Ill, — ^THE RISE OF SCIENCE IN AGRICULTURE 



c. 



THEOBALD SMITH AND TEXAS FEVER 



CDespite the gloomy predictions of practical men and scientists alike 

 in the early 1880's, agricultural research began to pay off. Just as the 

 development of bacteriology in Europe had its agricultural side, Amer- 

 ican scientists in the Department of Agriculture eventually demonstrated 

 that a fruitful attempt to solve a practical problem could result in a 

 basic contribution to knowledge. The most conspicuous early accom- 

 plishment of the Department came when a team of scientists of various 

 specialties working in the Bureau of Animal Industry under the direc- 

 tion of Theobald Smith solved a problem of pressing importance to the 

 post-Civil War cattle empire and at the same time proved the role of 

 the secondary host in the transmission of disease. The colorful open- 

 range cattle industry with its long drive of millions of animals from the 

 fever-infected South to the susceptible North was quite as close to the 

 scientific frontier as it was to the geographic frontier. For instance, com- 

 pare the pattern of organization and the relation of science to practical 

 results as shown in the following example to the pattern described in 

 industry by Langmuir. (Hans Zinsser, "Biographical Memoir of Theo- 

 bald Smith, 1859-1934," National Academy of Sciences, Biographical 

 Memoirs, XVII [1937], 261-303.)] 



When Smith, in association with Kilborne, first approached the 

 problem experimentally (1889), there was already some information 

 about this disease and interest in it was stimulated by its great economic 

 importance. 



There had been, for a long time, an impression among cattle ranch- 

 ers, vague but persistent, that ticks were in some manner related to the 

 infection. In 1885, the geographical distribution of the disease had been 

 approximately established by Salmon and its northern limits defined. In 

 1889, Curtice, the entomologist of the Bureau of Animal Industry (4th 

 and 5th Annual Reports, Bureau Animal Industry, p. 436) spoke of an 

 experiment carried out in the Chicago Stockyards, in which five cows 

 were placed into a pen in which Texas cows had been held, with the 

 result that four of them died of the cattle fever. This experiment had 

 been suggested by the "oft repeated experiment of allowing native cattle 

 to live in the trail of Texas cattle." A similar experiment was reported 

 in the same year by Kilborne but, in this attempt, northern cattle were 

 mixed, in one pen, with southern cattle rendered free of ticks — while 

 in another pen the ticks were left on the infected animals. The result 

 was no infection in the former, death of the animals in the latter. Again, 

 in the same year. Smith, undoubtedly working in close association with 

 his colleagues, described (Medical News, Philadelphia) the little bodies 

 in the red cells of infected cattle which he later (1891) recognized as 

 protozoa and eventually named Prioplasma Bigeminum. In announcing 

 this discovery. Smith with the fairness and generosity of character to 

 which "priority" squabbles were abhorrent suggests that these bodies were 



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