318 THE FLOATING-MATTER OF THE AIR. 



six months' exposure to moteless air maintained at a 

 temperature of 90° Fahr., when inoculated with full- 

 grown active bacteria, fills itself in two days with 

 organisms so sensitive as to be killed by a few minutes' 

 -exposure to a temperature much below that of boiling 

 water. But the extension of this result to the desic- 

 cated germinal matter of the air is without warrant or 

 justification. This is obvious without going beyond 

 the argument itself. But we have gone far beyond the 

 argument, and proved by multiplied experiment the 

 alleged destruction of all living matter by the briefest 

 exposure to the influence of boiling water to be a de- 

 lusion. The whole logical edifice raised upon this basis 

 falls therefore to the ground ; and the argument that 

 bacteria and their germs, being destroyed at 140°, must, 

 if they appear after exposure to 212°, be spontaneously 

 generated, is, I trust, silenced for ever. 



Through the precautions, variations, and repetitions 

 observed and executed with the view of rendering its 

 results secure, the separate vessels employed in this 

 inquiry have mounted up in two years to nearly ten 

 thousand. 



Besides the philosophic interest attaching to the 

 problem of life's origin, which will be always immense, 

 there are the practical interests involved in the appli- 

 cation of the doctrines here discussed to surgery and 

 medicine. The antiseptic system, at which I have 

 already glanced, illustrates the manner in which bene- 

 ficent results of the gravest moment follow in the wake 

 of clear theoretic insight. Surgery was once a noble 

 art ; it is now, as well, a noble science. Prior to the 

 introduction of the antiseptic system, the thoughtful 

 surgeon could not have failed to learn empirically that 

 there was something in the air which often defeated the 

 most consummate operative skill. That something the 



