26 



KNOWLEDGE & SCIENTIFIC NEWS. 



[Feb., 1905. 



one to our apprehension super-eminent over the rest; 

 they are separated by vast, apparently clear intervals; 

 they are non-nebulous, and of stable constitution. This 

 secure habitat is ours for the present; it may, neverthe- 

 less, at some future time be exchanged for one less 

 exempt from disturbance. The shape and size of the 

 sun's orbit are utterly unknown ; the changes of en- 

 vironment, accordingly, that will accompany the 

 description of it defy conjecture. Our actual course is 

 inclined at a small angle to the plane of the Milkv Way. 

 It will presumably become deflected; but perhaps not 

 sufficiently to keep our system clear of entanglement 

 with the galactic star-throngs. In our ignorance of 

 their composition, no forecast of the results can be at- 

 tempted; they are uncertain and exorbitantly remote. 

 Moreover, the comparative slowness of the sun's motion 

 in a manner guarantees the permanence of his sub- 

 sisting cosmical relations. For anything that science 

 can tell, they may ultimately be subverted by some pre- 

 ordained catastrophe; but the possibility lies outside the 

 field of legitimate speculation. 



The universe, as reflected in the mind of man, gains 

 extent as the mirror acquires polish. Early astrono- 

 mers conceived of but one solar system, and one "daedal 

 earth," upon which the " pale populace of heaven " 

 rained influences sinister or propitious. Later, human 

 egotism took another form. The whole universe was 

 assimilated to our particular little settlement in it. 

 Terrestrial conditions were universalised. None diver- 

 gent from them were counted admissible or profitable. 

 But one answer seemed possible to the perpetual Cui 

 bono? with which restless thought assailed the heavens. 

 But one purpose was regarded as worthy of fulfilment; 

 that of multiplying, in distant sidereal climes, copies 

 of our own planet, and of providing suitable locations 

 for myriads of intellectual beings, as little alien to our- 

 selves as might be compatible with the minimum of 

 diversity in their material surroundings. 



The spread of this astral philanthropy has, neverthe- 

 less, been in some measure checked by the advance of 

 knowledge. Our position and circumstances have been 

 shown by it to be, if not quite peculiar, at any rate very 

 far from inevitable. It has reduced by a process of ex- 

 clusions to a relatively limited number the class of 

 stars that can fairly be regarded as possible centres of 

 vitality; it has immensely widened the scope of dis- 

 cernible variety in cosmical arrangements, and held out 

 warnings against errors of interpretation due to con- 

 genital prepossessions. And we shall surely not 

 wander from the truth by recognising our inability to 

 penetrate all the depths and intricacies of Infinite De- 

 sign. 



To Prevent the Stripping of 

 Photographic Films. 



I\ warm climates it is often most difTirult to prevent the 

 gelatine film from becoming detached from a plate 

 during development, and the usual methods, such as 

 adding a little alcohol to the developer are not sufficient. 

 Other methods are objectionable on account of their 

 effect on the development or fixing. M. Mercier has 

 lately tried, with good effects, tannin the gelatine. A 

 bath is made up of the following :— Alcohol (90°) 

 250 cc, tannin 60 gr., water 500 cc. The plates are 

 immersed for two or three minutes in this bath, after 

 which they are carefully washed before being placed in 

 the developer. The final washing must be continued 

 until all traces of tannin have disappeared. 



Progress ^vith Airships 

 in 1904. 



By Major B. Baden-Powell. 



XoTWiTiiSTANDiNC. thc \cry tempting bait of a prize of 

 ;^"2o,ooo for an airship capable of attaining certain 

 speeds over a fixed course, the competition in connec- 

 tion with the World's Fair at St. Louis can hardly be 

 characterized as a success. Not only was there a lack 

 of machines specially built with the object of carrying 

 off this prize, but there was even a noticeable absence 

 of those in existence which might have been able to 

 comply with the conditions. M. Santos Duinont, for 

 some reason not yet clearly explained, withdrew after 

 taking his powerful new airship across the Atlantic. 

 MM. Lebaudy do not seem to have had any intention 

 of submitting for trial their most successful machine, 

 nor did M. Deutsch send over more than a model of his 

 " Ville de Paris." But what is even more unaccount- 

 able is that American inventors, such as the Messrs. 

 Wright and Prof. Langley, were conspicuous by their 

 absence, and did not enter their flying machines even 

 for show. The rumours we have heard of Mr. J. P. 

 Holland, of submarine-boat fame, and Prof. Graham 

 Bell, the inventor of thc telephone, having respectively 

 devised new apparatus to navigate the air, have re- 

 ceived no corroboration from St. Louis. 



However, it cannot be said that there were no air- 

 ships at thc Fair. Three of them were open to inspec- 

 tion in the huge sheds specially constructed for housing 

 the competing vessels. Two of them actually made 

 ascents, and with some success. Unfortunately, the 

 most promising of the three, that of M. Francois, could 

 not even be inflated with gas. This apparatus consists 

 of an elongated bailf)on ol 1,150 cubic metres, support- 

 ing a wooden car containing a 25-28 h.p. Lambert 

 water-cooled petrol engine (weighing 270 Uis.), which 

 rotates two pairs of screw propellers. There are two 

 horizontal shafts, one on each side of the car. Each of 

 these has a propeller mounted on each end of it. The 

 fore screws (about 9 ft. diameter) are smaller than 

 those in rear (12 ft.), the idea being that the larger 

 after screw will be alile to effect a bigger column of air 

 without, presumably, ha\ing so much work to do as if 

 the smaller screw had not already acted on an inner 

 column of air. The reasoning of this may not seem to 

 be quite sound, but practical trials alone could prove if 

 there was anything in it, and we can but watch for 

 results. 



Mr. Baldwin, whose name was much before the 

 English public some 15 years ago on account of his 

 bold and sensational parachute descents, exhibited an 

 apparatus of the Santos Dumont type. As may be 

 seen from the photograph, the elongated balloon sup- 

 ported a long trussed-girder beam, towards the fore- 

 end of which was a two-cylinder petrol engine of 5 h.p. 

 (almost hidden, in the photograph, by the figure of Mr. 

 Baldwin). A tractor screw was placed at the fore-end. 

 This was 10 ft. in diameter, the blades being each 

 3 ft. 4 ins. long by 2 ft. 2 ins. wide. A large rudder 

 was placed behind, moved by tiller lines. This machine 

 made its first ascent on October 25, piloted bv Mr. 

 Knabenschue. There was a light wind blowing, about 

 six to eight miles per hour, but this proved altogether 

 too strong for the airship, which made several turns 

 around, but failed to stem the breeze, and was carried 

 away over the town of .St. Louis. Some days after- 



