SECT. XXXIX. ii. i. GENERATION. 435 



and the various aptitudes to be attracted, which other kinds 

 poflefs ; which may be termed the ethereal properties of inani- 

 mate matter ; fo the animated fibrils or molecules, which poflefs 

 appetencies to embrace, and propenfnies to be embraced, which 

 may be called their etherial properties, coalefce, when they ap- 

 proach each other, and form organized bodies. 



When this organization begins only in a fingle point, and 

 only enlarges, as it acquires new kinds of appetencies, as ex- 

 plained in the former part of this feftion on Generation, I fup- 

 pofe an animated being commences 5 fuch as the animalcula, 

 which are feen by the folar microfcope in variety of fluids, 

 which have for a time itagnated ; as in infufions of the feeds of 

 plants ; in the femen of animals, and of all other vegetable and 

 animal recrements difFufed in water. Thefe microfcopic ani- 

 mals I fuppofe are produced by the ftagnation of the femen in 

 the veficulae feminales, and by the matter of the itch by ftagna- 

 tion in its puftules, and by the feces by their ftagnation in the 

 inteftines ; but I believe, that they do not exift in the blood, nor 

 in fluids recently fecreted. Thefe microfcopic animals confti- 

 tute the primordium vitss, or firft order of animal life, and prob- 

 ably are not originally propagated, but fimply arife from the dif- 

 folution of all vegetable or animal matter. 



This fpontaneous production of microfcopic animals appears 

 from their being difcovered in a few days in all folutions ofde- 

 compofing vegetable and animal matters, as well after having 

 been fubjeted to the heat of boiling water as before. Thus 

 Mr. Reaumur put fome boiling veal broth, and Mr. Baker put 

 fome boiling hot mafhed potatoes into hot phials, which were 

 clofed with glafs-ftopples ; and both of them in three days be- 

 came as full of animalcula, as the fame materials put into other 

 phials without being previoufly boiled. Bakeron the Microfcope. 



It is probable that there exift microfcopic vegetable produc- 

 tions, as well as microfcopic animals, which may not have been 

 attended to, owing to the quick evaporation of a drop of water 

 in a microfcope ; and that thefe are firft formed fpontaneoufly 

 from the decompofing recrements of vegetable or animal bodies j 

 and that they afterwards generate others rather more per feel: 

 than themfelves by lateral reproduHon. From this kind of 

 fpontaneous microfcopic vegetation, I fuppofe the green matter 

 obferved by Dr. Prieftly, which gives up fo much vital air in 

 the funfhine, originates ; and that it afterwards generates a fuc- 

 ceeding progeny. As it is at firft (lowly produced in water in 

 any fituation, and afterwards is propagated with great rapidity ; 

 and according to the obfervations of Senebier it is mod quickly 

 produced in water in which vegetable or animal fubftances are 



in 



