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sans action, sans mouvement; et l’on peut conjecturer qu’il existe un equili- 
bre parfait entre 1 action et la reaction des diverses parties qui la composent. 
Alors la plantule on l’embryon vegetal, qni constitue la partie essentielle de 
cette semence, ne peut etre considere ni comme jouissant de la vie , car elle 
n’existe point sans mouvement organique, ni comme en etant totalement de - 
pourvue ; car ce qui la constitue peut etre suspendu, et il lest effectivement 
avant la germination si toutefois il existe. La vie alors n’attend qu’un sti¬ 
mulus particulier, et qu’un premier mouvement communique aux tendres 
organes de la plantule, pour jouir d’une existence active, et commencer a 
operer les developpemens qui resultent de son action.” * 
John Hunter was the first, I believe, who proved the vitality of Eggs. 
I had long supposed, says this illustrious Physiologist, that the principle of 
life was not wholly confined to animals, or animal substance endowed with 
visible organization and spontaneous motion ; but believed that the same 
principle might exist in animal substances, devoid of apparent organization 
and motion. 
I was led to this opinion about twenty years ago, when busied in making 
observations on the growth of the chick in the process of incubation. I then 
observed, that whenever an egg was hatched, the yolk (which is not dimi¬ 
nished in the time of incubation) was always perfectly sweet to the very 
last; and that the part of the albumen, which has not been expended on the 
growth of the animal, some days before hatching, was also perfectly sweet, 
although both were kept in a heat of 103° in the hen’s egg for three weeks, 
and in the duck’s for four; and I observed, that if an egg was not hatched, 
that egg became putrid in nearly the same time with any other dead animal 
substance. To determine how far eggs were possessed of a living principle I 
made the following experiments. 
* Until the period of germination, all the parts of a seed which are separate from the mother 
plant, are in a sort of complete repose; the contained fluids are in moderate quantity, without action, 
or movement; and we may suppose, that the equilibrium betwixt action and reaction of the different 
component parts is equal. Then the plantule, or essence of the seed, cannot be said to possess life, 
for this depends upon organic movement; nor can it be said to be altogether deprived of life, for this 
principle may be suspended, and is altogether so, before germination, if indeed in that state it can 
be allowed to exist. Life then would depend upon a proper stimulus, and this producing the first 
movements to the tender organs of the plantule, endows it afterwards with active existence, and 
the future developement which ensues. 
