms were readily explainable on wider grounds than patriotism. Particularly in those early days of the instrument, as Holmnes remarked, "every microscopist goes through a period of combative excitement about his objectives if he has any remarkable ones."28

In such a state of excitement, Americans remained intrigued for some time with the competitive aspects of high-power lenses; one observer in 1851 reported that native scientists were concentrating "almost universally" on such instruments. Gradually, however, it was realized that the lower powers were not only entirely satisfactory but preferable for much scientific work. Waldo Burnett, while himself fascinated with the fine points of histology and other mysteries of physiology and pathology which only increasingly powerful lenses could reveal, conceded that the moderate-cost instruments were adequate for most routine work. Moreover, "this [latter] class of instruments have certainly

27 Joseph Henry, "Report of the Secretary," Smithsonian Institution, Annual Report (1847) (Washington, D.C.: Tippin & Streeper, 1848), p. 189. Henry's acknowledgment of the ultimate receipt (1854) of Spencer's instrument, "which far exceeds that which was anticipated," is found in "Report of the Secretary," Smithsonian Institution, Ninth Annual Report (for 1854) (Washington, D.C.: Nicholson, 1855).

28J. W. Bailey to C. R. Gilman, Nov. 27, 1847, in Gilman, "Account of a Compound Achromatic Microscope," pp. 238-239. See also Bailey's further communications on this subject in Am. J. Sci., 1848, 2nd Ser. 5:285-286, and 1849, 7:265-270; together with response by Warren De la Rue, "On the Navicula Spencerii," 1850, 9:23-29. Holmes, "Address to the Boston Microscopical Society," p. 605.




done more than any other for building up microscopical science, (which is not made up of the study of test-objects)."29

However, more tests needed to be made, and they were-by local and national scientific bodies as well as individuals. Another 1847 test of the Spencer was made by a committee of the New York Lyceum of Natural History composed of John Torrey, J. F. Holton, and John L. LeConte. The committee found that "the superiority of Mr. Spencer's microscope over Chevalier's number one is very decided, although made on a much smaller and less expensive scale."30 In 1851 a committee of the American Association for the Advancement of Science subjected Spencer lenses to "numerous trials with the most difficult test objects known." With these lenses the committee reported obtaining results "which they believe have never hitherto been obtained by any microscopes in existence. The low powers, as well as the high ones, excited their admiration." Their stated conclusion was that "Spencer's objectives are now the best in the world."31

At about the same time, Holmes tested his Spencer lenses against the objective lenses from the Lowell Institute's large Ross microscope, using such difficult test objects as Navicula spencerii and Grammataphora. He thought that "the superiority of Mr. Spencer's glasses was unquestionable." Similarly, observers at a Philadelphia trial in 1851 found that in a comparison with high-quality Powell and Lealand lenses the results "seemed quite in favor of Spencer."32

Despite all of these persuasive reports, Waldo Burnett felt that a truly critical test could only take place in Europe, for the "best foreign instruments seldom reach this country. The makers have always friends at hand who immediately seize [the superior instruments]." Accordingly, while on a European trip in the fall of 1850 Burnett sought out an occasion to match his new set of Spencer lenses against some of the very best produced by European manufacturers. When such a test was finally arranged it involved Burnett's Spencer lenses, top-rated sets of lenses by Ross and by Nachet, both owned by Americans then in Paris, and a few less-than-superior samples of lenses of other manufacturers that did not really figure in the competition. The actual tests were upon "the most difficult" objects then in use: Nobert's lines, the Grammatophora

29Joseph H. Wythes, The Microscopist (Philadelphia: Lindsay & Blakiston, 1851), p. 38, and Burnett, "On Microscopes and Microscopy," p. 61.

30"Copy of the Report on Mr. Charles A. Spencer's Microscope, made to the Lyceum of Natural History," attached to Gilman, "Account of a Compound Achromatic Microscope," pp. 239-240.

31 "Report of the Committee on Microscopes, on the Lenses Exhibited to the Association by Mr. Spencer," Proceedings of the American Association for the Advancement of Science, 1852, 6:397-398. Members of the committee were Jacob W. Bailey, Waldo I. Burnett, Alonzo Clark, J. Lawrence Smith, and John Torrey.

32Oliver Wendell Holmes, "On the Use of Direct Light in Microscopic Researches," Proceedings of the American Academy of Arts and Sciences, 1848-1852, 2:326; and Burnett, "On Microscopes and Microscopy," p. 59. In 1853, at the American Medical Association meetings in New York, Holmes pitted his "most formidable objectives" (not further identified as to make), mounted on one of his own "homely wooden stands," informally against a considerable number of "showy instruments" and thought he had bettered them all. However, there turned out to be one exception. That involved the physicist Lewis Rutherfurd, "working with an instrument made by Amici, of Modena, having the first immersion objective I had ever seen, possibly the first that was ever in this country" ("Address to the Boston Microscopical Society," pp. 605-606).



