The article on nanotubes as light sources was frustratingly sketchy. Any photometric laboratory with a wattmeter could compare the nanotube unit to another light source in a few minutes. It is tempting to think that the heating effect, which must be close to that from a blackbody radiator, and the “electronic effect,” which is undoubtedly a selective radiator, could give a lumen-per-watt efficacy higher than that in incandescence. I hope you keep us posted on this development with some specific data.

Bill Jones
Orange, Calif.