Major Charles Mervyn Barlow commanded 73rd Battery, Royal Field Artillery during the Natal Campaign. The Battery was particularly active at the Battle of Colenso where, with 64th, it did much towards extricating Hart's Irish Brigade from its precarious position in the loop. The two Batteries moved to the right to endeavour to reduce the fire from the Boer centre, which had overpowered 14th and 66th Batteries.

Barlow was commissioned into the Royal Artillery from the Royal Military Academy, Woolwich in 1876. He was promoted to Major in 1893 and assumed command of 73rd Battery in 1898. He took it to South Africa in November of the following year and commanded it until he retired in 1901.