Great inventions have been made by Russian scientists and engineers. What were these inventions? What other inventions were made along the same line within that period of time?

2)    By the time Humphry Davy, the British scientist, discovered the voltaic arc in 1811, the
electric arc had been already discovered by Russian scientist V. Petrov on November 23.
1802, but his discovery remained unknown in the West.
3)    In 1877, Thomas Edison improved and later patented the lamp which had been made
by Alexander Lodygin, a young Russian engineer, in 1873
4)    In 1886, K..E. Tsiolkovsky modified an all-metal dirigible, the idea of which had been
put forward by   Mendeleyev in  1875.
5)    By the time two Americans Orville and Wilbur Wright built an aeroplane in 1Э03 the first
aircraft had been already designed by Mozhaisky in 1878 and tested on August 1, 1882.
6)    In 1829, in Russia the Chetepanovs, father and son, improved a steam locomotive which
had been invented by George Stephenson in 1814.