Complex sentence: In 1902 he was made squadron commander with the 19th Artillery Regiment, but his real work is done while heading the workshop building precision instruments for the technical artillery section in Paris and promoting the use of telephonic connections to enable the artillery to change fire targets quickly.
Split into simpler sentences: In 1902 he was made squadron commander with the 19th Artillery Regiment. But his real work was done as head of the workshop building precision instruments for the technical artillery section in Paris, and promoting the use of telephonic connections to enable the artillery to change fire targets quickly.