May 9, 1889] 



NATURE 



27 



Councils of our great Societies he was a man invaluable 

 for his intelligence, for his persevering energy, for his 

 promptness of resource, and for a generosity, princely, 

 but discriminating. These words will at once suggest 

 the regretted decease of Warren de la Rue. At the age 

 of seventy-four, he can hardly be said to have died full 

 of years ; but assuredly Warren de la Rue died full of 

 honours. He was almost, but happily not quite, the last 

 ■of a generation or two, of men who, possessing ample 

 pecuniary means in middle or early life, devoted the 

 means and the life to the search for truth in Nature, 

 each in his own line. The two Herschels, Wollaston, 

 Babbage, Gassiot, Spottiswoode, and De la Rue are gone, 

 and but few like to them still survive, linking us with 

 the past. " The old order changeth ; " and now the 

 endowed and professional student of Nature is fast 

 displacing the amateur. Nor need we altogether deplore 

 it ; for, after all, the Professor and the amateur belong to 

 the same race of Englishmen ; they have the same love 

 of the quest for truth ardent within them ; and in the 

 case of the Professor there is now superadded the spur 

 that comes from a sense of duty. 



Warren de la Rue was born in 1815, and was the son 

 of Mr. Thomas de la Rue, the founder of that eminent 

 firm of manufacturing stationers in Bunhill Row who have 

 rendered well-known services to social life by the produc- 

 tion of numerous articles, unsurpassed in excellence in 

 their particular craft. He first became known to the world 

 at large by his newly-invented machine for the manu- 

 facture of envelopes, which was placed in the Great 

 Exhibition of 1851, and formed one of the chief objects of 

 attraction there. Not far from it lay a small photograph 

 of the moon, taken by Bond with the Harvard refractor of 

 15 inches. It was comparatively, and from the circum- 

 stances of the times necessarily, but a poor performance, 

 yet it held out the promise of future possibilities, and it 

 certainly fired the hopes of De la Rue. It was to him 

 what the itinerant telescope in the streets of Bath became 

 to the elder Herschel, viz. the ^determining point of a future 

 and illustrious career. Accordingly, we soon find him 

 engaged in the construction of, what in the sequel has 

 become, his historic reflecting telescope, having an 

 aperture of 13 inches and a focal length of 10 feet. The 

 mirror was figured and polished by his own hands, and the 

 equatorial mounting of the telescope was completed in 

 his manufactory at Bunhill Row, from his own designs. 

 Here again our thoughts revert to the elder Herschel ; but 

 that great astronomer never approached the perfection 

 either of the De la Rue mirror, or of the mechanism 

 by which it was mounted and by which it was moved. 

 It is, however, only just to say that much of this notable 

 improvement was the natural outcome of the lapse of time 

 and of the progress that had been made in the working of 

 metal. The instrument was mounted in the suburbs of 

 London, at Canonbury, in a small garden surrounded by 

 houses. It was hither, when the day's work was done at 

 Bunhill Row, that De la Rue r etired at night ; and here, by 

 patiently waiting for a clear and serene atmosphere, an 

 event of rare occurrence, and then only during the small 

 hours of the morning, he finally succeeded in taking 

 telescopic pictures of the planets Jupiter and Saturn^ 

 which it may not be too much to say remain still the 

 equals of any subsequent delineations of the same planets. 



Of the Saturn picture, John Herschel was heard to say 

 that he could die content if he could but once see the 

 planet itself as beautifully defined. This great success 

 at once placed him among the chief amateur practical 

 astronomers of the day. . 



It was about this time that he associated himself with 

 Owen, Quekett, Bowerbank, and others, in the formation 

 of the Microscopical Society ; and such were the keenness 

 and exactness of his eyes and hand, that he soon became 

 a chief referee for the performance of the wonderful 

 microscopic objectives which then for the first time were 

 produced by the skill of Powell and Andrew Ross. 



His first essays in lunar photography were not so suc- 

 cessful as he had anticipated : the collodion plates were 

 deficient in rapidity, and his telescope, not being as yet 

 provided with a clock movement, he was unable to keep 

 the moon motionless in the field, even for the short ex- 

 posure requisite to secure a photographic image. All this, 

 however, was soon rectified. For, about the year 1857, 

 he removed his residence and his telescope from Canon- 

 bury to Cranford, a village distant from London by some 

 twelve miles west. There he provided his instrument' 

 with an admirable driving clock, and applied what leisure 

 he could get, sedulously to celestial photography ; and 

 there he secured the earliest substantial results of a 

 method, which, at present, bids fair to revolutionize the 

 processes of the most exact and refined astronomy. The 

 photographs of the moon which he now obtained still re- 

 main works of art, which even the most skilful of recent 

 astronomers find it difficult to emulate with success. He 

 also made many attempts to photograph the solar disk ; 

 but owing to mechanical difficulties, connected with the 

 necessarily infinitesimal duration of the exposure of the 

 plates, his success was not great. He had hoped that, 

 by treating the photographs stereoscopically, he might 

 decide the true nature of sun-spots in respect of their 

 being depressions or the reverse ; but, although the evi- 

 dence seemed greatly in favour of depression, the ques- 

 tion can hardly be considered as photographically 

 settled. His efforts in this direction ended in the 

 construction of a small telescope for the Royal 

 Society, with an object-glass of 3.^ inches aperture 

 properly corrected ; and, with this photo-heliograph, 

 numberless pictures of the sun were successfully taken 

 at the Kew Observatory. This instrument has proved 

 the parent of many others established in various parts 

 of the world, so that at present scarcely a day passes 

 without a record of the condition of the sun's disk. 

 The arrangements for these observations of sun-spots are 

 now constituted under the advice of the Solar Committee 

 at South Kensington, and in due time no doubt important 

 facts will be brought to light. All this is traceable to 

 the little inconspicuous photograph deposited not far 

 from the envelope machine in 1851 ; and in this way De 

 la Rue became, and will ever be remembered as, the 

 Father of Lunar and Solar Photography. 



In i860, De la Rue took this photo-heliograph with him 

 on board the Himalaya, in connection with the memor- 

 able expedition to the Spanish Pyrenees, for the purpose 

 of observing the total eclipse of the sun. He posted 

 himself, with his whole battery of implements, at Riva 

 Bellosa, in the valley of the Ebro, not far from Vittoria. 

 He was successful in obtaining several photographs o{ 



