Edward Jenner and Vaccination.--The civilized world owes much to Edward Jenner, the discoverer of vaccination against smallpox. Born in Berkeley, a little town of Gloucestershire, England, in 1749, as a boy he showed a strong liking for natural history. He studied medicine and also gave much time to the working out of biological problems. As early as 1775 he began to associate the disease called cowpox with that of smallpox, and gradually the idea of inoculation against this terrible scourge, which killed or disfigured hundreds of thousands every year in England alone, was worked out and applied. He believed that if the two diseases were similar, a person inoculated with the mild disease (cowpox) would after a slight attack of this disease be immune against the more deadly and loathsome smallpox. It was not until 1796 that he was able to prove his theory, as at first few people would submit to vaccination. War at this time was being waged between France and England, so that the former country, usually so quick to appreciate the value of scientific discoveries, was slow to give this method a trial. In spite of much opposition, however, by the year 1802, vaccination was practiced in most of the civilized countries of the world. At the present time the death rate in Great Britain, the home of vaccination, is less than .3 to every 1,000,000 living persons. This shows that the disease is practically wiped out in England. An interesting comparison with these figures might be made from the history of the disease in parts of Russia where vaccination is not practiced. There, thousands of deaths from smallpox occur annually. During the winter of 1913-1914 an epidemic of smallpox with more than 250 cases broke out in the city of Niagara Falls. This epidemic appears to be due to a campaign conducted by people who do not believe in vaccination. In cities and towns near by, where vaccination was practiced, no cases of smallpox occurred. Naturally if opposition to vaccination is found nowadays, Jenner had a much harder battle to fight in his day. He also had many failures, due to the imperfect methods of his time. The full worth of his discovery was not fully appreciated until long after his death, which occurred in 1823. [Illustration: Louis Pasteur.] Louis Pasteur.--The one man who, in biological science, did more than any other to directly benefit mankind was Louis Pasteur. Born in 1822, in the mountains near the border of northeastern France, he spent the early part of his life as a normal boy, fond of fishing and not very partial to study. He inherited from his father, however, a fine character and grim determination, so that when he became interested in scientific pursuits he settled down to work with enthusiasm and energy.