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).
Guide on the types and properties of anti-freezing mixtures for use in motor cars.
| Identifier | ExFiles\Box 151\3\ scan0016 | |
| Date | 15th September 1914 | |
| (180 H) (W.W. 754. 15-9-14) G. {Mr Griffiths - Chief Accountant / Mr Gnapp} 0768. ANTI-FREEZING MIXTURES TO USE. Editor The Automobile:- I am desirous of obtaining information in reference to freezing mixtures, for motor cars. Will you kindly advise me regarding any literature which you have published on this subject? Toronto, Ont. J.C.Royce. We have published no literature on the subject but the main features of the different freezing mixtures may be briefly told. There are three anti-freezing solutions that have been used extensively and which have proved satisfactory. They are alcohol, glycerine, and calcium chloride. There are many others that have a low enough freezing point but are objectionable because they evaporate quickly, do not carry the heat away fast enough, corrode the parts of the cooling system, leave a deposit in the radiator, do not flow freely or are too expensive. A solution of alcohol in water most nearly fills the requirements of a perfect anti-freezing mixture. Either wood or denatured alcohol may be used and can be purchased at any drug store for about 60 cents a gallon. The advantages of the alcohol are that it is easily handled and has no corrosive action on the metal parts of the cooling system. Wood alcohol has a lower freezing point than the denatured product so a weaker solution is needed for any given condition, but this advantage is more than offset, in most cases, because in the former more is lost by evaporation, due to its lower boiling point. This necessitates adding wood alcohol more often than is the case when denatured is used, in order to keep the solution up to the normal strength. The percentage of alcohol, by volume, to give a certain freezing point can be obtained from the curve Fig. 2, or from the table below: Freezing Point. Denatured. Wood. Degrees Alcohol. Water. Alcohol. Water. Fahrenheit. Per Cent. Per Cent. Per Cent. Per Cent. -10. 28 72 17 83 0. 40 60 24 76 10. 52 48 31 69 20. 63 37 38 62 So little water is lost by evaporation that it is | ||