Kazimir Semianovich
(about 1600-after 1651)

 Kazimir Semianovich, an engineer and a well-known theorist in the field of artillery, was born in Belarus. He is mostly known as the author of the book "The Great Art of Artillery" published in Amsterdam in 1650. In that book, Semianovich summed up and developed the experience of the gunnery of that period. The book won success and general recognition all over Europe. Soon after, it was republished by Frenchmen, by Germans and by Englishmen. It became a manual for grenadiers. Peter I also kept this book in his library. Besides that, Kazimir Semianovich discovered the way of making multi-stage rockets. He also invented additional engines for them and stabilizers.