86 JAMES H. CASSEDY

subtilissima, and a shell, one of the Naviculae, known as Amici's test. The two Americans who reported the event, Burnett and J. Lawrence Smith, agreed that the Nachet's performance was slightly below that of its rivals, but there seemed to be no appreciable overall difference between the Ross and the Spencer. All of those who took part in the tests went away with heightened opinions of the potentialities of the microscope generally. But Burnett could not restrain his satisfaction with the manifest "astonishment" which European observers expressed at the high performance of a native American optical instrument.33

Americans travelling in Europe prior to 1860 did not, to be sure, notice any groundswell of demand for American microscopes; European microscopic nationalism was as well developed as the American variety. In fact, only one Spencer was known to be in England up to 1856, though F. P. Porcher of Charleston also found a set of Spencer's lenses in Amici's Florence laboratory in 1854. Amici acknowledged Spencer's skill as an artist, but declared to Porcher that Spencer's lenses did not have "the power and clearness of his own."34

At home, however, the introduction and success of the Spencer instrument proved to be a great source of national scientific pride. Editors of scientific and medical journals across the country were lavish in their praise of Spencer's achievement, one that satisfied narrow chauvinism as well as economic self-interest. The editor of the New York Journal of Medicine put his finger on the situation: "We are at length enabled to procure a better microscope at home, than we are abroad, and at a much more reasonable price."35 As early as 1848 New York City scientists staged something of a microscopical party to show off their instruments, though they adopted the French term, a grande revue de microscope. One of those who attended reported seeing "Dr. Clark with a-we know not whose, Dr. Stout with his Oberheiser [sic], and Professor Gilman with his pet Spencer. There was only wanting Professor Torrey's 'Chevalier' to complete the array. The 'Spencer,' we are proud to say . . . lost nothing by comparison."36 By 1853, with the weight of some six years of encomiums, it was little wonder that the Spencer walked off with the first prize for microscopes at New York's Crystal Palace exhibition.37

33 Burnett, "On Microscopes and Microscopy," pp. 56-63. See also J. Lawrence Smith, "A Comparative Examination of the Objective Glasses of Microscopes from Mr. Ross of England, Mr. Spencer of America, and M. Nachez of Paris," Am. J. Sci., 1851, 2nd Ser. 11:277-278.

34F. Peyre Porcher, letter from Europe, Charleston Medical Journal, 1854, 9:422 (Joseph I. Waring kindly drew this letter to my attention). See also Carpenter, The Microscope, p. 75.

35 Editorial, "American Microscopes," New York J. Med., 1847, 9:401. 36"Microscopy," The Annalist, 1847/1848, 2:34. An informal microscope club apparently existed

in New York City as early as 1840, though the New York Microscopic Society dates only from 1865. The Boston Microscopic Society was established in 1857 as part of the Boston Society of Natural History. Many other microscopic societies sprang up after the Civil War. Some of these are listed in Gage, Microscopy in America, pp. 79-87. Apparently microscopical parties or soirees on a large scale did not join the earlier ether frolics as significant manifestations of the popular culture until after the Civil War. See Schaeffer, "Nineteenth Century American Microscopy," pp. 468-469.

37Benjamin Silliman was among those who acknowledged the preeminence which the Spencer instruments had achieved by then, with their "clearness of definition, power of illumination, absence of color, and breadth of angular aperture" (quoted in editorial, 'Microscopes of American Manufacture," Western Journal of Medicine and Surgery, 1855, 4th Ser., 4:209). In 1851, at London's




Some leading scientists and physicians paid tribute during the 1850s to the genius behind this scientific and technologic breakthrough by making special pilgrimages to the "microscopic Mecca," Canastota. There they admired the master's craftsmanship and methods and left orders for new lenses to meet their own special needs. Prominent among the pilgrims was Holmes, who visited Spencer twice at Canastota, then "a small interior town with the burnt stumps of the forest trees all around it." Looking back upon these visits some years later, he recalled with much relish and some hyperbole how Spencer had "wrought lenses that turned the London makers paler than blue glass would make them look, and with angles of aperture that straddled far outside of the limits which Andrew Ross, the King of them all, declared to be the boundaries of the possible."38 Even Louis Agassiz, who ever since 1831 had been happy with an Oberhauser, finally succumbed to a Spencer in 1857 and sent his assistant, Henry J. Clark, to Canastota to order new and better lenses.39

During this period the demand for microscopes accelerated as hospitals began both to buy their own instruments and to engage microscopic specialists. Some colleges also began to designate trained individuals specifically as instructors or professors of microscopy.40 Meanwhile, to provide guidance in research techniques for the many new users of microscopes, American editions of several standard English microscopy texts appeared during the 1850s, notably those of Beale, Carpenter, and Hassall. Before the decade was over, there were even two wholly American texts, one by Joseph Wythes in 1851 and one by John King in 1859.4' Capitalizing upon the new demand and stimulated by Spencer's success, other American optical firms sprang up during the 1850s.42

Crystal Palace exhibition, J. Lawrence Smith's chemical microscope, as manufactured by C. S. Nachet of Paris, won a gold medal, but through an oversight Smith's name did not appear with the instrument and he did not receive proper credit. J. Lawrence Smith, "The Inverted Microscope," Am. J. Sci., 1852, 2nd Ser., 14:233-234.

