Document Nj4qydeJX3BMQL95Kva6nYYR

Cleveland 3. B. Coolidge, Jr. CoXXeyville #30 ft** Oicabtr 9, 1960 LlthopOM Light Beaistana We bam Jut ocaqaLetad the examination oX Qllddan'e 15 gradaa of lithoponea which we received reeantly, for light sensitivity. 111 their gradaa ahov excallant raalatanea to ultrarlolet light. We hart two or three gradaa only that ahov a good degree oX light resistance, with mm gradaa quit# severe In tha degree of darkening. Laboratory work oX additions of cobalt are being conducted to dataz-mins, on a aaall scale, tha *lnintsi aaotmt to use. Va should have saas results the early part oX next weak. VB Horn:d cot OFV JBB 0007-SWP-043221 N23149