Document ZrX1m3dkGLL4zrBO23KNyexp

. ETHYL CORPORATION RESEARCH LA BORA TO RI ES 1600 W EST EI GHT M I LE ROAD FERNDALE 20, DETROIT, MICHIGAN March 11, 1952 Dr. Robert A. Kehoe College of Medicine University of Cincinnati Eden Avenue Cincinnati 19, Ohio Dear Bobs To give you some background for discussion here next week on lead particles in exhaust gas, here is an interim report on one of our two projects on this subject, together with two photographs which came along too late to be included in the report. These are photographs of microscope slides exposed in the same manner as those in the report, and photographed at 500 magnifications. They show rather strikingly the difference of character of the particles collected during steady operation at 30 m.p.h. road load and during acceleration. In addition, we have another project under Ellis Rifkin dealing with electrostatic precipitation of particles in the exhaust of a single-cylinder engine. This has given some interesting results which we shall be ready to spread before you when you get here. - Sincerely yours, HAB:lt KE 0A < VX jb H. A. Beatty t--