Well, I'll let ship do all the nitty-gritty, but here are the basics.
The first light, the one Major, is a plano-convex spotlight. It used a plain lense, one side being
flat and smooth, and the other
convex. In operation it is similar to that of a
Fresnel, the lamp is simply moved back and forth. However, the
focal point of the P/C lense is longer, so thus the housing is too. This is how the
stage was lit before the
Fresnel took over. A
Fresnel lense is essentially a P/C with steps cut into the
face. This is a principal that was developed back in 1822 for use in lighthouses, and eventually made it's way to the
stage, and, being more effecient than the P/C it replaced. The early P/C's, such as this one by Major, often had an uneven beam, and the lense sometimes caused a rainbow
effect at the edges of the pool of light. There was also the problem of
filament projection. When the lamp was at the
focal point of the lense, an exact
image of the
filament was projected. It's not like these lights completely and utterly stunk, they just had enough drawbacks that they developed a bad name in the U.S. P/C's are still made today, both with their Original Plano-Convex Lenses and
Pebble-Convex lenses, which instead of being smooth on one side, are stippled to created a softer beam and combate the disadvantages of the older P/C's. P/C's are still used mostly in Europe, and should not be disregarded as a viable choice of
instrument, as the modern P/C's have overcome the problems of their historic counterparts.
As for the other light, it is definatly an older
leko. My first suggestion would be to go to the
strand archive and see if its on there. By the looks, it might be similar to the
conventional 6x9. but never having seen one in person, I can't say.
Congradualtions on the find of these old lights. If for nothing else, their historical value makes them worth keeping. As far as the
leko goes, I don't really think it would be worth rehabbing from a
practical point, but if you wish to from a historical standpoint, I'm sure others an here can help. To me, cleaning it up would be enough. In the case of the P/C, its a unique type of
fixture all to itself and, at the very least, is a great tool to teach others how things "used to be done". In addition, since it uses a true Plano-Convex lense, its beam is very different from modern P/C spots, a fact that might be useful depending on one's needs, especially for certain 'period' looks.