Jlnimal Excnments. 315 
ANIMAL EXCREMENTS CONSIDERED AS xMANURE, 
[From the Journal of Agriculture.] 
It is always a pleasure to read a book when the author is in 
earnest on his subject — the importance of which the question bears 
in his own estimation is sure to be communicated to his readers. 
It is in opposition to the most settled opinion of human nature to 
expect that we can interest others in that in which we are not 
interested ourselves. There can be little doubt but that it is to 
the earnestness with which they have treated their subject, that 
the honored names of Liebig, Boussingault, Johnston and others 
are indebted for their present position. Though the author of the 
interesting work now before us, has only treated on one subject 
connected with scientific agriculture, yet he has done so in such a 
clear, lucid manner as to merit our attention. 
M. Gerardin, in his introductory address, states that his greatest 
wish is to show, not the theory, hut the 'practice best adapted to 
general use. His text is — 
" The base of agriculture is manures; and of all manures, ani- 
mal excrements are the best adapted to our varied soils and crops. 
Observation of the plainest facts must have shown you that good 
crops are insured by the abundant application of manures. But 
to manure well, you must have plenty of manures; and if you are 
unable to do the ibrmer, it is because you neglect ihe means within 
your reach of improving the quality and increasing the quantity 
of your farm-yard manures. Your own interest requires the imme- 
diate removal of this evil." 
It is well known that the nature and properties of manures de- 
pend on, 1st, the species of animal from which they are derived ; 
2d, on the food given to them; 3d, on the substances with which 
they are littered; and, 4th, especially upon the care bestowed 
upon their management. 
\st. On the relative value of the different Manures derived from 
various Animals. 
From Birds. — The attention of the whole civilized w^orld has 
been for the last few years directed to the desert shores of Africa 
and Peru, whence, between 1841 and 1844, England imported 
not less than 70,000 tons of the excrements of birds. This guano, 
or huano, (as it is called by the natives,) has undoubtedly proved 
of great utility to English agriculture; but its value has been 
very much diminished by the unscrupulous manner in which it 
was adulterated, rendering it impossible for any one but a scientific 
chemist to judge of its worth. Nothing can be more fallaciou 
