Document 1QOYKGDbjqgerkgpMZgJxGpm

January 6, 19^1 Dr. George Calingaert Sthyl Gasoline Corporation 1600 West Sight Mile Hoad Detroit, .Michigan Dear Cal: Herbert Neal has bean here and has been of considerable assistance to us in outlining the service requirements and maintenance operations on the stove. One further bit of information that we have asked him to get for us 3 your method for preparing the filter discs for analysis. Our previous experience with materials of this type leads us to believe that extraction with hot 1:1 nitric acid will usually remove all of the lead and eliminate the necessity for digestion with hydrofluoric acid which is usually heavily contaminated. One further point, what chemical method did you use for analysis for bromine and normally, how do you calculate your results of combustion or exhaust mixtures in terms of l8ad bromide or lead chloride? Cordially, 'WM:vr Willard 13achi K E 0009517