Sect. XXXIX. u. i. GENERATION. 435 



and the various aptitudes to be attracted, which other kinds 

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

 mate matter -, fo the animated fibrils or molecules, which pof- 

 fefs appetencies to embrace, and propenfities to be embraced, 

 which may be called their ethereal properties, coalefce, when 

 they approach each other, and form organized bodies. 



When this organization begins only in a fmgle point, and 

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

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

 pofe an animated being commences ; fuch as the animalcula, 

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

 which have for a time ftagnated ; 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 veficulse feminales, and by the matter of the itch by ftagna- 

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

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

 in fluids recently fecreted. Thefe microfcopic animals confti- 

 tute the primordium vitse, 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 of de- 

 compofing vegetable and animal matters, as well after having 

 been fubjec~ted to the heat of boiling water as before. Thus 

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

 fome boiling hot maihed 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 previouily boiled. Baker on 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 ; 

 and that they afterwards generate others rather more perfect 

 than themfelves by lateral reproduction. From this kind of 

 fpontaneous microfcopic vegetation, I fuppofe the green matter 

 obferved by Dr. Prieftley, 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 Uovvly produced in water in 

 any fituation, and afterwards is propagated with great rapidity •, 

 and according to the obfervations of Senebier it is molt quickly 

 produced in water in which vegetable or animal fubltances are 



in 