38Holmes, "Address to the Boston Microscopical Society," p. 609. 39Henry J. Clark, untitled paper, Proc. Am. Acad. Arts Sci., 1857-1860, 4:136-139. 40Although it was some time before his ideal was approached, William P. Hort of New Orleans

declared in 1850 that "every hospital should be provided with one, or more microscopes of great magnifying power; and especially of powerful defining capacity, so that blood in all diseases could be examined without delay." W. P. Hort, "Remarks on the Distinct and Independent Vitality of the Blood," New Orleans Med. Surg. J., 1850, 7:167. Attending physicians at the Pennsylvania Hospital in 1849 requested the board of managers to purchase a microscope and basic chemical apparatus, while John Bacon, Jr., was appointed chemist-microscopist at the Massachusetts General Hospital in 1850. Moses C. White became Instructor of Microscopy at Yale in 1862. See Whitfield J. Bell, Jr., "Preserving the Archives," Pennsylvania Hospital Bulletin, 1965, 21:5-6, and Long, History of American Pathology, pp. 108, 116, 121.

41Joseph H. Wythes, The Microscopist (Philadelphia: Lindsay & Blakiston, 1851); John King, The Microscopist's Companion (Cincinnati: Rickey, Mallory, 1859). Wythes (sometimes spelled Wythe) was a Methodist minister and religious writer. His Microscopist had four editions by 1880. An American reviewer in 1857 took great relish in exposing an instance in which an English author on the microscope (Jabez Hogg) had apparently plagiarized from Wythes' work in his own text. North American Medical and Chirurgical Review, 1857, 1:571-574.

42These included such firms as J. & W. Grunow of New Haven, Joseph Zentmayer of Philadelphia, Robert B. Tolles of Canastota, and Queen & M'Allister of Philadelphia. For a brief account of these and other early firms, see Oscar W. Richards, "American Microscope Makers and Introduction to the Collection," Journal of the Royal Microscopical Society, 1964, 83:123-126.



88 JAMES H. CASSEDY

By 1860 some of these were marketing extensive lines of microscopes, ranging from inexpensive student models and dissecting instruments to powerful research models. All of them sought endorsements from prominent scientists, though not all succeeded in obtaining statements as effusive as the one that Silliman provided for the Grunow line.43

By the mid-1850s, then, after what was for those times a remarkably rapid process, a consensus had been reached, both that "every man of science has now (or ought to have) a microscope," and that the use of the instrument by medical scientists had already become "general throughout our whole country."44 By extension, it seemed to some a good idea for every citizen to h?ve a microscope, or at least access to one. Now that the instrument was financially within the reach of almost everyone, its use had ceased to be considered a rich man's hobby.45 To some do-gooders, moreover, it had become not only an instrument of the people, but one that could contribute to their uplift. While everyone was certainly not expected to make scientific contributions, everyone could share in the moral benefits which microscopy promised. In Philadelphia, Joseph Wythes noted that "the microscope reveals the most amazing evidence of that creative Power and Wisdom before which great and small are terms without meaning," and he prepared a small book that would instruct children in these religious and scientific interrelationships.46 John King, an eclectic physician from Cincinnati, suggested even broader moral and social possibilities for the instrument:

[The microscope enables a person] to turn to profitable account those hours which might otherwise be passed in ennui, at the drinking saloon, gaming table, or in frivolous or degrading amusements. There is nothing better calculated to improve the world in virtue, morals and science, preserving both sexes alike from temptations and iniquity, and leading all to a correct estimation of the attributes of their Maker, than an early introduction to the wonders and magnificence of nature as disclosed by the powers of a microscope. The head of every family should ponder well upon these few and incontrovertible remarks.47

43Silliman pointed out that the Grunow firm, though in existence only a few years, won the second prize for microscopes at the 1853 Crystal Palace exhibition in New York. "Since that time [they] have steadily advanced in the excellence of all parts of their instruments. Their form of stand for steadiness, ease of management, simplicity and economy, is unrivalled; and the movable stage with universal motion in one plane by one lever, improved and admirably executed by them, is now universally adopted in the best American instruments. Their brass work is perfect in all respects." In optics he thought they were comparable to the Spencer. Silliman, quoted in "Microscopes of American Manufacture," W4est. J. Med. Surg., 1855, 4th Ser., 4:209.

44Unsigned reviews, Southern Med. Surg. J., 1853, N.S. 9:708, and Med. Examiner, 1856, N.S. 12:469. This did not mean that every general practitioner had a microscope. Then, as now, the vast majority of physicians had little time for or interest in research.

45 In 1853 the M'Allister Company of Philadelphia offered a line of cheap compound instruments at prices between $2.50 and $10. Their better compound achromatic microscopes ranged from $16 to $650. See their advertisement in Wythes, Microscopist (2nd ed., 1853). In a parallel situation, the development of inexpensive native-made instruments in the United States during the 1840s and 1850s greatly stimulated the expansion of meteorology and medical climatology.

46Wythes, Microscopist (1851 ed.), p. 13. See also Joseph H. Wythes, The Curiosities of the Microscope, or, Illustratioms of Minute Parts of Creation (Philadelphia: Lindsay & Blakiston, 1852).

