PLATE XI 
Electron gun; 
a hot filament of tungsten ——> 

Condenser lens (Magnet) ——> 
Air lock to introduce 
specimen and mechanical 
stage — 
Objective lens 
(Magnet) — 
Window for viewing low 
magnification on _ inter- 
nediate fluorescent screen——} 
Projector lens 
(Magnet) — | 
Windows for viewing final 
image on fluorescent screen—> 
Air lock for photographic 
plate 
THe ELecrron Microscopg (R.C.A.) 
