Virology in order to immunize others. In 1717 Lady Mary Wortley Montagu observed the practice in Istanbul and attempted to popularize it in Britain, but encountered considerable resistance. In 1796 Edward Jenner developed a much safer method, using cowpox to successfully immunize a young boy against smallpox, and this practice was widely adopted. Vaccinations against other viral diseases followed, including the successful rabies vaccination by Louis Pasteur in 1886. The nature of viruses however was not clear to these researchers. In 1892, the Russian biologist Dmitry Ivanovsky used a Chamberland filter to try to isolate the bacteria that caused tobacco mosaic
Rhine Campaign of 1796 Germany. By the spring of 1796, Jourdan and Moreau each had 70,000 men while Bonaparte's army numbered 63,000, including reserves and garrisons. François Christophe de Kellermann also counted 20,000 troops in the Army of the Alps holding the area between Moreau and Bonaparte on the western side of modern Switzerland; there was a smaller army in southern France that played no role in the Rhine Campaign. According to plan, Kléber made the first move, advancing south from Düsseldorf against Württemberg's wing of the Army of the Lower Rhine. On 1 June 1796, a division of Kléber's troops led by François