Physical description

Part of a series entitled “Optical Munitions - School of Natural Philosophy, 1942-1945”. Black and white photo of man, possibly E. R. Johnson, examining rectangular glass “sandwich” block in light. N.B. As at time of writing it is not certain that the “man” pictured in nos. 147 and 149 is the same individual as pictured in no 140. (EGM. 11/11/99)

Inscriptions & markings

In ink on lower left hand corner : “29”.