I offended with your husband? Oh dear no! Why on earth should I be? You ought not to have said that, Castalia. For a long time the tidings of him that reached Whitford were uncertain and conflicting; then they began to arrive at even wider and wider intervals; and, finally, after Mrs. Errington left the town, they ceased altogether to reach the general world of Whitfordians. The real history of the circumstances which induced Mrs. Errington to leave the home of so many years was known to very few persons. It was this: 我要中彩票下载软件 A list of certified pilots of the countries of the world was issued early in 1911, showing certificates granted up to the end of 1910. France led the way easily with 353 pilots; England came next with 57, and Germany next with 46; Italy owned 32, Belgium 27, America 26, and Austria 19; Holland and Switzerland had 6 aviators apiece, while Denmark followed with 3, Spain with 2, and Sweden with 1. The first certificate in England was that of J. T. C. Moore-Brabazon, while Louis Bleriot was first on the French list and Glenn Curtiss, first holder of an American certificate, also held the second French brevet. Can any one wonder that a man like St. Clare should put such questions as these? Well, but you'll manage to make out that I'm in the wrong and you're in the right, somehow or other. 21 Then I said, 'O my Lord, I am old, and cannot go. Send Your angels to bring them.' Rose smiled with tightly-closed lips, and nodded. "To be sure! Poor dear Mrs. Errington鈥擨 mean no disrespect to your mother-in-law, Castalia, who is really a superior woman, only in some things she is as blind as a bat." And again: 鈥業t has before been shown how utterly inadequate the mere perpendicular impulse of a plane is found to be in supporting a weight, when there is no horizontal motion at the time. There is no material weight of air to be acted upon, and it yields to the slightest force, however great the velocity of impulse may be. On the other hand, suppose that a large bird, in full flight, can make forty miles per hour, or 3,520 feet per minute, and performs one stroke per second. Now, during every fractional portion of that stroke, the wing is acting upon and obtaining an impulse from a fresh and undisturbed body of air; and if the vibration of the wing is limited to an arc of two feet, this by no means represents the small force of action that would be obtained when in a stationary position, for the impulse is secured upon a stratum of fifty-eight feet in length of air at each stroke. So that the conditions of weight of air for obtaining support equally well apply to weight of air and its reaction in producing forward impulse. The abnormal needs of the war period brought many British firms into the ranks of Vee-type engine-builders, and, apart from those mentioned, the most notable types produced are the Rolls-Royce and the Napier. The first mentioned of these firms, previous to 1914, had concentrated entirely on car engines, and their very high standard of production in this department of internal combustion engine work led, once they took up the making of aero engines, to extreme efficiency both of design and workmanship. The first experimental aero engine, of what became known as the 鈥楨agle鈥?type, was of Vee design鈥攊t was completed in March of 1915鈥攁nd was so successful that it was standardised for quantity production. How far the original was from the perfection subsequently ascertained is shown by the steady increase in developed horse-power of the type; originally designed to develop 200 horse-power, it was developed and improved before its first practical trial in October of 1915, when it developed 255 horse-power on a brake test. Research and experiment produced still further improvements, for, without any enlargement of the dimensions, or radical alteration in design, the power of the engine was brought up to 266 horse-power by March of 1916, the rate of revolutions of 1,800 per minute being maintained throughout.413 July, 1916, gave 284 horse-power; by the end of the year this had been increased to 322 horse-power; by September of 1917 the increase was to 350 horse-power, and by February of 1918 the 鈥楨agle鈥?type of engine was rated at 360 horse-power, at which standard it stayed. But there is no more remarkable development in engine design than this, a 75 per cent increase of power in the same engine in a period of less than three years. 8 The angels then comforted Adam and Eve, and departed.