VITALI PRINCIPLE. 29 
2. Moisture. — After the germ has been produced by the 
vital force of the parent, a determinate quantity of mois- 
ture appears to be necessary to enable it to exercise the 
functions of an independent being. In the case of the seeds 
of plants, and the eggs of all the aquatic animals, the vital 
spark, though existing, is unable to display its energies 
when placed beyond the influence of water. Even after 
the germs have expanded into maturity, the abstraction of 
moisture frequently produces a cessation of every func- 
tion. This assertion may be verified, by placing a snail in 
adry situation during the summer. Animation becomes sus- 
pended, and will continue so for several years, but will re- 
turn upon moistening the shell with water. Similar effects 
may be observed with many of the infusory animalcules. 
These facts have given rise to the opinion which very ge- 
nerally prevails, that the vital principle resides in the solids, 
as solids, and that, by means of moisture, it exerts its in- 
fluence on inorganic matter. Others, on the contrary, 
considering that the fluids furnish the materials for the 
construction of the different organs, and are indispensably 
necessary in the various processes of absorption, secretion, 
and every other function, consider that the vital principle 
resides in the fluids) Harvey and Hunter assert, that 
both the blood and the chyle have life; while ALsrnus is 
disposed to grant it even to the excrement. It is, however, 
probable, that the living principle resides both in the solids 
and fluids, as we can form no conception of an organized 
body that does not consist of vessels and contained fluids ; 
neither have we an idea of life that does not include the 
motion of these fluids. The vital principle may be retain- 
ed, though inactive, even after a considerable part of the 
fluid has been extracted ; and, in the case of the snails 
and animalcules, revive upon the addition of water. But 
thereis not a single experiment which countenances the idea 
