Tolong jelaskan mengenai Peta dari Peter Carl Ludwig Schwarz

[English: Amur catalog entry of 2 Russian maps appears in the Great Britain, India Office (1878) book at p. 511 in the section "Asiatic Russia" [noted above] as: "The Amur. KAPTA Map of the Region of the AMUR with the upper parts of the Lena and Yenisei and the Island of Saghalin Constructed from the observation of the Siberian expedition of the Imperial Russian Geographical Society by Ludwig Schwarz astronomer to the expedition St Petersburg 1861 In Russian Scale 1 1,680,000 or about 27 miles to 1 inch on 7 sheets in a cover size of each 25 inches by 31. Another edition dated 1864."]