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of almost any kind has been some time in if, animals 

 full of life are produced and so numerous as to equal 

 the fluid itself in quantity. 



A small quantity of water taken from any ditch in 

 summer, is found to abound with just such creatures, 

 only larger. Nay any water, set in open vessels in 

 the'summer months, will after a few days, yield multi- 

 tudes of them. 



These we know by their future changes are the fly- 

 worms of gnats, and several other sorts of flies. And 

 wo easily judge, they owe their origin to the eggs of 

 the parent-fly there deposited. No doubt then but 

 the air abounds with other animalcula, as minute as 

 the worms in these fluids. And these are the flying 

 worms of these animalcula which after a proper time 

 spent in that state, will become flies like those to 

 which they owe their origin. 



The waters in which different liquors are infused 

 afford a proper matter for the worms of different spe- 

 cies of flies. And some of these doubtless are vivipa- 

 rous, others oviparous. This may occasion the ditter- 

 ent time taken up for producing insects in different 

 fluids. Those proper for the worms of a viviparous 

 fly, will be soonest full of them : whereas a longer 

 time is required to hatch the eggs of the oviparous. 

 Now every animalcule being an organized body, 

 how delicate must the parts be that are necessary to 

 make it such, and to preserve its vital actions ? It is 

 hard to conceive, how in so narrow a compass, there 

 is a heart, to be the fountain of life, muscles necessary 

 for its motion, glands to secrete its fluids, stomach and 

 biowels to digest its food, and other innumerable parts, 

 without which an animal cannot subsist. And every 

 one of these must have fibres, membranes, coats, veins, 

 arteries, nerves, and an infinite number of tubes, whose 

 finallncss exceeds all efforts of imagination. And 

 yet there are parts that must be infinitely smaller than 

 these, namely the fluids that move through them, tha 

 blood, lymph and animal spints ? whose subtility, erea 

 in large anhnals ; U incredible. 

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