March 24, 1898] 



NATURE 



485 



course of this old river-valley over the platform the channel has, 

 to a great extent, been choked up and nearly obliterated by the 

 deposit of sediment constantly going on for long ages ; but along 

 this part of its course, owing doubtless to the force of the tidal 

 currents due to the narrowness of the channel, the sediment has 

 apparently not been able to accumulate ; hence the well-defined 

 banks of rock which the soundings disclose. As regards the 

 submerged channels of the existing rivers entering the Atlantic 

 westwards, only faint indications can be obtained from the sound- 

 ings ; nor is this surprising when we recollect that the North 

 Sea, the Irish Channel, and portions of the ocean bordering the 

 northwestern coasts of the British Isles have been covered in 

 part by land ice, and altogether by the muddy waters of the 

 later glacial seas, giving place to those of the present day ; the 

 mud, sand and shingle thus deposited have sufficed to cover the 

 old floor of the platform for many feet in depth in most places, 

 and to fill up the channels of the streams formed during earlier 

 emergence. The total distance from north to south through 

 which these observations extend is about 500 miles. I hope to 

 be able to return to the subject later on. Edward Hull. 



The Use of Compressed Coal Gas. 



It may be of interest to users of the limelight to put on record 

 the following occurrences. 



A 40- feet cylinder was filled with coal gas at a pressure of 

 120 atmospheres by a leading London firm on March 15, 1897 '■> 

 a small quantity was used, and the cylinder stood till October 

 9. It was then used for a mixed jet, and at the end of half an 

 hour the light began to decrease, and in another quarter of an 

 hour practically no gases were issuing. On relighting the jet 

 the light was found perfect, and the fault was ascribed to the 

 Beard's regulator. 



The cylinder was again used on March 5 last, and again after 

 half an hour the light began to fail ; but on turning the taps 

 full on something audibly blew out of the nozzle, and the light 

 was perfectly restored. 



The lime blackened excessively: while white-hot, the "hydro- 

 gen " was turned oflTand the oxygen allowed to play on it, when 

 the deposit turned a brilliant orange-red. 



The coal gas was then passed through a glass tube gently 

 heated in a Bunsen flame— a copious metallic mirror which gave 

 the test for iron was formed. 



It seems probable that the jet was choked by the decomposi- 

 tion of iron catbonyl at the high temperature. In any case 

 there is an obvious disadvantage in storing for a considerable 

 time compressed coal gas in steel cylinders, altogether apart 

 from the possible damage to the cylinders, which has been 

 shown to be small. C. E. Ashford. 



Harrow, March 19. 



THE SCIENCE BUILDINGS AT SOUTH 

 KENSINGTON. 



SINCE the nation acquired, a good many years ago 

 now, a plot of ground from the Royal Commis- 

 sioners of the Exhibition of 185 1, at a cheap rate, on 

 which to erect buildings to foster teaching and research 

 in Science and Art, there have been many schemes put 

 forward, but nothing done, till at last the teaching of 

 Science has become desperate. The Government have 

 known this fully, and a few years ago plans were designed 

 to bring to a head the various schemes by erecting 

 Science buildings on the west side of Exhibition Road, 

 and the Art buildings on the east side, an allocation of 

 the spare land which had been accepted in principle by 

 everybody. 



But now it appears there has been a sudden volte face. 

 Seeing that at the present moment Art does not require 

 all the space at its disposal on the east side, the inter- 

 stices are to be filled up with certain of the science 

 buildings as we gather from the statement made by 

 the First Commissioner of Works, on Thursday last : 

 " The Government asked for the large sum of 800,000/. 

 for the completion of the buildings at South Kensington 

 in connection with Science and Art. He was quite certain 

 that the Committee would admit that the settlement of 

 this question had been demanded both by the House and 

 by the public for many years past. In 1891 the decision 



NO. 1482, VOL. 57] 



was come to to proceed with the building to com- 

 plete the accommodation for the Art Museum, and 

 for housing the administrative departments of Science 

 and Art. Plans were accordingly prepared by Mr. 

 Aston Webb, and accepted, for a building to occupy the 

 land on the south side of the Museum facing the Crom- 

 well Road ; but the sources at the disposal of Chancellors 

 of the Exchequer, on both sides of the House, unfor- 

 tunately did not permit of the grant of the necessary 

 funds, and the scheme had since then been in abeyance. 

 Since that scheme was formulated, and partly in con- 

 sequence of the report of the Commission on Secondary 

 Education, it was in contemplation to move to the Edu- 

 cation Office the secretariat of the Science and Art 

 Department, and further — in accordance with the re- 

 commendation of the Select Committee of last year on 

 the South Kensington Museum— it was decided to re- 

 move the official residences and certain other temporary 

 buildings, which were a source of danger from fire. 

 With this additional space at disposal, it would now be 

 possible to provide on the eastern side of Exhibition 

 Road the necessary accommodation for both Science and 

 Art. It was, therefore, intended to build, in addition to 

 the building proposed in 1891, further buildings which 

 would complete the frontage on the Cromwell Road and 

 Exhibition Road sites ; and, in the opinion of the 

 Government, that would amply meet the requirements 

 of both branches for many years to come." 



On this proposal the Times remarks : — 



" How far these projects, which the Government regard 

 as all that can be reasonably demanded, will be satis- 

 factory to those who take more than an official interest 

 in the matter it would be premature to speculate." 



We do not think it " premature " to state that it is to 

 be hoped that the Government before they go further 

 in this matter will obtain some opinions from men of 

 science. The suggestion appears little short of disastrous, 

 having regard for the future representation of scientific 

 teaching and illustrations in our National Institutions, 

 for surely the Empire will outlast another century. These 

 remarks are not made because the sum asked is too little, 

 for we do not believe a: Committee, say of the Royal 

 Society, or the President and Council of the Society 

 itself, appointed to consider the matter, would see its way 

 to spend more than 250,000/. to cope with the present 

 needs of Science. 



SKIAGRAPHY AFTER INJECTION OF THE 

 BLOOD VESSELS WITH MERCURY, 



TO elucidate the relation^ of the various opaque struc- 

 tures of the body to one another whilst undisturbed 

 by the processes of dissection, is one of the numerous 

 uses to which skiagraphy has been applied. 



It is obvious that this process may be extended to the 

 blood vessels in the dead body by filling them with some 

 medium which is opaque to the X-rays, and in this way 

 their relative situations to each other and to the bony 

 skeleton may be studied with facility. Various ex- 

 perimenters have occupied themselves with the task of 

 producing such skiagraphs, and amongst a considerable 

 number who have obtained successful pictures may be 

 mentioned Dutto, Raw, and Remy and Contremoulins, 

 the former of whom employed a plaster injection mass, 

 the latter one of wax in which bronze powder was 

 suspended. 



These results, though sufficiently encouraging, were 

 not wholly satisfactory, and one of us (H. J. S.) deter- 

 mined to follow out a method which he had devised 

 before he became acquainted with the work of other 

 observers, and in which metallic mercury had been 

 selected as the substance to be injected. The results of 

 our experiments with it have been most satisfactory, and 

 it seems probable that with the greater experience which 

 we have now gained in the methods of carrying out the 



