In one respect the development during the War may perhaps have proved to be somewhat disappointing, as it might have been expected that great improvements would be effected in metal construction, leading almost to the abolition of wooden structures. Although, however, a good deal of experimental work was done which resulted in overcoming at any rate the worst of the difficulties, metal-built machines were little used (except to a certain extent in Germany) chiefly on account of the need for rapid production and the danger of delay resulting from switching over from known and311 tried methods to experimental types of construction. The Germans constructed some large machines, such as the giant Siemens-Schukhert machine, entirely of metal except for the wing covering, while the Fokker and Jünker firms about the time of the Armistice in 1918 both produced monoplanes with very deep all-metal wings (including the covering) which were entirely unstayed externally, depending for their strength on internal bracing. In Great Britain cable bracing gave place to a great extent to 鈥榮tream-line wires,鈥?which are steel rods rolled to a more or less oval section, while tie-rods were also extensively used for the internal bracing of the wings. Great developments in the economical use of material were also made in the direction of using built-up main spars for the wings and inter-plane struts; spars composed of a series of layers (or 鈥榣aminations鈥? of different pieces of wood also being used. Castalia started to her feet and confronted him. "Never!" she said. "I will never do it!" Horatia. By-the-by, Mr. Dapple, may I ask your opinion on a much disputed point, where I venture to differ even from my Uncle? What do you think of the Aerolites? 鈥?. That in arched surfaces the centre of pressure at 90 degrees is near the centre of the surface, but moves slowly forward as the angle becomes less, till a critical angle varying with the shape and depth of the curve is reached, after which it moves rapidly toward the rear till the angle of no lift is found. 鈥楩or commercial purposes,鈥?General Sykes has remarked, 鈥榯he airship is eminently adapted for long distance journeys involving non-stop flights. It has this inherent advantage over the aeroplane, that while there appears to be a limit to the range of the aeroplane as at present constructed, there is practically no limit whatever to that of the airship, as this can be overcome by merely increasing the size. It thus appears that for such journeys as crossing the Atlantic, or crossing the Pacific from the west coast of America to Australia or Japan, the airship will be peculiarly suitable. It having374 been conceded that the scope of the airship is long distance travel, the only type which need be considered for this purpose is the rigid. The rigid airship is still in an embryonic state, but sufficient has already been accomplished in this country, and more particularly in Germany, to show that with increased capacity there is no reason why, within a few years鈥?time, airships should not be built capable of completing the circuit of the globe and of conveying sufficient passengers and merchandise to render such an undertaking a paying proposition.鈥? She asked for "the master." The old man was at home, in the little parlour, and Sally showed Mrs. Errington into the room almost without the ceremony of tapping with her knuckles at the door, and then made off to the kitchen to tell Mrs. Grimshaw. The lady's face had scared her. 超碰国产人人做人人爽 Nay, father, said Seth Maxfield, speaking now for the first time, in deprecation of so serious a charge against the "new-fangled days," on which Whitford had fallen. "Nay, no man will say that, nor yet think it. But my notion is, that it may neither be Heaven nor t'other place that has much to do with these kind of fits and screechings. I believe it to be just as Dr. Evans said鈥攁nd he a Welshman himself, you'll remember鈥攚hen he first heard of these doings of David Powell in Wales. Says he, 'It's a epidemic,' says the doctor. 'A catching kind of nervous disease, neither more nor less. And you may any of you get it if you go to hear and see the others. Though forewarned is forearmed in such cases,' says the doctor. 'And the better you understand the real natur' of the disorder, the safer you'll be from it.'" The envelope of this dirigible was rendered airtight by means of internal rubber coating, with a thinner film on the outside. Coal gas, used for inflation, formed a suitable fuel for the engine, but limited the height to which the dirigible could ascend. Such trials as were made were carried out with the dirigible held captive, and a speed of 15 feet per second was attained. Full experiment was prevented through funds running low, but Haenlein鈥檚 work constituted a distinct advance on all that had been done previously. Barbara. What shall we do now? The Santos-Dumont No. 5, which was in reality the modified No. 4 with new keel, motor, and propeller, did the course of the Deutsch Prize, but with it Santos-Dumont made no attempt to win the prize until July of 1901, when he completed the course in 40 minutes, but tore his balloon in landing. On the 8th August, with his balloon leaking, he made a second attempt, and narrowly escaped disaster, the airship being entirely wrecked. Thereupon he built No. 6 with a cubic capacity of 22,239 feet and a lifting power of 1,518 lbs.345 With this machine he won the Deutsch Prize on October 19th, 1901, starting with the disadvantage of a side wind of 20 feet per second. He reached the Eiffel Tower in 9 minutes and, through miscalculating his turn, only just missed colliding with it. He got No. 6 under control again and succeeded in getting back to his starting-point in 29? minutes, thus winning the 125,000 francs which constituted the Deutsch Prize, together with a similar sum granted to him by the Brazilian Government for the exploit. The greater part of this money was given by Santos-Dumont to charities.