on the Equivocal Production of Animals. 397 



nion that the infusory animals, ( Fibrio aceti,) found in vinegar 

 and bookbinder's paste, must be of a later creation than the rest of 

 the animal kingdom, because these substances, in which alone they 

 are found, as far as his experience leads him to believe, are artifi- 

 cial inventions of man after he has attained a certain state of civi- 

 lization. But, besides that we are not fully assured that these are 

 the only substances in which these animalcules are found to exist, 

 it may also be observed, that in a state of nature something analo- 

 gous to vinegar may be found in the decomposing processes of many 

 saccharine vegetables, and some substances analogous to paste in 

 the soaked seeds of farinaceous plants. By similar reasoning, we 

 might as well assert the later creation of the Tenebrio moliter, or 

 meal beetle, most generally found in corn artificially ground into 

 meal or flour, or the Acarus domesticus, or cheese mite, a regular 

 inhabitant of the artificial products of the dairy. 



The manner of conception and propagation, as seen in all its 

 various forms, in the different classes of animals, is still to us an 

 impenetrable mystery, much more so the original process by which, 

 from inert matter, sprung life and organization. Some philoso- 

 phers have eagerly grasped at the idea of the spontaneous forma- 

 tion of animalcules ; and, supposing a gradual and progressive ex- 

 tension of organization from these up to the most perfect and com- 

 plicated animals, have thus endeavoured to account for all the phe- 

 nomena of life. But, besides that all such progressive changes is 

 directly contradicted by the actual state of animal existence, even 

 this primitive formation with which they set out, is a mystery to- 

 tally inexplicable. Mere matter of itself, is inert, and incapable of 

 assuming organization and life. Some vivifying principle must 

 have been added. Some First Cause must have given a determi- 

 nate form, and prescribed to such creations regular and definite 

 limits. * 



ART. II. A71 easy mode of washing Precipitates, orjiltering large 

 quantities of Liquid. By James F. W. Johnston, A.M. 



One of the most tedious, and yet to the analytical chemist most 

 frequent and most necessary operations, is the washing of precipi- 

 tates on the filter. The irksomeness consists in its being necessary 

 constantly to watch over the process, so as to keep the precipitate 

 covered with water ; and it is rendered tedious, and often imper- 

 fect, by the impossibility of continuing the operation during the 

 night. By standing over night, the precipitate dries and consoli- 



" The arguments for the other side of the question of spontaneous generation, 

 are fairly stated in an article by Dr. Scouler in a recent number of the Glasgow 

 Medical and Surgical Journal. Ed. 



