1450

specific. Any primary amine of the aromatic serieswill react with nitrous acid to form a diazo com-

pound, and this in the presence of another basewill yield a more or less coloured azo compound.One of the best combinations of bases for this reactionis sulphanilic acid (which functions as a base)and ot-naphthylamine, suggested by Ilosvay, whichyields a strong pink to crimson colour. The reactionwas at one time held to be too sensitive, but theGriess-Ilosvay reagent is now recognised as the mostsatisfactory for the unfailing detection of nitrous acidin air or water. The syringe described in previousleaflets is used for bubbling known volumes of airthrough the reagent and the number of strokes of thepiston required to produce a standard tint is usedas an inverse measure of the concentration of nitrousacid in the air. The test is simple and should be usedwhenever there is reason to suspect the presenceof nitrous acid in concentrations higher than thosenormally found in air.

First-aid should be rendered by removing theaffected person from the contaminated air and keepinghim warm and at rest in. the prone position. Heshould be given tea or coffee (not alcohol) and onlyremoved to his home or hospital under medical super-vision in an ambulance. Inhalation of oxygen maybe necessary to make up for the haemoglobin whichhas been converted into meth2amoglobin.

QUESTIONS ABOUT HEALTHTHE private practitioner who is inclined, in his

more antibureaucratic moments, to wonder howpublic-health officers fill in their time, may derive acertain savage satisfaction from reading a paper byRobert Oleson,l assistant surgeon-general of theUnited States public-health service. It seems thatbadgering the P.H.S. with questions about healthis a recognised pastime among all classes of Americancitizens. Oleson’s study of 10,000 of these inquiriestends to discredit the view that the female of thespecies is more curious than the male, for abouthalf the communications come from either sex. NewYork, with 1373 questions, is easily the most insatiableof the states, with Pennsylvania (806) and District ofColumbia (532) second and third. Question-timereaches its peak in March and again in October ; but,as might be expected, there is a slump during thesummer when illness is largely forgotten in holidaydistractions. The subjects of inquiry cover an

almost unlimited range ; from the value of chickengizzard in the treatment of cataract to the age ofthe youngest human mother; from the medical useof garlic (20 questions on this) to the name of asolution that will toughen the skin of the hands andso make them less susceptible to cold; from theadvantages of mechanical dish-washing to the con-stitution of fluids suitable for embalming. Nearly800 questions were concerned with the efficacy ofdrugs, nostrums, cosmetics and dentifrices. So far,so good; but included also in this group were

inquiries about remedies prescribed by doctors inattendance on the inquirer, his friends or relations,and such lack of faith is to be deplored. Thoughmost are content to seek information, others areanxious to give it, or rather to sell it. Inventors of

panaceas are willing to part with their secrets forpaltry sums ranging from a hundred thousand to amillion dollars. One correspondent has a scheme forflood-lighting cities with ultraviolet, infrared andcathode rays, thus rendering them germ-free ; anotherwould treat toothache, earache, indigestion, rheu-

1. Oleson, R., Publ. Hlth Rep. Wash. May 12, 1939, p. 765.

matism and (of course) high blood-pressure, to saynothing of " light cases of paralysis," with ten dropson sugar thrice daily of a mixture of gasoline (onegallon !) and pepper (3 drachms), adding, withcharming naivete, that it is " good for almost anydisease." Infantile paralysis evokes a great deal ofamateur attention ; one of the more exciting theoriesof causation put forward is that it is due to over-abundance of sexual energy, and the removal of thesex glands is recommended as a prophylactic, andtherefore presumably routine, measure. Massage withpolecat oil, though less drastic, is little more attractiveas an alternative.

Oleson rightly girds at the lazy student or profes-sional writer who pesters the P.H.S. for data readilyobtainable by library research. He points out thatwhereas the P.H.S. has no wish to shirk its legitimateduty in providing information, enlightenment couldoften as easily, and more rapidly, be obtained nearerhome. Thus local libraries, the family doctor, or thestate department of health, in that order, should firstbe approached.

A NEW TRANSFUSION APPARATUS

THE collection and administration of blood fortransfusion has become so topical a subject that anymodification of technique adopted in other countriesmerits our critical examination. Prof. Hustin andDr. Dumont 1 claim that a modification they haveintroduced has reduced the accidents of transfusionfrom 12 to 3 per cent. in 93 transfusions by lesseningthe chances of clot-formation and of damage tothe blood-platelets. The more effectively clot-formation is eliminated from the apparatus, they say,the less likely is a reaction. In their view the clotdoes not cause a reaction by its embolic action somuch as by the liberation of toxic substances, andthis they support by animal experiment. Certainlyany surgeon whose duty it is to bleed a number ofdonors will agree with them that the commonestsite of clotting is in the actual lumen of the needle.They contend that forceful mixing of the blood andanticoagulant, as with a glass stirring-rod, damagesthe cellular elements of the blood, notably the

platelets. If a suspension of platelets in citratesolution is injected into cats no reaction results, butif the same suspension is first vigorously agitatedin a vessel containing’ beads violent vasomotorreactions may be produced, presumably because thedamaged platelets give rise to some toxin. Theytherefore divide transfusion reactions into two types :first, those due to incompatibility of the blood,where the clinical picture is one of cyanosis, palpitation,flushes, and pain in the loin ; secondly, those due toliberation of toxic substances by blood-clot and

damaged platelets, the clinical picture beingone of rigors, fever, urticarial rashes and oedema.In the latter group there is of course no evidenceof the excretion of haemoglobin and its derivatesin the urine. The apparatus employed closelyresembles that described by Riddell. 2 Suction isprovided by an eccentric cam that compresses a

rubber tube, after the principle of Henry andJouvelet.s A second rubber tube, connected to a

glass tube which dips into the citrate solution, isled direct to the needle, so that it is possible byreversing the direction of the pump to drive thecitrate back from the needle into the vein of thedonor, thus washing the lumen of the needle. The

1. Hustin, A., and Dumont, A., Surg. Gynec. Obstet. May,1939, p. 940.

2. Riddell, V., Brit. med. J. June 3, 1939, p. 1125.3. See Lancet, 1935, 2, 1242.