The book by Kondraty Birkin (P.P. Karataev), an almost forgotten Russian writer, offers readers a rare opportunity to feel the atmosphere of palace secrets, intrigues and scandals of Russia, England, Italy, France and other states in the period of the 16th–18th centuries. Four shameful stains on the memory of a man worthy of respect from posterity for his ardent love of science and patronage of the fine arts! Francis de Medici would have every right to the nickname of the Great if, instead of the political sphere, he devoted himself exclusively to scientific or artistic activity.