Pasteur, Louis (1822-95) French microbiologist and chemist. Autograph Letter Signed ("L. Pasteur"), one page, in French, 8¼ x 5¼ inches, n.p., March 23, n.y. To an unknown correspondent, Pasteur writes, " Dear Sir, I have begun tests on the bulb of the dog. The test will be less certain than if it had not died a violent death. A dog that has died of rabies always has a rabid bulb. Before death it is not always so. Sincerely yours, L. Pasteur." Very good; some age wear and two tape repairs to horizontal fold on verso.
Beginning in 1880, Pasteur worked on finding a vaccination to prevent rabies. The "bulb" to which he refers is the swelled-out portion of the medulla oblongata, which unites the brain and the spinal cord. He produced the first vaccine for rabies by growing the virus in rabbits, then weakening it by exposing the rabid spinal cords to the air. He first tested his vaccine on a human in 1885: a nine-year-old boy named Joseph Meister who had numerous deep bites. Pasteur gave him 13 injections of rabbit medulla homogenate--one per day--and the boy survived. On March 1, 1886, Pasteur presented a paper to the French Academy of Sciences documenting the inoculation of 350 people, only one of which had failed, and concluded that a rabies vaccine establishment was needed. From the international donations he received, he opened the Institut Pasteur in Lille in November 1888.
Estimated Value $6,000 - 8,000.
Scientists and Engineers