Investigation of the cause of that indistinctness of vision which has been ascribed to the smallness of the optic pencil. By William Herschel, LL.D. F.R.S. Read at the Royal Society, June 22, 1786 - Herschel, William Sir 1738-1822 (printed by J. Nichols, 1786)
English Short Title Catalog, T105394
Reproduction of original from British Library