Explanatory reading March 13, 1886, in the Imperial Agricultural Museum. With 35 drawings in the text. St. Petersburg Public Use. 1886. 42p.:Il. Solid semi-leather binding, enlarged format. Chernyaev Valerian Vasilievich (1844 - 1892) - specialist in agricultural machines. The son of a professor of botany, he received a special education at the Petrovsky Agricultural Academy, where he entered at the end of the course at Kharkov University, in the natural department. He contributed to the widespread acquaintance with improved agricultural tools and machines among the owners, also rendered many services to the development of their actual application in practice and the organization of their production and sales. The main attention was paid to earthworking tools and seeders, then to sortings, branches, hammers, hay presses. He was known for his public lectures at the Agricultural Museum (SPb.) and at various agricultural exhibitions, where he was a competent specialist in agricultural engineering. For 24 years, the employee of the “Agricultural Newspaper”, in which he placed up to 500 articles and almost the same number of answers to the requests of the owners.