That was the great thing about Pasteur! When he prepared to take the rabbit out of the hat, to astonish the world, he was absolutely sincere about it; he was a magnificent showman and not below some small occasional hocus-pocus, but he was no designing mountebank. And the public test was set for May and June, that year. Roux and Chamberland--who had begun to see animals that were strange combinations of chickens and guinea-pigs in their dreams, to drop important flasks, to lie awake injecting millions of imaginary guinea-pigs, these fagged-out boys had just started off on a vacation to the country--when they received telegrams that brought them back to their exciting treadmill: COME BACK PARIS AT ONCE ABOUT TO MAKE PUBLIC DEMONSTRATION THAT OUR VACCINE WILL PROTECT SHEEP AGAINST ANTHRAX--L. PASTEUR. Something like that read these wires. They hurried back. Pasteur said to them: “Before the Agricultural Society of Melun, at the farm of Pouilly-le-Fort, I am going to vaccinate twenty-four sheep, one goat and several cattle--twenty-four other sheep, one goat and several other cattle are going to be left without inoculation--then, at the appointed time, I am going to inject _all_ of the beasts with the most deadly virulent culture of anthrax bacilli that we have. The vaccinated animals will be perfectly protected--the not-vaccinated ones will die in two days of course.” Pasteur sounded as confident as an astronomer predicting an eclipse of the sun.... “But, master, you know this work is so delicate--we _cannot_ be absolutely sure of our vaccines--they may kill some of the sheep we try to protect----” “WHAT WORKED WITH FOURTEEN SHEEP IN OUR LABORATORY WILL WORK WITH FIFTY AT MELUN!” Pasteur roared at them. For him just then, there was no such thing as a mysterious, tricky nature, an unknown full of failures and surprises--the misty Infinite was as simple as two plus two makes four to him just then. So there was nothing for Roux and Chamberland to do but to roll up their sleeves and get the vaccines ready. The day for the first injections came at last. Their bottles and syringes were ready, their flasks were carefully labeled--“Be sure not to mix up the first and second vaccine, boys!” shouted Pasteur, full of a gay confidence, as they left the Rue d’Ulm for the train. As they came on the field at Pouilly-le-Fort, and strode toward the sheds that held the forty-eight sheep, two goats and several cattle, Pasteur marched into the arena like a matador, and bowed severely to the crowd. There were senators of the Republic there, and scientists and horse doctors and dignitaries, and hundreds of farmers; and as Pasteur walked among them with his little limp--it was however a sort of jaunty limp--they cheered him mightily, many of them, and some of them snickered. And there was a flock of newspaper men there, including the now almost legendary de Blowitz, of the London _Times_.