IN ANIMALS. 143 



to him, when he has thoroughly examined it by the touch. Baczko, 

 referred to by Rudolphi, 1 who describes his own case, could discriminate 

 between samples of woollen cloth of equal quality but of different 

 colours. The black appeared to him among the roughest and hardest : 

 to this succeeded dark blue and dark brown, which he could not, how- 

 ever, distinguish from each other. The colours of cotton and silk stuffs 

 he was unable to discriminate ; and he properly enough doubts the case 

 of a Count Lynar, blind, who, it was said, was capable of judging of 

 the colour of a horse by the feel. The only means the blind can possess 

 of discriminating colours must be through the physical differences of 

 surface, which render it capable of reflecting one ray or combination 

 of rays, whilst it absorbs the rest ; and if these differences were insuf- 

 ficient to enable Baczko to detect the differences between cotton and 

 silk fabrics, it is not probable, that the sleek surface of the horse would 

 admit of such discrimination. 



In animals the organ of touch varies. The monkey's resembles that 

 of man. In other quadrupeds, it is seated in the lips, snout, or pro- 

 boscis. In molluscous animals, the tentacula; and in insects, the antennae 

 or feelers, are organs of touch, possessing, in some, very great sensi- 

 bility. Bats appear to have this to an unusual degree. Spallanzani 

 observed them, even after their eyes had been destroyed and the ears 

 and nostrils closed, flying through intricate passages, without striking 

 the walls, and dexterously avoiding cords and lines placed in the way. 

 The membrane of the wings is, in the opinion of Cuvier and many 

 others, 2 the organ that receives an impression produced by a change in 

 the resistance of the air. M. Jurine concludes, that neither hearing 

 nor smell is the channel through which they obtain perception of 

 the presence and situation of surrounding bodies. He ascribes this 

 extraordinary faculty to the great sensibility of the skin of the upper 

 jaw, mouth, and external ear, which are furnished with large nerves ; 

 whilst Sir Anthony Carlisle attributes it to the extreme delicacy of 

 hearing possessed by the animal ; 3 a view which is confirmed by ex- 

 periments instituted by the author's friend, Professor J. K. Mitchell, 

 of Philadelphia. Certain experiments by Mr. Broughton, 4 sanction 

 the idea that this may be, in part, dependent upon their whiskers. 

 These, which are found on the upper lip of feline and other animals, 

 are plentifully supplied with nerves, which seem to proceed from the 

 second branch of the fifth pair, and are lost in the substance of the 

 hairs. In an experiment, made by Mr. Broughton on a kitten, he found 

 that whilst the whiskers were entire, it was capable of threading its 

 way, blindfold, from a labyrinth in which it was designedly placed ; but 

 it was totally unable to do so when the whiskers were cut off. It struck 

 its head repeatedly against the sides ; ran against all the corners ; and 

 tumbled over steps placed in the way, instead of avoiding them, as it 

 did prior to the removal of the whiskers. 



From facts like these Mr. Broughton drew the conclusion, that cer- 



1 Grundriss der Physiologie, 2er Band, s. 85, Berlin, 1823. 



2 Carpenter, Human Physiology, p. 253, Lond., 1842. 



a See Roget's Animal and Vegetable Physiology, ii. 399, Amer. edit., Philad., 1836. 

 London Medical and Physical Journal, for 1823. 



