Hallberg, Josef Henrik, 1874- · New York city, The Moving picture world · leaf 134
Fig. 70 … Fig. 71 128 MOTION PICTURE ELECTRICITY The conditions referred to, and illustrations Figs, 70and 71, are remote and unusual, and could be taken careof by using reflecting mirrors, or glass prisms, but Ithought it best to include them while discussing the di-rect current projector arc. I would…
Motion picture theaters · Electric lighting
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![An illustration from [Electric engineering.] (1902)](https://img.insideoutlibrary.com/img/200/ia-electricengineer03inte-380-238.webp)
![An illustration from [Graphophone patents] (1878)](https://img.insideoutlibrary.com/img/200/ia-graphophonepaten20unit-59-15.webp)
