464 Obsermtions on Animalcules. 
small,can live upon water alone ; but wlien it is stored with proper 
food, the microscope will exhibit to the admiring eye myriads of living 
creatures in every drop. New made hay, cut into small lengths, and 
put into water, will in a few days, produce a whitish scum on the 
surface, which, when examined by the microscope, will be found to 
contain inexpressible numbers of animalcules. The most general 
among tliem is an oval sort, somewhat in the shape of an ant's egg; 
these are extremely nimble, and in a continual swift motion backwards 
and forwards : but sometimes they stop on a sudden, and turn round 
on their OAvn axis many times, with surprising velocity, first one way, 
and afterwards the contrary. Another sort, common to this infusion, 
is clear and transparent, but curiously ribbed, in the manner of a 
melon. Others are transparent at their extremity only, and in these 
neither legs nor fins are discernable. 
Vinegar, after standing a few days uncovered, especially in the 
summer season, will abound with animalcules in the shape of eels. 
It is common in summer for the water that stands in ditches, to 
appear sometimes of a greenish, and at other times of a reddish 
colour. This on examination with the microscope, has been found to 
be entirely owing to the millions of animalcules crowded together on 
the surface. 
" Where the pool 
"Stands mantled o'er with green, invisible 
"Amid the floating verdure, millions stray." 
"Nor is the stream 
"Of purest crystal, nor the lucid air, 
"Though one transparent vacancy it seem, 
"Void of their unseen people." 
Leewenhoeck calculates, that a thousand millions of animalcules 
observed in common water, are not altogether so large as a grain of 
sand! Eminent naturalists have discovered not less than 30,000 in 
a single drop ! Every animalcule being an organized body, how 
delicate and subtle must be the parts necessary to constitute it, and 
preserve its \atal actions ! How inconceivably small, and yet a per- 
fect animal! In animalcules we discover the same muliiplication of 
parts, diversity of figures, and variety of motions, as in the largest 
animals. How amazingly curious must be the internal structure of 
these little creatures, — how minute the bones, joints, muscles, ten- 
dons, — how exquisitely delicate the veins, arteries, nerves, — ^what a 
number of vessels and different circulations must be contained in one 
of them! It is difficult to conceive how, in so narrow a compass, 
there should be contained a heart, as the fountain of life, propelling 
the circulating fluid, — veins and arteries, a« the conductors of the 
