The colors of Dickinson were derived from the symbols the two literary societies at Dickinson adopted in the 18th century: the Belles Lettres Society was represented by a red rose, whereas the Union Philosophical Society was represented by a white rose.
Citations in the World Almanac (listed by cover date; color information is from the previous year): red/white (1895-1935)
Dickinson College began to use an academic costume system of its own design on 13 June 1893, and was an early client of academic costume manufacturer Cotrell & Leonard, according to “The Cap and Gown in America”, a May 1893 article in The University Magazine written by the Director of the Intercollegiate Bureau of Academic Costume (IBAC), Gardner Cotrell Leonard. The Cotrell & Leonard firm was also the “depository” of the IBAC.
Two years later, Dickinson adopted the 1895 Intercollegiate Code of Academic Costume, which stipulated that the hood lining of a college or university should display the school’s colors in a pattern distinctive to that school. According to Concerning Caps, Gowns and Hoods: Bulletin 17 (1902), Dickinson College was still a client of academic costume manufacturer Cotrell & Leonard, which means the IBAC no doubt assigned a hood lining pattern to Dickinson at some point between 1895 and 1902 – probably in 1895. But no description of Dickinson’s hood was given in either source.
The first definitive and complete IBAC description of the college’s hood lining was in a 1927 IBAC list where it was stated to be cardinal with a white chevron (cardinal being the shade of Dickinson’s red according to the IBAC).
The hood linings the IBAC assigned to Dickinson (cardinal with a white chevron) and Radcliffe College (crimson with a white chevron) were very similar and difficult to distinguish. Today this problem has been resolved because Radcliffe now uses Harvard academic gowns and hoods.