38. On the Vision of Colours, 
the public, apprehending it to be a singular one, ~ I 
remembered, indeed, to have read in the Philosophi- 
cal Transactions for 1777, an account of Mr, 
Harris of Maryport in Cumberland,* who, it was 
said, ** could not distinguish colours;” but his casé 
appeared to be different from ours. Considering, 
however, that one anomaly in vision may tend to 
illustrate another, I reperused the account; when it 
appeared extremely probable that if his vision had 
been fully investigated, and a relation of it given in 
the first person, he would have agreed with me, 
There were four brothers in the same predica- 
ment, one of whom is now living. Having an ac- 
quaintance in Maryport, I solicited him to pro- 
pose a few queries to the survivor, which he 
readily did (in conjunction with another brother, 
whose vision has nothing peculiar), and from the 
answers transmitted to me, I could no. longer 
doubt of the similarity of our cases. To render it 
still more circumstantial, I sent about twenty speci- 
mens of different coloured ribbands, with direc- 
tions to make observations upon them by day-light 
and candle-light: the result was exactly conformable 
to my expectation. 
It then appeared to me probable, that a consider- 
able number of individuals might be found whose 
.°* A translation of this account, to whichis annexed 
the extraordinary case of M. Colardeau, is inserted in 
Rozier: Observations sur la Physique, Sc. p. 87. E.H, 