47 King, The Microscopist's Companion, p. 49.




We do not really know to what extent ordinary Americans heeded King's suggestion, or how ubiquitous the microscope became in Victorian America.48 But in the medical and scientific parts of that world, at least, the instrument had by 1860 long since ceased to be a rarity. We know that for those medical men who were interested in research-a relatively small segment, as in any age-the microscope not only ushered in a new era of medical inquiry but helped make science itself a newly self-conscious discipline in mid-century United States. Using the new instrument along with the techniques of chemistry and statistical analysis, these investigators began slowly, in the 1850s, to bring a new depth, a new creativity, a new degree of certainty and authority into the American medical sciences. If at first few were completely prepared to undertake sophisticated research projects, a sizable number had the capacity from the beginning to contribute to the advance of research by fashioning certain practical improvements for their microscopes.

Some scientists drew upon their stores of Yankee ingenuity to devise and construct simple attachments. One of them, Holmes, fully as much a chronic tinkerer as he was a compulsive wit and writer, developed improved microscope stands, a portable instrument for classroom use, and an original device to provide good direct lighting.49 Other individuals turned their attention to the design of entirely new types of instruments, at least two of which attracted national and international attention. Riddell in the early 1850s developed a binocular microscope which was the model for most subsequent instruments of that type for over a quarter of a century. Meanwhile, J. Lawrence Smith devised an inverted microscope, known also as a "chemical microscope" for its intended use in that field.50

Another group of American scientists vastly extended the impact of the microscope by adapting it to another product of the new technology, the camera. Through the 1850s some were experimenting with various techniques which would permit accurate reproduction and leisurely study of the objects which they saw in their microscopes. In 1853 Riddell demonstrated to New Orleans medical and scientific groups camera lucida drawings of such objects which he had prepared for viewing through the stereoscope, and Ogden N. Rood carried the process much further at the Rensselaer Polytechnic Institute later in the decade.5' By 1856 John W. Draper had developed his use of the camera obscura to the point where he could illustrate his new text on Human Physiology with many original illustrations created by "microscopic photography." Draper had no doubt that "photography is destined to render important services to

48This should provide another significant area for study. 49Holmes, "Direct Lighting in Microscopic Research," pp. 326-332. Other improvements intro-

duced by Holmes during the 1850s are referred to in Proc. Am. Acad. Arts Sci., 1852-1857, 3:5, 193, 385-386.

50Smith, "The Inverted Microscope," pp. 233-240; John L. Riddell, "On the Binocular Micro- scope," New Orleans Med. Surg. J., 1853/1854, 10:321-327.

51J. L. Riddell, "Match Photographs, or Camera Lucida Drawings of Microscopic Objects for the Stereoscope, made by means of the Ordinary Monocular Microscope," New Orleans Med. Surg. J., 1853/1854, 10:320-321.



90 JAMES H. CASSEDY

science as well as to art."52 Holmes was entranced, less than a half dozen years later, by the "exquisite microscopic photographs" which John Dean of Harvard made of the spinal cord, and particularly of the medulla oblongata.53 By the Civil War these and other Americans had helped advance photomicro- graphy to the point where it was already of practical importance in spreading scientific findings. By the end of the war Joseph J. Woodward was carrying the techniques to a still higher level of quality, one unmatched for some years either in the United States or Europe.54

Despite the innovations in and increasing sales of American-made microscopes during the 1850s, American scientists and medical investigators did not by any means confine themselves to the native instruments.55 As a matter of fact, there was still ample room in the American market for European instruments, and many continued to flow in. For some this was a matter of preference, but in other cases it was one of prestige. To probably an equal degree, it was a natural result of medical or scientific study abroad, for from the 1 840s many American students who learned to use the microscope in Europe purchased the instruments they were familiar with. As Holmes remarked in 1853,

Most of the young physicians who complete their studies in Europe bring home a "Nachet" or an "Oberhaeuser," and a certain skill in handling it. . . . There are now many good instruments among us. . . and several of the highest excellence. Our microscopists are beginning to be known somewhat beyond their own immediate circle.56

Holmes did not mean by this last observation that Americans had already, in a scant dozen years, scaled the heights of biomedical research that European scientists had reached long before. There was still no one on this side of the Atlantic whose work came up to that of K6lliker, Henle, Ehrenberg, or Virchow, to mention only Germans. But, at the same time, the American scientists were not merely artisans tinkering with the practical improvement of their instruments. By the 1850s there were many who could appreciate and even criticize the European works, and some who were undertaking original work. Spearheaded by such investigators, microscopy was steadily finding its way

52John William Draper, Human Physiology, Statical and Dynamical (New York: Harper, 1856), preface, p. iv.

531Oliver Wendell Holmes, "Border Lines of Knowledge in Some Provinces of Medical Science," reprinted in his Medical Essays (new ed., Boston: Houghton, Mifflin, 1889), pp. 241-242. John Dean, Microscopic Anatomy of the Lumbar Enlargement of the Spinal Cord (Cambridge: Welch, Bigelow & Co., 1861).

