INTRODUCTION 
Kt 
and thus by yielding to, and humouring the motion 
<of tHe limbs and twigs, or other fupport on which 
they depend, are not fo liable to be torn off by fud- 
den blafts of wind or other affauks : is it fenfe or 
inftinct that influences their actions ? it mud be 
fome impuife ; or does the hand of the Almighty 
act and perform this work in our fight ? 
The vital principle or efficient caufe of motion 
and action, in the animal and vegetable * fyftem, 
perhaps, may be more fimilar than we generally ap- 
prehend. Where is the eifential difference between 
the feed of peas, peaches, and other tribes of plants 
and trees, and the eggs of oviparous animals, as of 
birds, makes, or butterflies, fpawn of &lh, &c. ? 
Let us begin at the fource of terreflrial exiltence. 
Are not the feeds of vegetables, and the eggs of 
oviparous animals fecundated^ or influenced with 
the vivific principle of life, through the approxima- 
tion and intimacy of the fexes ? and immediately 
after the eggs and feeds are hatched, does not the 
young larva and infant plant, by heat and' moifture, 
rife into exigence, increafe, and in due time arrive 
to a (late of perfect, maturity ? The phyfioiogifts 
agree in opinion, that the work of generation in vi- 
viparous animals, is exactly fimilar, only more fe- 
cret and enveloped. The mode of operation that 
nature purfues in the production of vegetables, and 
oviparous animals, is infinitely more uniform and 
nranifeft, than that which is or can be difcovered to 
take place in viviparous animals. 
The moil apparent difference between animals 
and vegetables is, that animals have the powers of 
found, and are locomotive, whereas vegetables are 
not able to fhift themfelves from the places where 
nature has planted them : yet vegetables have the 
yowe* of moving and exercifing their members, and 
* yid. Sponfaiia plantarum, Amoen. Acadl. n. 12. Linn. 
have 
