[27] Sanders' Hereford History, p. 348. [28] The Prairie Farmer, Feb. 1, 1885, p. 84. [29] Sanders' History of Hereford Cattle, p. 348. [30] Sander's History of Herefords, pp. 352, 357. [31] The Country Gentleman, July 30, 1857. [32] " " " 1858. [33] The Prairie Farmer, June 7, 1885, p. 372 [34] Rossland Park Stock Farm at Ashkum, Illinois. Prairie Farmer Nov. 14, 1885, p. 741. [35] Cultivator and Country Gentleman, 1875. [36] The Prairie Farmer, 1885. [37] Sale Catalog of Anderson and Findley, 1901. VI. CATTLE PLAGUES[38] "In 1882, Dr. Salmon of the Bureau of Animal Industry, became convinced, from the experimental evidence at his command, that certain disease germs produced a chemical substance during their growth and multiplication which, if injected into the tissues of an animal, would induce immunity from a disease that these germs cause. In other words, he thought that the liquid in which the bacteria were grown in the laboratory might be used after the bacteria had been killed or removed, to protect animals from the disease caused by these specific bacteria. "The first experiment made at that time with fowl cholera failed to confirm the theory. Later experiments with hog cholera bacillus gave unmistakable proof of its correctness. The results were first published in 1886 and additional evidence was published the following year. "Many cattlemen have been prejudiced against the tuberculin test and have objected to it, due to inaccurate or greatly exaggerated statements as to the damage it caused to the cattle on which it was used. Those who have had most experience with tuberculin have consequently failed to observe any injurious effects following its injection into healthy cattle. With cattle that are affected with tuberculosis, it produces a fever which lasts only a short time, and in the great majority of cases, the effects disappear within forty-eight hours after the administration of the tuberculin. The cases of abortion following the tuberculin test have not been numerous, even when cows were tested within a very short time before the normal time of calving. The few cases that have occurred may be explained by the fact that abortion in cattle is a very common occurrence and that it would have happened even though the test had not been applied and that it was a coincidence. "From the investigations and observations made, the following conclusions may be safely drawn: "1. The tuberculin test is an accurate method of determining the presence of tuberculosis in an animal. "2. By the use of tuberculin such animals as are affected with the disease may be detected and removed from the herd. "3. It has no injurious effects. "4. Comparatively small numbers of cattle which have aborted, suffered ill health, or fell off in flesh after the tuberculin test was made, were either diseased before the test was made or were affected by some other cause other than that of the tuberculin."