IMPROVED BY EDUCATION. 173 



ralist. He tied several condors by ropes in a long row at the bottom 

 of a wall; and having folded up a piece of meat in white paper, he 

 walked backwards and forwards carrying it in his hand at the distance 

 of about three yards from them; but no notice whatever was taken of 

 it. He then threw it on the ground within one yard of an old male 

 bird, which looked at it for a moment with attention, but regarded it 

 no more. With a stick he pushed it closer and closer, until at last the 

 bird touched it with its beak : the paper was then instantly torn off 

 with fury, and at the same moment every condor in the long row began 

 struggling, and flapping its wings. "Under the same circumstances, 

 it would have been quite impossible to have deceived a dog." 



As the organ of smell, in all animals that respire air, is situate at 

 the entrance of the organs of respiration, it is probable that its seat, in 

 insects, is in the mouth of the air tubes. This sense appears to guide 

 them to the proper kinds of food, and to the execution of most of the 

 few offices they perform during their transient existence. Occasionally, 

 however, they are deceived by the resemblance between odours of sub- 

 stances very different in other qualities. Certain plants, for example, 

 emit a cadaverous odour similar to putrid flesh, by which the flesh-fly 

 is attracted, and led to deposit its ova in places that can furnish no 

 food to its future progeny. 



As regards the extent of the organ of smell, man is undoubtedly 

 worse situate than most animals ; and all things being, in other respects, 

 equal, it may be fair to presume, that those, in which the olfactory 

 membrane is most extensive, possess the sense of smell most acutely. 

 It is curious, however, that certain animals, which have the sense* of 

 smell in the highest degree, feed on the most fetid substances. The 

 dog, for instance, riots in putridity; and the birds of prey, to which 

 reference has been made, but whose acuteness of smell, we have seen, 

 has been contested, have similar enjoyment. The turkey-buzzard is so 

 fetid and loathsome, that his captors are glad to loosen him from bond- 

 age; and it is affirmed, that if his ordinary foetor be insufficient to 

 produce his release, he affords an irresistible incentive, by ejecting the 

 putrid contents of his stomach upon them I 1 



One inference may, perhaps, be drawn from this penchant of animals 

 with exquisite olfactories for putrid substances ; that the taste of the 

 epicure for game, kept until it has attained the requisite fumet, is not 

 so unnatural as might at first sight appear. 



Like the senses already described, that of smell is to a certain extent 

 under the influence of volition : in other words, it can be exerted 

 actively, and passively. Its active exercise as when we smell any 

 substance to enjoy its sweets, or x test its odorous qualities generally 

 requires prehension, the proper direction of the head towards the object, 

 and more or less contraction of certain muscles of the alse nasi. Doubt- 

 less, here again, the papillae are capable of being erected under atten- 

 tion, as in the senses of taste and touch. On the other hand, we can 

 throw obstacles in the way of the reception of disagreeable odours; 

 and, if necessary, prevent their ingress altogether, by compressing the 

 nostrils with the upper extremity. 



1 Wilson's American Ornithology, by Geo. Ord, Plrilad., 1803-1814. 



