After studying chemistry in his father's laboratory and attending lectures by Faraday, Brande, and Hofmann, Robert Warington Jr. became in 1859 an unpaid assistant to Sir John Bennet Lawes at Rothamsted Experimental Station at Harpenden.

[3] Leaving Cirencester in June 1867, Warington was given by Lawes the post of chemist to his manure and tartaric and citric acid works at Barking and Millwall.

His engagement terminated in 1874, but he remained in the Millwall laboratory for two years longer, working on citric and tartaric acids, and ultimately publishing his results in a paper of 70 pages in the 'Journal of the Chemical Society' (1875).

Before settling at Harpenden, he made in the autumn of 1876 a short tour of the German experimental stations.

[1] In 1884 Robert Warrington Jr. married Helen Louisa (1855–1898), third daughter of George H. Makins, M.R.C.S., chief assayer to the Bank of England.