54Some of Woodward's early photomicrographical work is described in his "On the Use of Aniline in Histological Researches," Am. J. Med. Sci., 1865, N.S. 49:106-113. Secondary accounts of Woodward's work include G. L'E. Turner, "Dr. J. J. Woodward: Microscopist," Proceedings of the Royal Microscopical Society, 1966, 1:33-39.

55 Closely connected with the development of microscopy in anatomical research, of course, was the improvement of techniques for making injections. Various American contributors to these refinements included Goddard, Holmes, Woodward, Horner, Neill, and others. Holmes, in 1853, thought that much of this American work was unexcelled in Europe ("Microscopic Preparations," p. 338).

56 Ibid., p. 337.




into the various medical sciences, particularly in some of the overlapping areas of anatomy, physiology, and pathology.

Microscopic anatomy, or histology, came into its own in this country about this time with American editions of both Hassall's and K6lliker's standard works. However, native American treatises on the subject also began to appear. Among the earliest was the one by the Philadelphian Samuel George Morton.57 Morton, who still found it necessary in 1849 to defend his use of the microscope, pointed out that with it anatomy had become "a new field for discovery, replete with surprising and instructive revelations."58 However, a skeptical reviewer in The Medical Examiner, one who had apparently seen many medical panaceas come and go, was not excited by this latest instrument, and he placed Morton "amongst those who expect too much from microscopic anatomy."59 But Morton was far from alone in mid-century America with his belief in the future of microscopy in anatomy. Indeed, while he regretted that his own early training in the use of the instrument was not adequate for him to make any really original contributions to the field, the new generation of American anatomists included several bright young men who did have the needed skills.60

It was under the guidance of Dr. Paul B. Goddard that Joseph Leidy of Philadelphia started learning microscopic techniques. By the time he was twenty-three Leidy had used the microscope to locate Trichina spiralis larvae in the thigh muscle of a hog and identified them as the same kind of parasite sometimes found in human muscles. Little more than a year later, in 1847, borrowing a high-powered Oberhauser, he carried out his important researches on the structure of the liver.6' Going on to spread himself broadly over a number of sciences, Leidy diluted his potential impact on any of them. But nis use of the microscope set an important example of research excellence for mid-century America. In anatomy alone, his work stood as an effective refutation of outdated critics like Paine, who was still belittling the microscope in the mid-1850s. With the lancet going out of fashion as a standard item in the physician's equipment, Leidy did his best to replace it with the microscope.62

57Arthur Hill Hassall, 7he Microscopic Anatomy of the Human Body in Health and Disease, ed. Henry Vanarsdale, 2 vols. (New York: Pratt, Woodford, 1851); A. Koelliker, Manual of Human Microscopical Anatomy, ed. F. DaCosta (Philadelphia: Lippincott, Grambo, 1854); Samuel George Morton, An Illustrated System of Human Anatomy, Special, General and Microscopic (Philadelphia: Gregg, Elliot & Co., 1849).

58 Morton, Human Anatomy, preface. 59Unsigned review, Med. Examiner, 1849, N.S. 5. 60 Morton commented that he undertook the anatomy text not "as a discoverer, but as a learner;

for although I commenced with the intention of furnishing a series of original drawings, I soon found that it required a more practised eye and hand than mine, to do justice to these delicate manipulations, and that I must be content with the humbler task of occasionally verifying the observations of others." Human Anatomy, preface.

61 Joseph Leidy, "On the Existence of an Entozoon (Trichina Spiralis) in the Superficial Part of the Extensor Muscles of the Thigh of a Hog," Proceedings of the Academy of Natural Sciences (Philadelphia), 1846, 3:107-108; Joseph Leidy, "Researches into the Comparative Structure of the Liver," Am. J. Med. Sci., 1848, N.S. 15.

62 By 1851 a reviewer pointed out that already, for up-to-date anatomists anyway, "the microscope is as familiar as his scalpel." He added that "to teach physiology now, without the assistance of the microscope, is as if one thought to teach anatomy without subjects, or chemistry without apparatus and experiments." C. R. G. [Gilman], review in New York J. Med., 1851, N.S. 7:378.



92 JAMES H. CASSEDY

Through the 1 850s he taught medical students at the University of Pennsylvania that the microscope had become "a necessary companion of every investigating anatomist, physiologist, and pathologist. . . When you compare the extent and exactness of our present knowledge of physiological anatomy . . . with its condition at the commencement of this century, or in the time of Bichat, I think you cannot fail to see and appreciate the great value of the microscope as a means of investigation."63

Like Leidy, Waldo Burnett of Boston found himself in the medical profession in the late 1840s without much of a practice to keep him occupied. And like Leidy, Burnett turned to microscopic research to help fill the empty hours, an example that Holmes recommended enthusiastically to other students.64 Unfortunately, Burnett had only five short years of work left after receiving his M.D. from Harvard in 1849, for he died of tuberculosis in 1854. However, during this time he worked prodigiously both at publicizing the microscope and at using the instrument in his own research, which included investigations in embryology, spermatology, and entomology, but principally in histology. If Burnett's short and hectic microscopic sprint through life failed to produce any strikingly important discoveries, it nevertheless was noteworthy as one of the earliest substantial American involvements with the complex microscopic world of cellular pathology. Confident that the claims for the microscope were irrefutable, he demonstrated its uses in many short studies-such as those on epithelial structures, cheloid growths, and effects of disease on the kidneys- and in one large work, his 1853 prize essay on the cell, a comprehensive review of current European knowledge on the subject which also incorporated his own research.65

