Complex sentence: Rakhaldas joined the indian museum in Calcutta, as an Assistant to the Archaeological Section in 1910 and the Archaeological Survey of India as Assistant Superintendent in 1911 and was promoted to the rank of Superintending Archaeologist in 1917.
Split into simpler sentences: Rakhaldas joined the Indian museum in Calcutta as an Assistant to the Archaeological Section in 1910. He joined the Archaeological Survey of India as Assistant Superintendent in 1911, and was promoted to the rank of Superintending Archaeologist in 1917.