The catastrophic flood of the Neva, September 10 (21), 1777. So, in what feet it was measured…

The height of one of the most outstanding floods of the Neva on September 10 (21), 1777 is practically not captured on the walls of buildings and structures in St. Petersburg. In this context, the leveling catalog, which reflects more than 700 height marks of this flood, and plans with the location of these marks within St. Petersburg, seems to be absolutely unique and very relevant. The author of the catalog is Friedrich Wilhelm Bauer, quartermaster general, surveyor, cartographer. Work on leveling the flooded urban areas was carried out at the behest of Catherine II. In the leveling catalog of F.V. Bauer notes that the maximum height of the water in the flood of 1777 reached 10 feet 3 inches and that it was measured from the ordinary of the Admiralty footstock. To measure excess F.V. Bauer used the French linear measure, which made it possible to recalculate the maximum flood height to a value of 333 cm.