16 Boyhood, Early Schooling, and Teaching 



arranged that each division of his Department — Entomology, 

 Chemistry, Gardens and grounds, Botany, Microscopy, and Statis- 

 tics — should contribute displays in acknowledgment of the "uni- 

 versally-accepted " belief that " to agricultural science and industry 

 belong the attribute of characterizing the leading feature of the 

 world's improvement." " 



The Microscopical Division supplied a collection of " finely- 

 executed water-color drawings" representing a wide variety of 

 subjects, six hundred specimens in all, among which were shown 

 the more common molds, those destructive to vegetation and those 

 of value in preparing cheese, bread, and jellies. Approximately 

 one hundred varieties of vegetable starches were presented in one 

 series; edible and poisonous mushrooms were differentiated; and 

 one series of drawings illustrated such important diseases of 

 plants as pear-tree blight, the black knot of cherry and plum, and 

 the rot of potato. For the first time a " large collection of well- 

 executed drawings of cryptogamic plants" had been brought 

 together: and the collection, it was believed, ^^ would prove "of 

 permanent value to mycological science in America." In 1873^^ 

 Thomas Taylor, the Department's microscopist, had reported ex- 

 aminations made of several plant diseases: hawthorn-blight, 

 potato blight and rot, black knot, orange blight, apple-speck or 

 rot, and onion-rust. Pear blight was omitted, perhaps because he 

 believed that its suspected fungous origin had not been proven. 



Arthur, in his Philadelphia letter to Smith, mentioned no 

 exhibits except his own. He had spent six months at the Cen- 

 tennial; yet his next letter of January 6, 1877, told nothing of 

 interest on mycology but did compliment the young Michigan 

 student "on the very careful and scientific manner in which you 

 have preserved your last season's spec[imen}s. They are," he 

 wrote, " a hundred times more valuable than the ones sent me 

 previously." 



Before he had graduated in 1872 from Iowa Agricultural Col- 

 lege, a compound microscope, a ToUes instrument, had been used 

 in courses there. In the spring (March-June) of 1871, Bessey had 



^^ Repl't of the Comm'er of Agric. for 1876: 7, 12, Washington, Gov't Print. Off., 

 1877. 



^* Thomas Taylor, Microscopic investigations, Rep't of Comm'er of Agric. for 

 1876: 74-76. 



^'' Rep't of the Comm'er of Agric. for 1873: 183-210. 



