46 INTRODUCTION. 



cular turn; and in the Ornithorhynchus, in which the osseous orifice of 

 the internal ear opens with a basal, or downward aspect, and is, moreover, 

 very minute, the cartilaginous canal winds round the temporal bone, and 

 its earless external orifice is capable of being contracted or dilated at 

 pleasure. The Hippopotamus possesses the power of closing the exter- 

 nal orifice of the meatus auditorius by means of a muscular apparatus, in 

 order to exclude the entrance of water while below its surface ; and the 

 Water-shrew, the Mole, and other diving and burrowing animals, have 

 the same power. In Man, and other Mammalia, the wax, as it is termed, 

 secreted by small glands on the lining membrane of the meatus auditorius, 

 is evidently intended to prevent the intrusion of insects, and to restrain 

 particles of dust from farther ingress. 



With regard to the perfection in which the sense of hearing is en- 

 joyed by Mammalia, there appears to be a great range of variation. 

 Many are capable of hearing sounds at a distance far beyond the limits 

 of the human senses ; while others are familiar with tones, which, though 

 produced close at hand, are either scarcely, or not at all, appreciable by 

 the human organs. It would appear, from many circumstances, that 

 animals derive pleasure from musical sounds, and are diversly affected 

 by various tones, or notes, produced within their hearing : to ascertain 

 the extent of the influence of such a cause, is almost impossible ; but 

 in Man alone " the concord of sweet sounds," acting like a charm upon 

 the imagination, produces delight, and ever-changing emotions.* 



* It is interesting to know how severe and constant practice, under the discipline of necessity, 

 sharpens the senses in the human being : not, indeed, to the degree in which they are possessed by the 

 brute, which depends solely upon them for the acquisition of food and the avoiding of danger ; but to an 

 extent surprising to the natives of civilized countries, where such a mode of exercising them is never 

 needed. We all know how practice improves the ear in the discrimination of musical notes, and from 

 this may judge what it will do for the other senses. 



The Calmucks, says Pallas, who, in his frequent intercourse with the Nomadic tribes of Asia, had 

 most excellent opportunities of observing the powers of their external senses, " have a fine nose, a good 

 ear, and an extremely acute eye. On their journeys and military expeditions they often smell out a fire, 

 or a camp, and thus procure quarters for the night, or obtain booty. Many of them can tell, by smelling 

 at the hole of a fox, or other animal, whether the creature be there or not. By lying flat, and putting 

 their ear to the ground, they can catch, at a great distance, the noise of horses, of a flock, or of a single 

 strayed animal. But nothing is so surprising as the perfection of their eyes, and the extraordinary dis- 

 tance at which they often perceive, from inconsiderable heights, small objects, such as the rising dust 

 caused by cattle or horsemen ; more especially as the undulation of the boundless steppes, or plains, and 

 the vapours which rise from and float upon them, in warm weather, render things very obscure. In the 

 expedition which the Torgot Vice-Chan Ubaschi led against the Kubanians, the Calmuck force would 

 certainly have missed the enemy, if a common Calmuck had not perceived, at the estimated distance of 

 thirty versts, the smoke and dust of the hostile army, and pointed it out to other equally experienced 

 eyes ; when the commander, Colonel Kischmskoi, could discern nothing with a good glass. They pur- 

 sue lost or stolen cattle, by the track, for miles over deserts. Kirgises, or even Russians, in the wild 

 parts of the empire, are equally able to follow and discriminate tracks by the eye. This, indeed, is not 

 difficult on soft ground, or over snow ; but it requires great practice and skill to choose the right, out of 

 several intermingled traces, to follow it over loose sand or snow, not to lose it in marshes or deep grass, 

 but rather to judge, from the direction of the grass, or from the depth of the print, in snow or sand, how 

 long it has been made." PALLAS, Samm. Hist. Nach. Th. 1. pp. 100, 101. 



The Hottentots, according to Barrow, " by the quickness of their eye, will discover Deer, and other 

 sorts of game, when very far distant ; and they are equally expert in watching a Bee to its nest. They 



