鈥極ur fear is that the heathen are starving B鈥攏 and his three children to death! One poor lamb is but a few months old. If I were a man, I would be off to Batala. My friend Mr. H. has written a strong note to an English official at no great distance from Batala,鈥攖here not one Englishman resides,鈥攁nd I feel little doubt that he will bring the strong arm of the law to protect B鈥攏. But the note will not reach till this evening. For eight days B鈥攏 will have been in the fiery furnace. How long can he hold out?鈥? Horatia. Is this the Prince? the Hero? Wilbur Wright. Throughout medi?val times, records attest that10 here and there some man believed in and attempted flight, and at the same time it is clear that such were regarded as in league with the powers of evil. There is the half-legend, half-history of Simon the Magician, who, in the third year of the reign of Nero announced that he would raise himself in the air, in order to assert his superiority over St Paul. The legend states that by the aid of certain demons whom he had prevailed on to assist him, he actually lifted himself in the air鈥攂ut St Paul prayed him down again. He slipped through the claws of the demons and fell headlong on the Forum at Rome, breaking his neck. The 鈥榙emons鈥?may have been some primitive form of hot-air balloon, or a glider with which the magician attempted to rise into the wind; more probably, however, Simon threatened to ascend and made the attempt with apparatus as unsuitable as Bladud鈥檚 wings, paying the inevitable penalty. Another version of the story gives St Peter instead of St Paul as the one whose prayers foiled Simon鈥攁part from the identity of the apostle, the two accounts are similar, and both define the attitude of the age toward investigation and experiment in things untried. A few of his records may be given: in 1910, flying at Laffan鈥檚 Plain in his biplane, fitted with a 50-60 horse-power Green engine, on December 31st, he broke the records for distance and time by flying 185 miles, 787 yards, in 4 hours 37 minutes. On October 31st, 1911, he beat this record by flying for 5 hours 15 minutes,194 in which period he covered 261 miles 810 yards with a 60 horse-power Green engine fitted to his biplane. In 1912, competing in the British War Office tests of military aeroplanes, he won the 锟?,000 offered by the War Office. This was in competition with no less than twenty-five other machines, among which were the since-famous Deperdussin, Bristol, Flanders, and Avro types, as well as the Maurice Farman and Bleriot makes of machine. Cody鈥檚 remarkable speed range was demonstrated in these trials, the speeds of his machine varying between 72.4 and 48.5 miles per hour. The machine was the only one delivered for the trials by air, and during the three hours鈥?test imposed on all competitors a maximum height of 5,000 feet was reached, the first thousand feet being achieved in three and a half minutes. 一道本不卡免费高清在线,色www亚洲免费,在线高清理伦片,国产大香蕉视频播放 The experiments made by the brothers previous to the war had convinced Otto that previous experimenters96 in gliding flight had failed through reliance on empirical conclusions or else through incomplete observation on their own part, mostly of bird flight. From 1871 onward Otto Lilienthal (Gustav鈥檚 interest in the problem was not maintained as was his brother鈥檚) made what is probably the most detailed and accurate series of observations that has ever been made with regard to the properties of curved wing surfaces. So far as could be done, Lilienthal tabulated the amount of air resistance offered to a bird鈥檚 wing, ascertaining that the curve is necessary to flight, as offering far more resistance than a flat surface. Cayley, and others, had already stated this, but to Lilienthal belongs the honour of being first to put the statement to effective proof鈥攈e made over 2,000 gliding flights between 1891 and the regrettable end of his experiments; his practical conclusions are still regarded as part of the accepted theory of students of flight. In 1889 he published a work on the subject of gliding flight which stands as data for investigators, and, on the conclusions embodied in this work, he began to build his gliders and practise what he had preached, turning from experiment with models to wings that he could use. Mrs. Jud. To tell the truth there is a young.... Rumours! Of what nature? Mr Dugald Clerk鈥檚 original two-stroke cycle engine is indicated roughly, as regards principle, by the accompanying diagram, from which it will be seen that the elimination of the ordinary inlet and exhaust valves of the four-stroke type is more than compensated by a separate cylinder which, having a piston worked from the connecting-rod of the power cylinder, was used to charging, drawing the mixture from the carburettor past the valve in the top of the charging cylinder, and then forcing it through the connecting pipe into the power cylinder. The inlet valves both on the charging and the power cylinders are automatic; when the power piston is near the bottom of its stroke the piston in the charging cylinder is compressing the carburetted air, so that as soon as the pressure within the power cylinder is relieved by the exit of the burnt gases through the exhaust ports the pressure in the charging cylinder causes the valve in the head of the power cylinder to open, and fresh mixture flows into the cylinder, replacing the exhaust gases. After the piston has again covered the exhaust ports the mixture begins to be compressed, thus automatically closing the inlet valve. Ignition occurs near the end of the compression stroke, and the working stroke immediately follows, thus giving an impulse to the crankshaft on every down stroke of the piston. If the scavenging of the cylinder were complete, and the cylinder were to451 receive a full charge of fresh mixture for every stroke, the same mean effective pressure as is obtained with four-stroke cycle engines ought to be realised, and at an equal speed of rotation this engine should give twice the power obtainable from a four-stroke cycle engine of equal dimensions. This result was not achieved, and, with the improvements in construction brought about by experiment up to 1912, the output was found to be only about fifty per cent more than that of a four-stroke cycle engine of the same size, so that, when the charging cylinder is included, this engine has a greater weight per horse-power, while the lowest rate of fuel consumption recorded was 0.68 lb. per horse-power per hour.