E.T. Pearson Ltd., who was at 417-445 London Road, made Lactagol, a powdered extract of cotton seed and calcium, which they described as
a valuable preparation for increasing the supply of milk when taken by the expectant mother

Nottingham Evening Post – Tuesday 13 December 1949
Image © Trinity Mirror. Image created courtesy of THE BRITISH LIBRARY BOARD.
The earliest ad for Lactagol on the British Newspaper Archive found so is from 1915:

Western Times – Thursday 21 October 1915
Image © Trinity Mirror. Image created courtesy of THE BRITISH LIBRARY BOARD.

Science Museum Group. Carton of ‘Lactagol’, London, England, 1920-1955. A627904. Science Museum Group Collection Online. Accessed August 29, 2018.
The site acquired by Mitcham Borough Council in 1959.
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