Several aerial mail routes are now in operation on both sides of the Atlantic. The first regular service of this character in America was begun May 15, 1918, between New York and Washington, and during the first year carried 7,720,840 letters, with few accidents and no fatalities. The first year of service cost the Government $137,900, and the sale of aeroplane mail stamps during the same period yielded a revenue of $159,700. Out of 1,261 possible trips on this route, 1,206 were undertaken, and only fifty-five were abandoned on account of unfavorable weather. During 1919 the Post Office Department not only established other aerial routes, but relegated the aerial mail service to the ranks of the commonplace by reducing the postage on letters carried by aeroplane to the ordinary first-class rate of two cents an ounce. In Europe lines of fast aeroplanes carrying mails, passengers, and freight daily over regular routes are becoming part of the established order of things. The operators of a line between London and Paris, which was inaugurated in November, 1919, are now planning to establish an hourly service. Some of these lines have been equipped with wireless telephony, so that the pilots can keep in constant communication with numerous stations of the company along the route, and also with one another. They are thus able to obtain, among other things, current information about the prevalence of fog or other atmospheric conditions at points ahead of them. Presumably the passengers who patronize the aeroplane express will also, eventually, enjoy the use of the wireless telephone _en route_. In connection with the new air routes suitable landing grounds, for regular or emergency use, are being laid out at short intervals; the ideal aimed at, for the present, being the so-called “ten-mile chain”; i. e., a series of emergency landing grounds about ten miles apart. From ordinary flying levels a pilot on such a route can always glide to one of these grounds in case his motor fails. The landing grounds will be utilized, under certain restrictions, for grazing cattle and for agricultural purposes, to help cover the cost of rental and maintenance. During 1919 the British Government established a chain of landing grounds in Africa, all the way from Cairo to the Cape.