WAR BALLOON.

Dominion, Volume 1, Issue 241, 4 July 1908, Page 5

WAR BALLOON.

WE DOORS' FLIGHT AT GREAT HEIGHT

ZEPPELIN'S SUCCESS.

GERMANY'S TERMS: A BIG ADVANCE. (BY TELEGRAPH—PEESS ASSOCIATION—COPTEIBHX.) (Reo. July 3, 5.15 p.m.) Berne, July 2. Count Zeppelin's new; aerial warship,' No. 4, with a dozen * pass'eligers, made a twelve houra' flight, at a groat height from Lake Constance to Zurich and Lucerne and back. The, airship averaged SO miles an hour. HIGHER ELEVATION. AN AEEIAL WARSHIP'S RANGE OF ACTION. Count-Zeppolin works with dirigible balloons, and is tlieretoro in a school quite distinct from aeroplanists like the Wrights, Delagtatije, Farman, and others of the hcavier-than-air principle. Count Zeppelin had built three airships, with which his ontaincd much success, and the present craft, a larger machine, known 1 , as No. 4, is an attempt to go a great deal further and to fulfil the conditions of an offer made, by the Gorman Government. Germany agrees to take over two of the Zeppelin airships at a price of over 2,000,000 marks (JEIOO.OOO), if the Count, with his No. 4, makes an uninterrupted Bight of 24 hours', duration at a height greater than that hitherto attained, and if he demonstrates the ability of his apparatus to land- on terra firma at a given spot. Taking the terms of the offer seriatim—(l) Elevation: Tha words of the cablegram "at a great height," thongh not definite, would appear to indicate that this condition was complied witJi; (2) landing at a given spot: the journey to Lucerne and the return to Lake Constance should settle this point;'(3) duration: the balloon travelled for twelvo hours, or half the time stipulated in ' the German Govern, inent's. offer. Evidently the Count is well on tils road tewardn fulfilling the required conditions. Tho "fly" represents . another great advance in tho progress of dirigible balloons. Advices from Stuttgart dated February stated that Count Zeppelin : would shortly demonstrate "6ome further possibilities' of. his.system of rigid construction, viz: the power of l&nding on the ground, of attaining a height of, say, -4000 ft., and of making voyages extending ovor at least 24 hours. , The. arrangement of the pianos for raising and sinking the vessel has been. fairly well mastered, and the mode of steering in curves has likewise been devised.

. . . Tho vessel now being built Trill be somewhat larger than the old No. 3, and will hare engines of 250 h.p.. It is estimated that by this means the speed may be ineroased to 16.21 metres per second, saj 56km. per hour." A. speed of 58 kilometres is roughly 35 miles an hour. The cablegram states that the airship in this test averaged 30 miles. The same authority gives the following important information as to eleTation and range of action: "While tho steering apparatus is of the utmost importanoo at the time of landing, it is also of the highest value in guiding tho vessel upwards when great heights have to be attained. .Hitherto tho voyages have taken place at low elevations, where a cubic metro of air weighs 1.29 kg., while a oorrespoading volume of pure hydrogen weighs O.C9kg.; but when, tho airship attains a height' of 40fl0ft. above scAlevel the density of the atmosphere wiH be reduced to 1.095 kg. per cubic metro, and the lifting power of the hydrogen/ will fall, to 1.0085 kg. In these circumstances a largo vessel has groat advantages pvor a smaller one. ■: A. small airship weighing 2400 kg., Vith a. motor of 85 h.p., can only carry 500 kg. of benzine, whiob wonld suffice for a voyage of 20 houra. If this vessel had to . rise to a heigjit of 1200 metres; 300 kg. of benzine must be included for the sake of ballast to bo discharged later on> to lighten tho balloon.

"Bv this' means 'the range of action is reduced to a voyage of five hours, or a'diminution of 75 per' cent. The big airship, on tho other hand, weighing 10,000 kg., with a fuel provision for 100 hours, could keop at a.height of 1200 metres for about 36 hours, and ita range of action would bo reduced by 61 per cent. This does not, . however, randeir it cer-' tain that airship No. 3, in her present form, could carrv her full amount of fuel, and on reaching the required-height could enough ballast to remain'there for a'considerable length of time.. The'question.'of rang'o of action has likewise to be studied from other aspects. An airship which could maintain a speed of 50km. per flour for 50 hours would be out-distnncod by one capablo of travelling 40km. per hour for 100 hours. Their respective ranges would ,be in the proportion of five to eight. After all, the greater cost of building a large-sized vessel would be ; of no moment as compared with tho gain in efficiency,