Cyclopedia of applied electricity : a general reference work on direct-current generators and motors, storage batteries, electrochemistry, welding, electric wiring, meters, electric lighting, electric railways, power stations, switchboards, power transmission, alternating-current machinery, telegraphy, etc. (1916)
American Technical Society · Chicago : American Technical Society · leaf 421
Fig. 87. Bunsen Screen and Sight Box Fig. 86 shows a complete photometer with a Lummer-Brodhunscreen, while Fig. 87 shows a Bunsen screen and sight box. In Fig.86, the lamps are shaded by means of curtains so as to leave only a
Electrical engineering
Internet Archive · Northeastern University Library · Public Domain Mark 1.0. Free to use for anything.