In 1849 and 1850 Burnett and some other American observers joined scientists of several European countries in using their new microscopes for a fleeting excursion into the science subsequently known as bacteriology. The return of epidemic cholera provided opportunities for testing the validity of some of the current theories of contagion by attempting, through the microscope, to associate certain organisms with the disease, either as cause or effect. By

63Joseph Leidy, Lecture Introductory to the Course on Anatomy in the University of Pennsylvania, for the Session 1858-59 (Philadelphia: Collins, 1859), pp. 16-17. So far, Leidy's rich career has failed to receive the extensive biographical treatment it deserves. For a short review, see William Shainline Middleton, "Joseph Leidy, Scientist," Annals of Medical History, 1923, 5:100-112; also Dictionary of American Biography.

64 Holmes, "Microscopic Preparations," pp. 337-370. 65Among Burnett's published works, see "Histological Researches on the Development, Nature,

and Function of Epithelial Structures," Am. J. Med. Sci., 1850, N.S. 20:70-82; "The Microscope and Renal Affections . . .," 1851, N.S. 22:373-395; "Observations on the Value of the Microscope as a Means for the Diagnosis of Disease," Southern Medical and Surgical Journal, 1853, N.S. 9:198-206; and "The Cell: Its Physiology, Pathology, and Philosophy, as deduced from Original Investigation, to which is added its History and Criticism," Transactions of the American Medical Association, 1853, 6:647-832. The only substantial discussion of Burnett's work is Jerome Roy Cornfield, "Waldo Irving Burnett, Early American Histologist," Bulletin of the History of Medicine, 1952, 26:430-451; but see also the appreciation by Jeffries Wyman, Boston Med. Surg. J., 1854, 51:41-44. Burnett made it clear, in his paper on the cell (p. 648), that American medical students and researchers should begin paying more attention to the techniques and contributions of German investigators and less to the Parisians.




this time, Americans were becoming aware of Henle's so-called postulates for proving a microorganism origin of disease, and some introduced their own variations. For instance, in 1849 the editor of The Medical Examiner reminded his readers that to successfully link cholera to such an organism, "It must be proved that these [fungous] growths are invariably present in cholera dejections; that they exist in the atmosphere of infected localities; that they are uniform in their character and appearance; and that they are met with under no other circumstances."66

Thus, in an 1849 postmortem examination of a single early victim in Boston, Burnett tentatively identified one of the kinds of animalculae which he saw "swarming and sporting about" as possibly having an association with cholera. However, observations on forty more subjects later in the epidemic revealed this to be only the common Vibrio prolifer of Ehrenberg.67 Somewhat similarly, in St. Louis, R. S. Holmes concluded from microscopic inspection of six patients that the cryptogamic theory of cholera etiology "amounts to nothing."68 But J. T. Plummer of Richmond, Iowa, W. H. Mussey of Cincinatti, and John L. Riddell of New Orleans all thought for a time in 1849 and 1850 that they had seen the causative organism of cholera through their instruments, and Riddell went so far eventually as to give his organism a name, Vibrio biceps. Riddell was also one of some half dozen Americans who, by the mid-1850s, had examined the microscopic constituents of the black vomit of yellow fever. Meanwhile, other investigators were beginning to use the microscope to study the pathology of such chronic diseases as consumption, pneumonia, and cancer.69

Leidy, while not paying any special attention to cholera, went farther into the field of microbiology than any of these other investigators with the possible exception of Riddell. From the mid-1840s Leidy was reporting on new species of minute plants and animals at meetings of the Philadelphia Academy of Natural Sciences. As he displayed the various objects with his microscope, he outlined for the members the unfolding knowledge about the roles of microscopic organisms. There was no room for doubt by 1850 that certain diseases of men and animals-for instance, some skin diseases-were caused by minute parasitic animals or plants; but "that malarial and epidemic fevers

66Editorial in Med. Examiner, 1849, N.S. 5:684. Riddell published a version of the postulates in his "Memoir on the Nature of Miasm and Contagion," p. 368.

67 Waldo . Burnett, "Abstract of a Paper on 'The Microscopical Appearances presented in the Intestinal Discharges and Muscular Fibres of a Patient who died of Epidemic Cholera,"' Am. J. Med. Sci., 1849, N.S. 18:283-284; W. I. Burnett, "Remarks upon the Presence of some Infusoria in the Tissues and Secretions of Patients dying of Cholera," Am. J. Med. Sci., 1850, N.S. 19:261-263.

