the premises and declared with evident 

 honest)' that he could detect nothing 

 disagreeable in the air nor any sort of 

 a scent that did not properly belong to 

 a rendering establishment. Those who 

 v^ork where theie are strong and dis- 

 agreeable odors soon become so accus- 

 tomed to peculiar smells that they do 

 not notice them at all, although they 

 are keen to detect any unusual odor, 

 as when the liquor in a tanner's vat has 

 not in it the proper admixture of ma- 

 terials. 



All the lower animals seem to be 

 positive as to the direction of the 

 source of any scent, but man is power- 

 less in the matter. He merely knows 

 an odor is present, but is unable to tell 

 without moving about whether it comes 

 from one side of him or another. A 

 blindfolded bo}' cannot tell which side 

 of his nose is nearest to a suspended 

 orange. 



To affect this sense a substance must 

 be dissolved or scattered through the 

 atmosphere to be breathed. Whether 

 such substances are divided and used 

 up in giving out odors is still a ques- 

 tion. Some of them, as the essential 

 oils, waste away when exposed to the 

 air, but a grain of musk remains a grain 

 of musk with undiminished power after 

 years of exposure. The experiment is 

 such a delicate one in connection with 

 the musk that it has never been settled 

 to the satisfaction of science. 



Substances which scatter themselves 

 readily through the air are usually 

 odorous, while those which do not are 

 generally without smell. But many of 

 these when transformed into vapors, as 

 by the application of heat, become 

 strongly odorous. Bodies existing 

 naturally in the gaseous state are usu- 

 ally the most penetrating and effective 

 as odors. Sulphuretted and carburetted 

 hydrogen are examples of these. 



College boys sometimes procure 

 from the chemical laboratories of their 

 institutions materials which are used 

 with telling effect on the social func- 

 tions of higher or lower classes; in one 

 instance a banquet was cleared of guests 

 by the conscienceless introduction of 

 chemicals just before the festivities 

 were to have begun. Efforts to intro- 

 duce powerful gases as weapons in war 



have failed because the effect is not 

 confined to the enemy. 



Gases which are offensive are not 

 always positively harmful, but as a rule 

 those which offend the nose are to be 

 avoided. Some deadly gases do not 

 affect the sense of smell at all, as in the 

 case of earth damp which stupefies and 

 kills men in mines and wells without 

 warning. But the nose is a great de- 

 tector of bad air, especially that of a 

 noxious character, and sewer gas as 

 well as other poisonous airs which 

 bring on the worst types of fever are 

 offensive to one who is not living all 

 the time within their range. 



But a small part of the mucous 

 membrane of the nose is the seat of this 

 important sense. The olfactory cells 

 are not as easily examined and traced 

 in their connections as are the end or- 

 gans of the sense of taste. Yet the 

 anatomist finds in the structure of the 

 noses of the flesh-eating animals suffi- 

 cient indications of their superiority 

 over man in the exercise of the sense 

 of smell. The peculiar development 

 of the membrane and the complicated 

 structure of the nasal cavities in the re- 

 gion occupied by the cells which are 

 supposed to connect with the extreme 

 divisions of the olfactory nerve are all 

 that one would expect from the differ- 

 ences in endowment. 



Aside from peculiar powers of smell 

 there are other endowments of noses 

 which are remarkable. The common 

 hog has a snout that is easily moved 

 and has great strength. He can take 

 down a rail fence with it quite as skill- 

 fully as a boy would do it. He can 

 turn a furrow in the soil in search of 

 eatable roots, and when the ground is 

 frozen to a considerable degree of hard- 

 ness he pursues his occupation with un- 

 abated zeal and no evident embarrass- 

 ment. 



The fresh-water sturgeon has a large 

 gristle in his nose which boys some- 

 times convert into a substitute for a 

 rubber ball. His nose is a useful in- 

 strument in securing food from the 

 mud in the river bottom. The rhinoc- 

 eros has a fierce horny protuberance 

 rising from his nose which is valuable 

 to him in war. Indeed some are 

 equipped with two horns, one behind 



