Page:Microbe Hunters.djvu/270

mer of 1889 came, the days grew hot; the year before the cattlemen had complained bitterly about their losses. It was urgent to do something, even the government saw that. The Department of Agriculture loosened up with a good appropriation, and Dr. Salmon, the Director, directed that the work begin—luckily he knew so little about experiments that his direction never bothered Smith in the slightest.

With Kilborne, Theobald Smith now built an outlandish laboratory, not between four walls but under the hot sky, and the rooms of that place of science were nothing more than five or six little dusty fenced off fields. On June 27 of 1889, seven rather thin but perfectly healthy cows came off a little boat which brought them from farms in North Carolina, from the heart of the Texas fever country, where it was death for northern cattle to go. And these seven cows were, one and all of them, decorated, infested and plagued by several thousands of ticks, assorted sizes of them, some so tiny they needed a magnifying glass to be seen—and then there were splendid female ticks half an inch long, puffed up with blood sucked from their long-suffering hosts.

Into securely fenced Field No. 1, Smith and Kilborne drove four of these tick-loaded southern cattle, and with them they put six healthy northern beasts— "Pretty soon the northerners will be getting the ticks on them too, they have never been near Texas fever. . . . They are susceptible, and then. . . ?" said Smith. "And now for a little trick to see if it is the ticks we have to blame!"

So Theobald Smith did his first little trick—call it an experiment if you wish—it was a stunt a shrewd cattleman might have thought of if he hadn't been too busy to try it; it was an experiment all other American scientists considered it silly to attempt. Smith and Kilborne set out to pick off, with their hands, every single tick from the remaining three southern