196 NATURE AND LIFE. | 
but to effect the composition of albuminous substances, in 
order to give us the complete mastery of the processes which 
Nature follows in her elaboration of immediate principles.- 
That gift of making its object a reality, which is the peculiar 
privilege of chemistry, is also one of the strongest argu- 
ments to bring in proof of the absoluteness of those laws 
which we ascertain respecting the system of forces external 
to us. 
Linnzus, whose mind was remarkably analytical and 
classifying, not only arranged vegetables and animals in 
order, but also classified diseases, and even odors. He 
refers the latter to seven classes: aromatic odors, such 
as that of laurel-leaves; fragrant, like those of lilies and 
jasmine; ambrosial, such as amber, musk, etc.; garlicky, 
like that of garlic; fetid odors, like those of the goat, the 
orage, and others; disgusting odors, as those of many 
plants of the solanez order; and, last of all, nauseous 
odors. The terms of Linnzus have generally become cur- 
rent in language, but we understand, of course, that their 
value is merely conventional. As we have said before, 
there is no standard for the comparison of odors. We can 
only describe them by making comparisons between them, 
according to the degrees of resemblance existing between 
the impressions with which they affect our olfactory mem- 
brane. They have no qualities capable of being rigorous- 
ly defined. This is the reason why it is impossible to give 
them any natural classification. 
Ti. 
The sensations produced by smells are perceived and 
judged of in a great variety of ways, though with less dif- 
ference than prevails as to tastes. “I have seen a man,” 
says Montaigne, “ fly from the smell of apples quicker than 
from a cannonade.” The instance he alludes to in this 
passage is that of Quercet, Francis I.’s secretary, who rose 


