Recent developments in drawing by the aid of projection apparatus used on the house lighting system .. (1912)
Gage, Simon Henry, 1851-1944 · n.p. · leaf 37
Fig. 15 HB^^KS … Fig. 16 DRAWING WITH PROJECTION APPARATUS I97 Plate XXV ig. IS. Spencer Lens Companys apparatus for drawing with the micro-scope. This consists of a small arc lamp with the proper wiring, rheo-stat and connections for the house electric supply. The lamp hasall the adjustments, and the condenser…
Lantern projection · Projection · Drawing
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