Solarclipse lamps were one of the most impressive and attractive lamps of their time. The design originated in France and was produced there as the Besnard Lamp. The advertising piece below shows a lamp with a dimming mechanism, which moved a dimmer in front of the acetylene gas burner, cutting the output of the lamp to only what was projected forward by the reflector. These lamps were quite expensive as the construction was extraordinary and the convex ground lens, which is over an inch thick, serves as a magnifier.
The ad below from the Cycle and Automobile Trade Journal below, dated August 1908. See a pair of these lamps on the preceding post showing us a Lozier Briarcliff. The Old Motor photos.