Chapman lived in Mexico for many years and became an expert on the stamps of that country. He was one of the collectors that Edward Stanley Gibbons visited on his travels as reported in the pages of Stanley Gibbons Monthly Journal in 1895. Near the end of his life, Chapman helped the firm of Stanley Gibbons compile their listing of Mexican stamps and was a frequent correspondent with the philatelic press
In his later years he was bed-ridden.
32nd United Kingdom Parliament. 33rd United Kingdom Parliament. 34th United Kingdom Parliament.
35th United Kingdom Parliament.
36th United Kingdom Parliament. 37th United Kingdom Parliament]
He unsuccessfully contested the Perth constituency in 1906 and January 1910, and the Greenock constituency in December 1910 and in 1918, but was elected as Member of Parliament (Member of Parliament) for Edinburgh South at the 1922 general election (he was chosen as Unionist candidate for that seat over Katharine Stewart-Murray, Duchess of Atholl) and held the seat until he stepped down at the 1945 general election.
