In the intervals of this hectic collecting and lecturing he shut himself in his laboratory with his stews and his microscopic animals, and made long experiments to show that these beasts obey nature’s laws, just as men and horses and elephants are forced to follow them. He put drops of stews swarming with microbes on little pieces of glass and blew tobacco smoke at them and watched them eagerly with his lens. He cried out his delight as he saw them rush about trying to avoid the irritating smoke. He shot electric sparks at them and wondered at the way the little animals “became giddy” and spun about, and quickly died. “The seeds or eggs of the little animals may be different from chicken eggs or frog’s eggs or fish eggs--they may stand the heat of boiling water in my sealed flasks--but otherwise these little creatures are really no different from other animals!” he cried. Then just after that he had to take back his confident words.... “Every beast on earth needs air to live, and I am going to show just how _animal_ these little animals are by putting them in a vacuum--and watching them die,” said Spallanzani to himself, alone one day in his laboratory. He cleverly drew out some very thin tubes of glass, like the ones Leeuwenhoek had used to study his little animals. He dipped the tube into a soup that swarmed with his microbes; the fluid rushed up into the hair-fine pipe. Then Spallanzani sealed off one end of it, and ingeniously tied the other end to a powerful vacuum pump, and set the pump going, and stuck his lens against the thin wall of the tube. He expected to see the wee animals stop waving the “little arms which they were furnished to swim with;” he expected them to get giddy and then stop moving.... The pump chugged on--and nothing whatever happened to the microbes. They went nonchalantly about their business and did not seem to realize there was such a thing as life-maintaining air! They lived for days, for weeks--and Spallanzani did the experiment again and again, trying to find something wrong with it. This was impossible--nothing can live without air--how the devil do these beasts breathe? He wrote his amazement in a letter to his friend Bonnet: “The nature of some of these animalcules is astonishing! They are able to exercise in a vacuum the functions they use in free air. They make all of their courses, they go up and down in the liquid, they even multiply for several days in this vacuum. How wonderful this is! For we have always believed there is no living being that can live without the advantages air offers it.” Spallanzani was very proud of his imagination and his quick brain and he was helped along in this conceit by the flattery and admiration of students and intelligent ladies and learned professors and conquering kings. But he was an experimenter too--he was really an experimenter first, and he bent his head humbly when a new fact defeated one of the brilliant guesses of his brain.