264 



NA TURE 



[April 28, 1910 



(c) They disproved the " Newtonian law," that the 

 normal pressure varied as the square of the angle of 

 incidence on inclined planes. 



(d) They showed that the empirical formula of 

 Duchemin, proposed in 1836 and ignored for fifty years, 

 was approximately correct. 



(e) That the position of the centre of pressure varied 

 with the angle of inclination, and that on planes its move- 

 ments approximately followed the law formulated by 

 Joessel. 



(/) That oblong planes, presented with their longest 

 dimension to the line of motion, were more effective for 

 support than when presented with their narrower side. 



(i) That planes might be superposed without loss of sup- 

 porting power if spaced apart certain distances which varied 

 with the speed ; and 



(/») That thin planes consumed less power for support at 

 high speeds than at low speeds. 



The paradoxical result obtained by Langlev, that it takes 

 less power to support a plane at high speed than at low, 

 opens up enormous possibilities for the aerodrome of the 

 future. It results, as Chanute has pointed out, from the 

 fact that the higher the speed the less need be the angle 

 of inclination to sustain a given weight, and the less, there- 

 fore, the horizontal component of the air pressure. 



It is true only, however, of the plane itself, and not of 

 the struts and framework that go to make up the rest of 

 a flying machine. In order, therefore, to take full 

 advantage of Langley's law. those portions of the machine 

 that offer head resistance alone, without contributing any- 

 thing to the support of the machine in the air, should be 

 reduced to a minimum. 



Contributions to the Art of Aerodromics. 



After laying the foundations of a science of aerodromics 

 Langley proceeded to reduce his theories to practice. 

 Between 1891 and 1891; he built four aerodrome models, 

 one^ driven by carbonic acid gas and three by steam 

 engines. On May 6, 1896, his Aerodrome No. 5 was tried 

 upon the Potomac River, near Quantico. I was myself a 

 witness of this celebrated experiment, and secured photo- 

 ■ graphs of the machine in the air, which have been wide'y 

 published. This aerodrome carried a steam engine, and 

 has a spread of wing of from 12 to 14 feet. It was shot 

 into the air from the top of a house-boat anchored in a 

 quiet bay near Quantico. It made a beautiful flight of 

 about -;ooo feet, considerably more than half a mile. It 

 was indeed a most inspiring spectacle to see a steam engine 

 in the air flying with wings like a bird. The equilibrium 

 seemed to be perfect, although no man was on board to 

 control and ?uide the machine. 



I witnessed two flights of this aerodrome on the same 

 day, and came to the conclusion that the possibility of 

 aerial flight by heavier-than-air machines had been fully 

 demonstrated. The world took the same view, and the 

 progress of practical aerodromics was immensely stimulated 

 by the experiments. 



Langley afterwards constructed a number of other aero- 

 drome models, which were flown with equal success, and 

 he then felt that he had brought his researches to a con- 

 clusion, and desired to leave to others the task of bringing 

 the experiments to the man-carrying stage. 



Later, however, encouraged by the appreciation of the 

 War Department, which recognised in the Langley aero- 

 drome a possible new engine of w-ar, and stimulated by an 

 appropriation of 50,000 dollars, he constructed a full-sized 

 aerodrome to carry a man. Two attempts were made, 

 with Mr. Charles Manley on board as aviator, to shoot 

 the machine into the air from the top of a house-boat, 

 but on each occasion the machine caught on the launching 

 ways and^ was precipitated into the water. The public, 

 not knowing the nature of the defect which prevented the 

 aerodrome from taking the air, received the impression 

 that the machine itself was a failure and could not fly. 

 , This conclusion was not warranted by the facts ; and to 

 me, and to others who have examined the apparatus, it 

 seems to be a perfectly good flying machine, excellentlv 

 constructed, and the fruit of years of labour. It was 

 simply never launched into the air, and so has never had 

 the opportunity of showing what it could do. Who can 

 say what a third trial might have demonstrated? The 

 NO. 2 113, VOL. 83] 



general ridicule, however, with which the first two failures 

 were received prevented any further appropriation of money 

 to give it another trial. 



Conclusion. 



Langley never recovered from his disappointment. He 

 was humiliated by the ridicule with which his efforts had 

 been received, and had, shortly afterwards, a stroke of 

 paralysis. Within a few months a second stroke came, and 

 deprived him of life. He had some consolation, however, 

 at the end. Upon his death-bed he received the resolution 

 of the newly formed Aero Club of America, conveying the 

 sympathy of the members and their high appreciation of 

 his work. 



Langley's faith never wavered, but he never saw a man- 

 carrying aerodrome in the air. His greatest achievements 

 in practical aerodromics consisted in the successful con- 

 struction of power-driven models which actually flew. 

 With their construction he thought that he had finished 

 his work, and in 1901, in announcing the supposed con- 

 clusion of his labours, he said : — 



" I have brought to a close the portion of the work 

 which seemed to be specially mine — the demonstration of 

 the practicability of mechanical flight — and for the next 

 stage, which is the commercial and practical development 

 of the idea, it is probable that the world may look to 

 ethers." 



He was right, and the others have appeared. The aero- 

 drome has reached the commercial and practical stage, and 

 chief among those who are developing this field are the 

 Brothers Wilbur and Orville Wright. They are eminently 

 deserving of the highest honour from us for their great 

 achievements. 



I wish to express my admiration for their work, and 

 believe that they have justly merited the award of the 

 Langley medal by their magnificent demonstrations of 

 mechanical flight. 



INDUSTRIAL ENGLAND IN THE MIDDLE OF 

 THE EIGHTEENTH CENTURY. 



'T'HE conditions of the chief industries of the country at 

 the date (1754) when the Society of Arts was founded 

 were surveyed by Sir Henry Trueman Wood in an elaborate 

 paper read by him at a meeting of the society on April 20. 

 In the middle of the eighteenth century England was not 

 to any noteworthy extent a manufacturing country, the 

 most important, industry being agriculture and occupations 

 relating to it. At the epoch to which the paper refers, 

 however, an industrial revolution was beginning which 

 transformed England from an agricultural country, with 

 no manufactures beyond those required for the supply of 

 its own population, into the workshop of the world. Sir 

 H. T. Wood described the positions of industries con- 

 cerned with wool, cotton, linen, silk, various metals, 

 brewing, distilling, tanning, paper, printing, and many 

 other arts. From the mass of historical material brought 

 together in the paper a few extracts are subjoined upon 

 subjects associated with science. The retrospective view 

 which these extracts provide is of interest to students of 

 the progress of science and industry. 



Science. 



Science, about the middle of the eighteenth century, was 

 not in a condition of active progress either in England or 

 abroad. The time was not, either for science or scientific 

 men, a happy one. International intercourse was impeded 

 by wars ; national progress was hindered by political differ- 

 ences. The great daj's of Newton, Hooke, Boyle, and 

 Halley were past. Those of the founders of modern science 

 were yet to come. Cavendish had just left Peterhouse. 

 Priestley had not yet turned his attention to natural philo- 

 sophy — his scentific work began in 1758. Banks, who ruled 

 the Royal Society for so many years, was in 1754 a boy 

 of eleven. Gilbert White (b. 1720) commenced his 

 " Garden Kalendar " in 1751, but he did not make 

 Pennant's acquaintance until thirteen years later, when he 

 started the famous correspondence which formed the 

 groundwork of the immortal " Natural History of Sel- 

 borne." Franklin had completed and made public his 



