From June 9th, 1831 John's occupation was Second Lieutenant for Madras Artillery. He was promoted from this position on May 22nd, 1840.
From April 22nd, 1840 his occupation was Lieutenant for Madras Artillery. He was promoted from this position on June 9th, 1846.
From June 9th, 1846 his occupation was Brevet Captain for Madras Artillery. He was promoted from this position on May 11th, 1854.
From May 11th, 1854 his occupation was Captain for Madras Artillery. He was promoted from this position on September 17th, 1854.
From September 17th, 1854 his occupation was Brevet Major for Madras Artillery. He retired on May 30th, 1858.
His occupation was Reired Major for H M Indian Army.