In the early days of aviation in 1910 when Rolls, Egerton, Ogilvie and Grace were flying the open machines at the Aero Club's flying ground at Eastchurch, Grace made the interesting statement that in a few years aircraft design would develop under a continuous flow of invention in the same way as the motor car was then developing. Had Grace lived he would have been astonished at the truth of his prophecy, for the subject known at the Patent Office under the head of “Aeronautics“ has developed into one of the greatest industries in the world, and by the end of the year 1930 the abridgments on Aeronautics had become one of the stoutest volumes in the patent classification. In spite of this growth which marked out the subject for a department of its own, for some inscrutable reason the Patent Office then decided to mix up aircraft with ships and thenceforth have published these two subjects in a single group instead of keeping them separate as before that time.