Measurement of the room temperture R(1) line width of forty-two rubies.

Accurate measurement of the room temperature R(1) fluorescent line width of forty-two ruby laser crystals has been made using a pressure-scanned Fabry-Perot etalon. In forty-one of these rubies the chromium content was nearly the same, and the R(1) line width for all was 5.0 +/- 0.3 A, in agreement with present theories.

Ionic polishing of optical surfaces.

The controlled removal of material from the surface of insulators has been observed by using a positive ion beam. In the energy range 0.5-2.0 MeV the sputtering yield was observed to be unity. The application of this technique to the manufacture of high quality optical surfaces is discussed.