352 



NA TURE 



[August 13, 1891 



instruction is also being arranged (estimated tj cost ;i^500 per 

 annum), but the details have not yet been finally settled. 



The managers of the New Gallery announce a "Victorian 

 Exhibition," covering the fifty years of Her Majesty's reign from 

 1837 to 1887. As in the case of the preceding exhibitions, it 

 will contain pictures and other records of events illustrating the 

 history of the Royal Family and of the nation ; and it will con- 

 tain, above all, a series of portraits of the illustrious men and 

 women who, in so many different ways, have made their mark 

 upon the age. We gather from an article in the Times that 

 science, in this of all reigns, is not likely to fall behind. We 

 are promised pictures of Charles Darwin, Faraday, and Sir John 

 Herschel, of Lyell and Murchison, of the two Stephensons, of 

 Fox Talbot, one of the inventors of photography, and of Wheat- 

 stone, one of the inventors of the telegraph. The article adds 

 that "it would be easy to quadruple this list, supposing the 

 eminent men of science to have had the time and the vanity to 

 sit for their portraits," We agree. 



The Pall Mall returns to the charge on the subject of the 

 imagined unpopularity of the British Museum, and states that 

 although the evening openings have so far been a failure, and a 

 vei-y costly failure, the first installation of the electric light cost- 

 ing over £\.'j,ooo, the problem is being carefully considered. 

 It is also stated that it is an open secret that for some years past 

 the Trustees have been unanimous in favour of Sunday opening, 

 which, as they have more than once pointed out, would entail 

 little or no extra work on the officials, but merely change of 

 w irk for a few policemen. Among the things that are wanted 

 are certainly continuity in the hours during which the Museum 

 is open on any one day, and the possibility of obtaining some 

 decent refreshment. If in these matters the Trustees will imitate 

 he arrangements at the South Kensington Museum, we believe 

 the attendance will be increased — the attendance of workers 

 certainly will. 



We are requested to state that the designs submitted in com- 

 petition for the completion of the buildings of the South Ken- 

 sington Museum are now on view at that Museum from lo till 6. 



During the whole month of July little variation in the state 

 of Vesuvius was observable ; the lava flowed steadily on, 

 and had at one time extended down the Fossa della Vetrana, 

 nearly opposite the lodge and gate of Messrs. Cook's private 

 road to the Vesuvian railway, but immediately cooled, and 

 again started flowing much nearer its source. At the 

 .summit of Vesuvius the vapour appeared to issue almost 

 as in the normal state of the mountain, except for mo- 

 mentary interruptions and occasional ejection of dust and 

 sand. Dr. Johnston-Lavis, who has recently visited the 

 scene, sends us the following details: — "On July 30, I again 

 visited the top of the great cone. The central crater has con- 

 siderably enlarged, and has now an elliptical plan, with the major 

 axis directed north-west to south-east, but this form has been de- 

 rived from its original circular shape by the greater destruction 

 of the lips towards the south-east. The edges were in a most 

 unstable state, and attempts at photographing the interior were 

 accompanied by considerable danger, and required many pre- 

 cautions. On the inner walls I was, however, able to make out 

 several dykes besides the hollow one that has supplied the great 

 eastern rift for its several eruptions from 1881-82 to 1890. These 

 may be enumerated as directed north-east ; north-north-west, 

 probably the dyke formed at the commencement of this eruption ; 

 north-west ; south-west, probably the cooled upper extremity of 

 the lava sheet filling the south-west fissure which I have so often 

 mentioned ; and lastly, the hollow dyke to the soath-south-east, 

 which supplied the lava of May 1885, is again exposed. There 

 may be other dykes, but the large amount of vapour filling the 

 crater, and the danger anl impossibility of approaching the 



NO. 1 1 37, VOL. 44] 



edges in most parts, prevent a very detailed examination. So 

 far as I could make out, the situation of the vent is quite to the 

 south-east of the crater bottom, so that this fact, combined with 

 the prolongation of the crater in that direction and the existence 

 of numerous radial fissures, would indicate that the general 

 tendency is for the next lateral disruption to take place towards 

 Pompeii, or Torre Anunziata. On July 30 the lava was flowing 

 very slowly just at the junction of the Atrio del Cavallo and the 

 Fossa Vetrana. To an experienced observer the whole state of 

 the mountain is still very unstable, and a fresh outburst might 

 occur at any moment, although the volcano may gradually quiet 

 down. But a few days before my visit, four strong earthquakes 

 were felt at the lower railway station, showing that important 

 fra;turing, injection, or other dynamic disturbances were taking 

 place in the great cone." 



We have received from Mr. C. Mostyn an interesting letter 

 on the well-known appearance of the green ray at sunrise or 

 sunset caused by the refraction of the air. He states : — " This 

 'green ray' is seen to best advantage at ^xmrise, owing I 

 imagine to the eye not being wearied with watching the previous 

 glare, as is apt to be the case at sunset. At the same time, I had 

 many very satisfactory observations at sunset, one in particular, 

 when we were running before a very heavy sea in the Southern 

 Ocean, and the ' green ray ' was seen no less than three times in 

 as many seconds, as the ship rose and fell on the huge waves 

 causing as it were two sunsets, with a sunrise between them. 

 The best displays took place when the refraction near the horizon 

 was of such a character that the sun assumed a balloon, or vase, 

 shape as he came close to the sea-line. When, on the contrary, 

 the sun appeared flattened out in its horizontal diameter, the 

 ' green ray ' was either entirely absent, or was seen only in an 

 indistinct and uncertain manner." 



• Sir Edward Watkin having now, we presume, cured un- 

 punctuality on the many lines of railway which he is highly paid 

 to manage, is again turning his attention to Snowdon. It will 

 be remembered that he proposed in the first instance to erect an 

 astronomical observatory there. This, of course, was ridiculous. 

 We are now told that the authorities of the Trinity House have 

 expressed warm approval of his more recent proposal to place 

 an electric light on the summit. The Elder Brethren consider 

 that the light should prove an invaluable addition to those 

 already erected round the North Wales coast for the guidance of 

 mariners. Sir Edward hopes to have the light burning before 

 Christmas. 



The Directors of the Crystal Palace, in deference to the wish 

 of the Electrical Trade Section of the London Chamber of 

 Commerce, have decided to postpone the opening of the Elec- 

 trical Exhibition from November 1891 till January i, 1892, on 

 which date the Exhibition will be formally opened. 



We learn from the Photographic News that the great progress 

 that has been m.ade in the methods by which rapid movements 

 can be analyzed is well seen in a series of photographs lately 

 taken by Anschiitz, of Lissa, who has already given to the 

 world some of the best instantaneous pictures ever taken. Tne 

 subject of the pictures at present under consideration is a dog 

 jumping over a small bush. In the act of making one jump the 

 animal has been photographed twenty-four separate times, and 

 each picture is not a mere silhouette, as was the case with 

 Muybridge's first attempts of this kind, but a little picture show- 

 ing half-tone and detail. Some of the attitudes are, of course, 

 comic in appearance, for they represent phases of a movement 

 which the eye is unaccustomed to, and cannot possibly appreciate. 

 Notably is this the ca'^e in the commencement of the jump, 

 when the dog's hind toes only touch the ground ; and again at 

 the finish of the jump, when his legs are gathered together in a 

 heap. 



