 In 1876, Adolf Mayer, who directed the Agricultural Experimental Station in Wageningen, was the first to show that what he called "Tobacco Mosaic Disease" was infectious.He thought that it was caused by either a toxin or a very small bacterium.Later, in 1892, the Russian biologist Dmitry Ivanovsky (1864–1920) used a Chamberland filter to study what is now known as the tobacco mosaic virus.