68Reported in Am. J. Med. Sci., 1850, N.S. 20:263. 691 have commented on the early bacteriological research in "Riddell's Vibrio biceps"; but see

also Riddell, "Notes of Microscopic Observations," pp. 791-794, and John L. Riddell, "Memoir on the Nature of Miasm and Contagion," New Orleans Med. Surg. J., 1859, 16:359-60. Among the more extensive contemporary discussions of the medical applications of microscopy, see Burnett, "The Microscope and the Diagnosis of Disease," pp. 198-206, John H. Packard, "The Present State of Microscopical Science, Medically Considered," North American Medico-Chirurgical Review, 1859, 3:470-492, 658-676, and F. P. Porcher, Illustrations of Disease with the Microscope (Charleston: Evans & Coggswell, 1861). Another Southern scientist who made extensive use of the microscope before the Civil War was Joseph Jones.



94 JAMES H. CASSEDY

have their origin in cryptogamic vegetables or spores requires yet a single proof." To confirm that many of the parasitic animalculae were harmless, Leidy, something like Max von Pettenkofer several decades later, "purposely swallowed large draughts of water containing myriads of Monas, Vibrio, Euglenia, Volvox, Leucaphrys, Paramecium, Vorticelli, etc., without ever having perceived any subsequent effect." And, seeking other possible causes of disease, Leidy examined microscopically the rains and dews in localities along the Schuylkill and Susquehanna rivers where intermittent fevers were epidemic; but he detected no spores or animalculae whatever. Certain that epidemics were not caused by organisms which could not be detected microscopically, he remained skeptical of the germ theory, because he could not see any germs which might be implicated in the local diseases. But he left the matter open pending further research when he summarized his studies in his large 1853 work on Flora and Fauna within Living Animals.70

The failure of mid-century American scientists to prove any connection between microorganisms and cholera and other epidemic diseases, together with the lack of any such proofs coming from Europe, undeniably left the field of etiological opinion to assorted anti-contagionist and miasmatic views. There was no getting around the statistics of successful mortality reduction which were emanating during these decades from environmental sanitation work based upon the filth theory. Public health work based upon such premises, of course, had no need for the microscope; accordingly, health departments mostly remained barren of such instruments throughout the 1850s and for around a quarter of a century after 1860. The expansion of medical microscopy continued during these years, but such work was conspicuously confined to the other branches of medical science.7'

One other enigma which continued to involve some scientists at least partly in microbiology, however, was the question of spontaneous generation. For Leidy, the weight of recent microscopic investigation, including his own, along with limited physical experimentation, made the theory seem most unlikely. The microscope was revealing, he reported, that even the minutest organisms possessed the sexual elements necessary for their own reproduction. True, the modes of the primitive origin of life were unknown. Nevertheless, it seemed logical that life could emerge only from life. "The most prolonged and closest observation," Leidy wrote, "and the most carefully conducted experiments have not led to the proof of a single instance of spontaneous or equivocal generation, even of one of the simplest of all living beings; but, on the contrary, they

70For the development of Leidy's ideas on these subjects, see his remarks in Proc. Acad. Nat. Hist. (Phil.), 1848/1849, 4:225-233, and 1850, 5:7-8. His fullest elaboration was in his Flora and Fauna within Living Animals (Washington, D.C.: Smithsonian Institution, 1853-Smithsonian Contributions to Knowledge, Vol. V).

71 For reasons suggested in this paper, the widespread acceptance of the filth theory of disease between 1850 and 1880 on the part of American physicians and scientists cannot be attributed either to a supposedly low condition of mid-nineteenth-century American science or to a lack of familiarity with and skill in the use of the microscope.




all lead farther and farther from or entirely disprove it."72 Several other American scientist-microscopists of this era followed Leidy closely

in this matter. John C. Dalton of New York flatly rejected spontaneous generation in 1859 with the comment: "The only opinion which is admissable . . . is that organized beings, animal and vegetable, wherever they may be found, are always the progeny of previously existing parents." Similarly, Joseph J. Woodward pointed out that acceptance of Virchow's cellular pathology implied "total denial of the possibility of the spontaneous generation of cells."73

But by no means were all scientists as positive in rejecting spontaneous generation as Woodward, Dalton, and Leidy. Most, in fact, apparently accepted it. And still others remained uncertain because of the apparent contradictions in the evidence. (Pasteur's notable experiments were not published until 1860 and 1861, at the end of the period under study, and evidently had little influence in wartime America.) Jeffries Wyman, for instance, on the basis of original research in the early 1860s, failed to reach any clear-cut conclusions about the phenomenon and felt that his findings could be interpreted differently by different people.74 Again, John Riddell, who had applied chemistry and microscopy for almost two decades in the effort to illuminate such matters, arrived at even more ambiguous findings in 1859. On the one hand, Riddell was satisfied "that vital cells never originate in any other way than as the progeny of pre-existing organisms," and that the organisms of "contagious" diseases are similarly generated. On the other hand, however, there was the problem of the germs or spores of malarial diseases, which seemed to "arise under certain conditions of temperature and season . . . accompanying the decay of vegetable matter"-that is, de novo.75 For Riddell and for most other mid-century scientists, ambiguities like these grew out of and were heightened by their early observations with the microscope. It took another generation or so of research before the ambiguities could be cleared away.

