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Queen’s or King’s Prize. Two of these, incidentally, hadan amblyopic eye.

Before 1909 or 1910 the full range shot had to focusthree objects more or less simultaneously-i.e., mark,foresight, and backsight. When the hindsight usedwas a bar, as against a notch, white lines, to allowfor wind deflection, were drawn on it, and the focusingof these presented a good deal of difficulty to thehypermetrope. Nowadays, with the peep sight, usingan aperture of anything from 0-03 to 0-08 inch indiameter, only two objects have to be picked up-i.e.,the mark and the foresight. As the foresight is about32 inches distant from the eye, both points cannot bein perfect focus at the same moment and it is thealmost universal habit of rifle shots to concentrate, atthe instant of pressing the trigger, on the foresight,trusting to the hold to keep true to the point of aimon the target.

I have called the point of aim the mark, but actuallythis is a very variable item, differing in many ways indifferent men. Some aim into the aiming mark, somejust below, some well below. Others " sense " thecentral point using, they say, the four corners asradii. Others again take the central point of the topor bottom edge of the target as the point of alignment.It is impossible to decide between the respectiveadvantages of all these as their various upholders areall equally good shots. Whatever the distant marktaken the near one is always, in all cases, the tip ofthe foresight centred in the middle of the peep andI have found that, in the hypermetropic presbyopethat it is frequently difficult to define it with theclarity desired. The sharpness can be obtained innearly every case by cutting down the size of theaperture ; but this is very undesirable, for there canbe no question that, within limits, the apertureshould admit of as much light as possible passingthrough it. Therefore, in the presbyopic hyperme-trope an addition to his distance vision correction iscalled for and + 0-5 or even z 0-75 will give a squarecut, sharply defined tip of the foresight, though atthe expense of some blurring of the target. Thisblurring takes a little while to get accustomed to, andsome people, particularly those with very slighthypermetropia, never settle down to it. In brightlights, where a medium aperture can be used, it wouldnot seem so useful as in dull ones where a large oneis needed.

Theoretically, the myopic presbyope might use theadditional correction but I have no data on this sideof the question, and the loss of definition of the

target, is, I think, more serious to the myope than tothe hypermetrope.As I pointed out in my paper, it is not so much the

question of improved visual acuity, important as thisis, that one hopes to obtain by prescription of glasses,but the relief of fatigue. Most men, if they can seefairly well, can fire a few shots without feeling muchstrain, but when it comes to 7, 10, 15, or 20 con-secutive ones there is an intense strain, not only onthe eye but on the nervous and muscular systemgenerally, and the oculist’s purpose is to relieve theocular part of this as much as possible--i.e., to putthe eye under the best conditions to carry on for along period without having to undergo unnecessarystrain.

Glare, too, has to be considered, and the use oftinted glasses will help in modifying this. Each manhas his own taste in the matter. I find that CrookesA or B are quite satisfactory in England, but somemen prefer amber, Fieuzal, green or other glasses.Possibly the darker shades might be objected to onthe ground that the pupil might tend to dilate and so

lose the advantage of a diminished cone of rays ; butthis would be too infinitesimal to be a serious objection.No matter how acute the vision is, or is made to

be by glasses, it must never be forgotten that thevision is only one of the many components of goodshooting and that though it is very important, thekeenest eyesight does not complete the make-up ofthe good shot.

I am, Sir, yours faithfully, --

Cannon-street, E.C. C. WYNN WIRGMAN.

RUPTURE OF THE CÆCUM

To the Editor of THE LANCET

SiB,—In THE LANCET of Oct. 13th, 1934 (p. 810),Dr. W. N. P. Wakeley described a case of perforationof the caecum due to annular carcinoma of the sig-moid flexure of the colon. In Vienna in 1932 Isaw several cases of this type. The explanationgiven was that the primary dilatation occurs justproximal to the obstruction, but that secondaryhypertrophy in this region of the wall follows. Asthe lesion progresses there is a more rapid dilatationof the ascending colon, due to the effect of the lesionand aided by the hypertrophy of the descendingcolon acting against the caecum and the ileocaecalvalve. The combined effect is to cause rupture ofsome part of the ascending colon, usually at or nearthe caecum, and always in the longitudinal band.

I am, Sir, yours faithfully,Philadelphia, Dec. 22nd, 1934. WM. STEINBERG, M.D.

HUGHLINGS JACKSON AND THESUBCONSCIOUS MIND

To the Editor of THE LANCET

SiB,—In his Schorstein lecture (THE LANCET,Oct. 27th, 1934) Sir E. Farquhar Buzzard entertainsus with personal reminiscences of Dr. HughlingsJackson and his influence on neurology. He quotessomething that Jackson wrote " nearly 50 yearsago," adding " before the subconscious mind ’ hadbeen invented ! " This is surely a slip. Uncon-scious mental action had been recognised and writtenabout many years before this. To the best of myknowledge, Dr. W. B. Carpenter was the first to

speak of it definitely and distinctly. He introducesa lecture delivered at Manchester in December,1871, on " The Unconscious Action of the Brain "by telling his audience that he is about to describeprocesses at the depth of the mind. He had lecturedon the same subject at the Royal Institution fiveyears before, and deals at length with " unconsciouscerebration " in his book on Mental Physiology,1874. I think that he does not often get the creditthat is due to him. Dr. Charlton Bastian alsowrote of unconscious mental processes, saying thatmind was more extensive than consciousness, and inhis " Brain as an Organ of Mind," he refers toothers who supported him, including Bain and

Spencer. Occasional examples of unconscious mentalaction had often been recorded as curiosities, butwere not systematically described and understooduntil physiology advanced and joined forces, andDr. Carpenter became its chief prophet.

I am, Sir, yours faithfully,F. LUCAS BENHAM, M.D., M.R.C.P.

Semaphore, South Australia, Dec. 5th, 1934.

ST. JOSEPH’S HOSPITAL, PRESTON.-Lord Stanleyhas opened a new wing at this hospital which is to be

mainly used for maternity cases.