at average speeds of from four to twelve miles an hour respectively between the two oak trees above-named on the Test Hill in Richmond Park:—

The following speeds were attained in experiments held on the above-mentioned portion of this hill during the winter. The cars had flying starts:—

Another hill which is fairly convenient to London, and is often used to test cars, is Netherhall Gardens, leading out of Fitzjohn's Avenue, near Swiss Cottage Station. This hill has been specially surveyed for the purpose of this book, and a contour is shown opposite.

Many readers of the 'Badminton Library' will desire to know of cars which can be used where petrol is unobtainable. Messrs. Roots and Venables in England, Koch and others on the Continent, have for a long time studied the problem of the paraffin internal combustion engine. The advantages of motor-cars fitted with these engines for use in hot climates and places where petrol cannot be purchased are obvious. Ordinary lamp-paraffin can be found in almost any part of the globe.