“But there are no yeasts in this one; where are the yeasts? There is nothing here but a mass of confused stuff--what is it, what does this mean?” He took the bottle up again and brooded over it with an eye that saw nothing--till at last a different, a strange look of the juice forced its way up into his wool-gathering thoughts. “Here are little gray specks sticking to the walls of the bottle--here are some more floating on the surface--wait! No, there aren’t any in the healthy stuff where there are yeasts and alcohol. What can that mean?” he pondered. Then he fished down into the bottle and got a speck, with some trouble, into a drop of pure water; he put it before his microscope.... His moment had come. No yeast globes here, no, but something different, something strange he had never seen before, great tangled dancing masses of tiny rod-like things, some of them alone, some drifting along like strings of boats, all of them shimmying with a weird incessant vibration. He hardly dared to guess at their size--they were much smaller than the yeasts--they were only one-twenty-five-thousandth of an inch long! That night he tossed and didn’t sleep and next morning his stumpy legs hurried him back to the beet factory. His glasses awry on his nearsighted eyes, he leaned over and dredged up other samples from other sick vats--he forgot all about Bigo and thought nothing of helping Bigo; Bigo didn’t exist; nothing in the world existed but his sniffing curious self and these dancing strange rods. In every one of the grayish specks he found millions of them.... Feverishly at night with Madame Pasteur waiting up for him and at last going to bed without him, he set up apparatus that made his laboratory look like an alchemist’s den. He found that the rod-swarming juice from the sick vats always contained the acid of sour milk--and no alcohol. Suddenly a thought flooded through his brain: “Those little rods in the juice of the sick vats are alive, and it is _they_ that make the acid of sour milk--the rods fight with the yeasts perhaps, and get the upper hand. They are the ferment of the sour-milk-acid, just as the yeasts must be the ferment of the alcohol!” He rushed up to tell the patient Madame Pasteur about it, the only half-understanding Madame Pasteur who knew nothing of fermentations, the Madame Pasteur who helped him so by believing always in his wild enthusiasms.... It was only a guess but there was something inside him that whispered to him that it was surely true. There was nothing uncanny about the rightness of his guess; Pasteur made thousands of guesses about the thousand strange events of nature that met his shortsighted peerings. Many of these guesses were wrong--but when he did hit on a right one, how he did test it and prove it and sniff along after it and chase it and throw himself on it and bring it to earth! So it was now, when he was sure he had solved the ten-thousand-year-old mystery of fermentation.