International Library of Technology · Scranton, International Textbook Co. · leaf 457
Fig. 57. the ordinary styles of arc lamp are not suitable, becausesuch lamps are not of the focusing type. For projectionwork, it is necessary to keep the arc in a fixed position; insome cases this is accomplished by hand feeding, while inothers the feeding is automatic. In Fig. 57, {a) showsan…
Electrical engineering
Internet Archive · Boston Library Consortium · Public Domain Mark 1.0. Free to use for anything.
![An illustration from [Electric engineering.], 1902, leaf 457](https://img.insideoutlibrary.com/img/1024/ia-electricengineer03inte-457-286.webp)
