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of perception； as we know from the delicacy of the sense in blind people。 The statements of the blind concerning their contact sensations may be believed even when they seem improbable； there are blind persons who may feel the very color of fabrics； because the various pigments and their medium give a different surface… quality to the cloth they color。
In another direction； again； it is the deaf who have especial power。 So； we are assured by Abercrombie that in his medical practice he had frequently observed how deaf people will perceive the roll of an approaching wagon； or the approach of a person； long before people with good hearing do so。 For a long time I owned an Angora which； like all Angoras； was completely deaf； and her deafness had been tested by physicians。 Nevertheless； if the animal was dozing somewhere and anybody came near it； she would immediately notice his steps； and would distinguish them； for she would jump up frightened； if the newcomer was unknown； and would stretch herself with pleasure in the expectation of petting if she felt a friend coming。 She would sense the lightest touch on the object she occupied； bench； window…seat； sofa； etc。； and she was especially sensitive to very light scratching of the object。 Such sensitivity is duplicated frequently in persons who are hard of hearing； and whom； therefore； we are likely to doubt。
The sense of touch is； moreover； improved not only by practice； but also by the training of the muscles。 Stricker asserts that he has frequently noticed that the observational capacity of individuals who make much use of their muscles is greater than among persons whose habits are sedentary。 This does not contradict the truth established by many experiments that the educated man is more sensitive in all directions than the uneducated。 Again； women have a better developed sense of touch than men； the space…sense and the pressure…sense being equivalent in both sexes。 On these special forms of the touch…sense injections of various kinds have decided influence。 The injection of morphine； e。 g。； reduces the space…sense in the skin。 _Cannabinum tannicum_ reduces sensibility and alcohol is swift and considerable in its effects。 According to Reichenbach some sensitives are extreme in their feeling。 The best of them notice immediately the approach and relative position of people； or the presence of another in a dark room。 That very nervous people frequently feel air pressure； fine vibrations； etc。； is perfectly true。 And this and other facts show the great variety of touch impressions that may be distinguished。 The sense of temperature has a comparatively high development； and more so in women than in men。 At the lips and with the tips of the fingers； differences of two…tenths of a degree are perceived。 But where an absolute valuation and not a difference is to be perceived； the mean variation； generally； is not much less than 4 degrees。 E。 g。； a temperature of 19 degrees R。 will be estimated at from 17 to 21 degrees。 I believe； however； that the estimation of very common temperatures must be accepted as correct。 E。 g。； anybody accustomed to have his room in winter 14 degrees R。 will immediately notice； and correctly estimate； the rise or fall of one degree。 Again； anybody who takes cold baths in summer will observe a change of one degree in temperature。 It will； therefore； be possible to believe the pronouncements of witnesses concerning a narrow range of temperatures； but all the conditions of perception must be noted for the differences are extreme。 It has been shown； e。 g。； that the whole hand finds water of 29 degrees R。 warmer than water of 32 degrees R。 which is merely tested with the finger。 Further； Weber points out；＇1＇ ‘‘If we put two adjacent fingers into two different warm fluids the sensations flow together in such a way that it is difficult to distinguish differences。 But if we use two hands in this test； it is especially successful when we change the hands from one fluid to another。 The closer the points on the skin which receive contemporary impressions and perhaps； the closer the portions of the brain to which these impressions are sent； the more easily these sensations flow together while again； the further they are from one another the less frequently does this occur。'' In the practice of criminal law such matters will rarely arise； but estimations of temperature are frequently required and their reliability must be established。
＇1＇ E。 H。 Weber： Die Lehre vom Tastsinn u。 Gemeingefhl。 Braunschweig 1851。
It is important to know what a wounded man and his enemy feel in the first instant of the crime and in what degree their testimonies are reliable。 First of all； we have to thank the excellent observations of Weber； for the knowledge that we find it very difficult to discover with closed eyes the angle made by a dagger thrust against the body。 It is equally difficult to determine the direction from which a push or blow has come。 On the other hand we can tell very accurately in what direction a handful of hair is pulled。
With regard to the time it takes to feel contact and pain； it is asserted that a short powerful blow on a corn is felt immediately； but the pain of it one to two seconds later。 It may be that corns have an especial constitution； but otherwise the time assigned before feeling pain is far too long。 Helmholtz made 1850 measurements which proved that the nervous current moves 90 feet a second。 If； then； you prick your finger； you feel it a thirtieth of a second later。 The easiest experiments which may be made in that regard are insufficient to establish anything definite。 We can only say that the perception of a peripheral pain occurs an observable period after the shock； i。 e。； about a third of a second later than its cause。
The sensation of a stab is often identified as contact with a hot object； and it is further asserted that the wounded person feels close to the pain which accompanies the push or the cut； the cold of the blade and its presence in the depths of his body。 So far as I have been able to learn from wounded people； these assertions are not confirmed。 Setting aside individuals who exaggerate intentionally and want to make themselves interesting or to indicate considerable damage； all answers point to the fact that stabs； shots； and blows are sensed as pushes。 In addition； the rising of the blood is felt almost immediately； but nothing else； pain comes much later。 It is asserted by couleur…students＇1＇ who have occasion to have a considerable number of duels behind them； that ‘‘sitting thrusts；'' even when they are made with the sharpest swords； are sensed only as painless； or almost painless； blows or pushes。 Curiously enough all say that the sensation is felt as if caused by some very broad dull tool： a falling shingle； perhaps。 But not one has felt the cold of the entering blade。
＇1＇ Students who are members of student societies distinguished by particular colors。
Soldiers whose shot wounds were inquired into； often just a few minutes after their being wounded； have said unanimously that they had felt only a hard push。
It is quite different with the man who causes the wound。 Lotze has rightly c