If American scientists of the 1850s and early 1860s did not have the final answers about spontaneous generation, and if they still lacked the microscopic techniques necessary to isolate the causative organisms of cholera and other infectious diseases, they were really little different from most of their European contemporaries. However, they did differ in the size, number, and permanent stability of their research laboratories. While American colleges, natural history societies, medical schools, and other institutions were acquiring their microscopes

72Leidy, Flora and Fauna, pp. 5-14. Leidy himself tested the doctrine of spontaneous generation over a period of about a year and a half between 1850 and 1851 by repeating experiments of the German Franz Schulze. Dalton was also impressed by Schulze's work.

73John C. Dalton, A Treatise on Human Physiology (Philadelphia: Blanchard & Lea, 1859), p. 441; Joseph J. Woodward, review in Am. J. Med. Sci., 1861, N.S. 41:466.

74J. Wyman, "Experiments on the Formation of Infusoria in Boiled Solutions of Organic Matter, Enclosed in Hermetically Sealed Vessels, and Supplied with Pure Air," Am. J. Sci., 1862, 2nd Ser. 34:79-87. For discussion, see Raymond N. Doetsch, "Early American Experiments on 'Spontaneous Generation' by Jeffries Wyman (1814-1894)," J. Hist. Med., 1962, 17:325-332.

75John L. Riddell, "The Chemistry, Physics and Vitality of Organic Cells," New Orleans Med. Surg. J., 1852/1853, 9:462, and Riddell, "Memoir on Miasm and Contagion," esp. p. 368.



96 JAMES H. CASSEDY

along with some chemical apparatus, most of the laboratories remained tiny and fragile operations depending upon the enthusiasm of interested individuals. Lacking the necessary undivided time for research while teaching, trying to build up their laboratory facilities, participating in a variety of civic and scientific activities, such individual Americans could not yet maintain the long-sustained and in-depth microscopic research efforts which were essential to extensive original and important biomedical contributions. Yet, spread out over the various cities, as they developed their instruments, laboratories, and institutions, wrote their texts, translated European works, repeated the European discoveries, and began their own still-modest researches, they were building the necessary foundations of a later more productive American science.

Mid-nineteenth-century American scientists and editors were aware that theirs were exciting times, that they were riding a crest of biomedical progress. If they themselves were not yet contributing very much that was original, they had already become participants in the progress. As they discussed the rapid changes and growth of knowledge which were taking place, some of them debated the causes. Almost everyone agreed that it was mainly a matter of ever more rigorous standards applied to the immensely productive new tools and methodologies. In the case of quantitative facts, the simple amassing of data was starting to give way to newly discriminating and disciplined forms of statistical analysis. In the case of qualitative studies, the assumptions of a priori theory were being discarded in favor of the factual findings of organic chemistry and the microscope. Observers agreed that modern chemistry, with a head start of several decades, had brought the greater benefits in the first fifty years of the century, but by 1860, microscopy had joined chemistry as an essential and complementary part of the evolution in the biomedical sciences. To one observer it even seemed that "for the last ten or twelve years, the microscope has almost thrown the crucible into the shade." To another, it appeared by then that "the science of microscopy [has] a more abundant and profound literature than any other department of human knowledge."776 And Holmes, speaking of the trend he had helped start, concluded:

It would not be surprising to find, in ten years from this time, that there were more microscopists in America than in Europe. For here everybody must know something of everything; and as a microscope is prima facie evidence that the owner is a microscopist, it will become as necessary a part of the stock in trade as a stethoscope.77

There was always the danger, as Holmes pointed out, "that one will play instead

76See Leidy, Introductory Lecture on Anatomy, 1858-1859, p. 16; Burnett, "Microscope and Renal Affections," p. 373; editorial signed L [M. L. Linton?], "The Crucible and the Microscope," St. Louis Medical and Surgical Journal, 1858, 16:196-199; and unsigned review in Southern Med. Surg. J., 1860, N.S. 16:315.

77 Holmes, "Microscopic Preparations," p. 338.




of working with this charming instrument." But that was a temptation which most Victorian Americans, under the sway of the Protestant ethic, apparently managed to resist.78

78 Holmes, "Address to the Boston Microscopical Society," p. 611. While I have seen no estimates of the respective numbers of microscopes in the two parts of the world ten years after Holmes' remarks-i.e., 1863-there is no reason to think that his timetable would have been far off, except for an undoubted slowdown in American scientific and microscopic growth caused by the Civil War. However, the studies necessary to prove this do not exist. In order to illuminate this point as well as to carry forward other inquiries begun in this paper, there should be a detailed examination of the interrelationship of microscopy and science during the Civil War period, as well as that of the subsequent fifteen or twenty years.

Actually, in order to adequately understand American scientific growth during the nineteenth century, studies should be conducted of the impact of the microscope in various sciences. Potentially rich source materials have so far been but little tapped. It is hoped that scholars using them in the future will not limit themselves to delineating the technical development of the instrument. There is an equal need, for instance, for good biographies of the developers, for studies of marketing phenomena affecting the spread of the microscope, for examinations of the instrument's impact upon scientific and medical education, as well as upon the layman's image of science. Finally, there should be studies of what the microscope, as well as the laboratory generally, has done to the American scientist, to his way of life, and to his relations with society and his views of social issues.

