SPONTANEOUS GENERATION-: A LAST WORD. 



509 



of them bore the ordeal. These results were 

 clearly foreseen before they were realized, so that 

 the germ-theory fulfills the test of every true 

 theory, that test being the power of prevision. 



When my respondent speaks of "naked or 

 almost naked specks of protoplasm," he draws, as 

 I have intimated, upon his own imagination, not 

 upon the objective truth of Nature. His words 

 seem the words of knowledge, but his knowledge 

 is really nil. He concedes the possibility of a 

 "thin covering." Such a covering may, how- 

 ever, exercise a powerful protective influence. A 

 thin pellicle of India-rubber, for example, sur- 

 rounding a pea, keeps it hard in boiling water for 

 a time sufficient to reduce an uncovered pea to a 

 pulp. The pellicle prevents imbibition, diffusion, 

 and the consequent disintegration. A greasy or 

 oily surface, or even the layer of air which clings 

 to certain bodies, would act to some extent in a 

 similar way. " The singular resistance of green 

 vegetables to sterilization," says Dr. William 

 Roberts, " appears to be due to some peculiarity 

 of the surface, perhaps their smooth, glistening 

 epidermis which prevented complete wetting of 

 their surfaces." I pointed out in 1876 that the 

 process by which an atmospheric germ is wetted 

 would be an interesting subject of investigation. 

 A dry microscope covering-glass may be caused 

 to float on water for a year. A sewing-needle 

 may be similarly kept floating, though its specific 

 gravity is nearly eight times that of water. Were 

 it not for some specific relation between the mat- 

 ter of the germ and that of the liquid into which 

 it falls, wetting would be simply impossible. An- 

 tecedent to all development there must be an in- 

 terchange of matter between the germ and its 

 environment ; and this interchange must obvious- 

 ly depend upon the relation of the germ to its en- 

 compassing liquid. Anything that hinders this 

 interchange retards the destruction of the germ 

 in boiling water. In 1877 I add the following 

 remark : 



" It is not difficult to see that the surface of a 

 seed or germ may be so affected by desiccation and 

 other causes as practically to prevent contact be- 

 tween it and the surrounding liquid. The body of 

 a germ, moreover, may be so indurated by time and 

 dryness as to resist powerfully the insinuation of , 

 water between its constituent molecules. It would j 

 be difficult to cause such a germ to imbibe the I 

 moisture necessary to produce the swelling and j 

 softening which precede its destruction in a liquid | 

 of high temperature." 



However this may be — whatever be the state ' 

 of the surface, or of the body, of the spores of J 



Bacillus subtilis, they do as a matter of certainty 

 resist, under some circumstances, exposure for 

 hours to the heat of boiling water. No theoretic 

 skepticism can successfully stand in the way of 

 this fact, established as it has been by hundreds, 

 if not thousands, of rigidly-conducted experi- 

 ments. 



My respondent calls Lis article a " reply." It 

 is the reply which antecedent knowledge would 

 have led me to expect ; but it is not, I submit, 

 the reply which the English public, including the 

 medical profession of England, had a right to 

 expect. It is a reply upon side issues which do 

 not touch the core of the question at all. Let 

 me point out something which demanded a reply, 

 but to which none has been given. Reference has 

 been already made to my " cloud of witnesses," 

 for the interpretation of whose testimony my re- 

 spondent seemed to intimate that he possessed a 

 private key. The true inference from that tes- 

 timony is that it refutes my respondent. But 

 were it not that I wished to follow his instruc- 

 tions formally and scrupulously, and thus deprive 

 him of all opportunity of cavil or complaint, the 

 refutation was unnecessary. The evidence al- 

 ready recorded against him in the industrial arts 

 was simply overwhelming. Not by hundreds, 

 nor by thousands, but by millions, the witnesses 

 might be counted which contradict him. For, 

 what are most of our preserved meats and vege- 

 tables but the results of experiments in which his 

 instructions have been carried out and his state- 

 ments disproved ? Animal and vegetable tissues 

 are placed in tin vessels, each with a small hole 

 in its lid. The tins are boiled, steam issues 

 through the hole, and, after some minutes' boil- 

 ing, the tin is hermetically sealed. This is to 

 all intents and purposes the process described by 

 my respondent before the Pathological Society. 

 Every sound tin thus prepared is therefore a wit- 

 ness against him. I am aware that he has met 

 what he is pleased to call Mr. Huxley's " empty 

 generalities " by stating that the tins of a certain 

 establishment which he visited were boiled for 

 an hour and a half, and, after sealing, were sub- 

 jected to a temperature of 25S° for half an hour. 

 But this is not the universal practice, and mill- 

 ions of tins have been prepared without this sub- 

 sequent superheating. It is idle, moreover, to lay 

 any stress upon this point ; for the substances 

 after having been superheated remain putrescible, 

 though they do not putrefy, or show the slightest 

 tendency or power to generate life. 



To meet this crushing demonstration, my re- 



