From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Copy of a letter from E.A. Evans Esq. detailing the chemical analysis of a soft black deposit sample.
| Identifier | ExFiles\Box 145\2\ scan0082 | |
| Date | 29th October 1935 guessed | |
| Copy of letter written by E.A.Evans Esq.to Messrs.Rolls Royce Ltd., Derby. For the attention of Mr.Rowbotham. Dear Sirs, We have examined the sample of soft black deposit which you showed me when I was at your Works recently. If you remember I expressed a desire to have it in spite of your assurance that it was of the usual type which you always found. Our analysis is as follows:- Free Oil 22.9% Oxidised oil soluble in benzene 1.1% Oxidised oil insoluble in benzene 16.7% Mineral matter 59.3% ----- 100.0 Analysis of Mineral matter:- Silica 8.4% Lead oxide 31.2% Copper oxide 14.6% Tin oxide Trace Iron & aluminium oxides 39.6% Chromium oxide 1.0% Lime 2.8% You will observe that the mineral matter is 60% approximately, consequently there is not much left for oil decomposition products. It is interesting to note that the mineral matter contains 31% of lead oxide. The origin of this is obvious. It is also interesting to note the very tiny amount of tin oxide and chromium oxide. ---------- | ||