Then all kinds of strange tricks of yellow fever struck Walter Reed. He watched cases of the disease pop up most weirdly in Quemados. A man in a house in 102 Real Street came down with it; then it jumped around the corner to 20 General Lee Street, and from there it hopped across the road--and not one of these families had anything to do with each other, hadn’t seen each other, even! “That smells like something carrying the disease through the air to those houses,” said Reed. There were various other exceedingly strange things about yellow fever--they had been discovered by an American, Carter. A man came down with yellow fever in a house. For two or three weeks nothing more happened--the man might die, he might have got better and gone away, but at the end of that two weeks, bang! a bunch of other cases broke out in that house. “That two weeks makes it look as if the virus were taking time to grow in some insect,” said Reed, to his Commission who thought it was silly, but they were soldiers. “So we will try Finlay’s notion about mosquitoes,” said Walter Reed, for all of the just mentioned reasons, but particularly because there was nothing else for the Commission to do. That was easy to say, but how to go on with it? Everybody knew perfectly well that you cannot give yellow fever to any animal--not even to a monkey or an ape. To make any kind of experiment to prove mosquitoes carry yellow fever you _must_ have experimental animals, and that meant nothing more nor less than human animals. But give human beings yellow fever! In some epidemics--there were records of them!--eighty-five men out of a hundred died of it, in some fifty out of every hundred--almost never less than twenty out of every hundred. It would be murder! But that is where the strong moral nature of Walter Reed came to help him. Here was a blameless man, a Christian man, and a man--though he was mild--who was mad to help his fellow men. And if you could _prove_ that yellow fever was _only_ carried by mosquitoes.... So, on one hot night after a day among dying men at Pinar del Rio, he faced his Commission: “If the members of the Commission take the risk first--if they let themselves be bitten by mosquitoes that have fed on yellow fever cases, that will set an example to American soldiers, and then--” Reed looked at Lazear, and then at James Carroll. “I am ready to take a bite,” said Jesse Lazear, who had a wife and two small children. “You can count on me, sir,” said James Carroll, whose total assets were his searcher’s brain, and his miserable pay as an assistant-surgeon in the army. (His liabilities were a wife and five children.) III