Two letters to James Dinwiddie from William Mackintosh Esq.
Plane Mirrors; Archimedes; Gravity
Optics, No. 1-3
Optics
One letter to James Dinwiddie from Ian Wood
One letter to James Dinwiddie from Dudley Adams
One letter to James Dinwiddie from Dr Blacklock
One letter to James Dinwiddie from D Burges