labors of Robin, Trécul, Onimus, Legros, and a great number of other observers, are decisive; but life is the property of these protoplasms; they depend upon an organized system. In the depths of the organism, 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, we 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 fermentations 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 millimetre. 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 according to the powers of our limited senses. An effort 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 noblest prerogatives of our intelligence, does not desert us, we attain to the idea of the vital monads of Leibnitz, the organic molecules of Buffon, the comprehension 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
