|The 150th Birth Anniversary of the pioneering
(1828-1870) Friedrich Wilhelm Ernst Albrecht von Graefe was commemorated
in this FDC issued by West Berlin in 1978. Amongst his many discoveries are
Graefe's sign (failure of the upper lid to follow a downward movement of the
eyeball when the patient changes his or her vision from looking up to looking
down) and Graefe's knife (knife designed for cataract extraction).