550 THE POPULAR SCIENCE MONTHLY, 



labors of Robin, Tr^cul, Onimus, Legros, and a great number of otber 

 observers, are decisive ; but life is the property of these protoplasms ; 

 they depend upon an organized system. In the depths of the organ- 

 ism, and shielded from the air, they toil at the creation of microscopic 

 corpuscles. Place them in contact with purified air, in M. Pasteur's 

 glass globes, and then they would be barren. 



The last objection M. Pasteur has to meet is, that, if the germs of 

 all these microscopic vegetable and animal lives are in the atmosphere, 

 they should be discovered and recognized there. But, in examining 

 the dust of the air microscopically, w^e do not by any means detect all 

 the rudiments of that infinitely minute flora and fauna whose existence 

 is attested by the fermentations and putrefactions of organic matter. 

 M. Pasteur has thus far met this argument only by the evidence of his 

 experiments which prove that, in contact with purified air, neither fer- 

 mentations nor putrefactions are possible. That is strictly sufficient, 

 but we can go farther. It is by no means a sure conclusion that these 

 germs do not exist, because many of them are invisible under the lens. 

 To begin with, we do note with certainty a certain number of species 

 in atmospheric dust. It is therefore an admissible presumption that, 

 if the remaining ones elude our eyes and our microscopes, that merely 

 proves them to be smaller than the observed ones. But, perhaps, the 

 problem ought to be viewed in a different way. We believe that these 

 visible germs are the exceptions, that is, that they are beings already 

 arrived at a certain degree of development, and that, in reality, all 

 true germs are of dimensions forever beyond the reach of microscopic 

 observation, even conceiving lenses to be immensely more powerful 

 than they now are. The microscope barely brings within our range 

 of vision points that measure at least a ten thousandth part of a milli- 

 metre. The primitive germs of life cannot even approach the millionth 

 part of a millimetre. Physics and metaphysics both assure us that we 

 must here give up the hope of measuring and estimating things accord- 

 ing to the powers of our limited senses. An eflfort is needed to pursue 

 with the mind's eye these perpetually-dwindling dimensions, still to 

 go on though the imagination fails in the task, and to realize at last 

 how far removed are the bounds of the microcosm. If the faculty of 

 reaching out beyond the limits of our nature, which is one of the no- 

 blest prerogatives of our intelligence, does not desert us, we attain to 

 the idea of the vital monads of Leibnitz, the organic molecules of Buf- 

 fon, the comj)rehension of existence for primal organisms diffused 

 throughout the world by myriads of myriads, and the conception of 

 the infinitely minute within the infinitely minute. 



Thus, just as the infinite universe through which the spheres roll 

 is filled with invisible particles of a subtile matter to which physicists 

 and astronomers give the name of ether, and which supplies the only 

 key to cosmic phenomena, the finite universe in which organization 

 unfolds itself is thronged with corpuscles no less invisible, forming 



