420 



NA TURE 



[March 5, 1908 



•deatlis piT million tons of coal that the United States not 

 only occupies a position worse than that of European 

 countries, but also exhibits a general increase in the rate, 

 whereas every other country has shown a decrease. The 

 situation is still worse when it is considered that the natural 

 conditions in America for raising coal with the minimum 

 amount of danger to the workmen employed are as 

 favourable as in any other country in the world. The 

 natural result of the working of the thinner and less 

 favourably mined seams will be greatly to increase the 

 death-rate unless regulations based on careful investigations 

 iire rigidly enforced, 



Egypt furnishes a region of great scientific interest 

 which is as yet almost unexplored in many branches of 

 knowledge, and it often happens that observations which 

 seem commonplace to those resident in the country are of 

 great value to workers elsewhere. The success which 

 attended the periodical Survey Notes during the fifteen 

 months it has been in existence has suggested that its 

 scope might be extended with advantage, and with that 

 object it has been decided to include communications on 

 all branches of science. The magazine, which will in 

 future be entitled the Cairo Scientific Journal, makes, in 

 its January issue, a good start. The principal contents 

 are papers on an expedition to .\ddis .\bbaba, by Mr. J. I. 

 Craig ; on the underground waters of Egypt, by Mr. 

 H. W. Beckett ; on the use of the slide-rule in surveying, 

 by Dr. J. Ball ; on azimuth checks on traverse work, by 

 Mr. M. Villiers Stuart; on upper air research at Helwan, 

 by Mr. B. F. E. Keeling ; and on temperature and con- 

 structional stability, by -Mr. J. I. Craig. 



On February i« Mr. J. J. Prost read before the Institu- 

 tion of Civil Engineers a paper describing a remarkable 

 .achievement in mining engineering, the shaft sinking at 

 the Horden colliery, south-east Durham. The work was 

 of exceptional difficulty owing to the large volumes of 

 water encountered in sinking through the magnesian lime- 

 stone and sands of Permian age. In view of possible 

 legislative interference with the hours of underground 

 labour, it was decided to sink three shafts, two 20 feet 

 and one 17 feet in finished diameter. The north shaft 

 was begun on November 6, 1900, and was finished at a 

 depth of 419 yards on July 23, 1904. The south shaft was 

 begun on February 28, 1901, and was finished at a depth 

 of 302 yards on September i, 1905. The east shaft, 17 feet 

 in diameter, was begun on September 3, 1900, and was 

 finished at a depth of 406 yards on November 6, 1905. 

 The maximum feeders of water pumped simultaneously at 

 any one period amounted to 9230 gallons per minute, from 

 the east and south shafts, from September 23 to November 

 26, 1903. The production of coal from this colliery is 

 now averaging a million tons per annum. 



The annual report of the council of the Institution of 

 Mechanical Engineers, presented at the annual meeting of 

 members on February 21, summarises the progress and 

 work of the institution during the past year. The council 

 has accepted from Mr. Charles Hawksley an offer of 

 1000/. for the foundation of a scholarship or premium in 

 connection with the institution, to commemorate the 

 centenary of the birth of his father, Mr. Thomas Hawksley, 

 past-president. In connection with the alloys research 

 committee it is noted that sea-water corrosion tests on 

 copper-aluminium alloys are being carried out at Ports- 

 mouth Dockyard by the National Physical Laboratory. 

 A systematic investigation of the ternary alloys of copper 

 and aluminium with other metals, in the first place with 



NO. 200 !, VOL. yy] 



manganese, zinc, and nickel, has been begun, and the pre- 

 liminary investigation of the copper-aluminium manganese 

 alloys is approaching completion. The council has made 

 a small grant to Dr. H. C. H. Carpenter to investigate 

 at the Manchester University the conditions which have to 

 be observed if metal castings are to be capable of being 

 gas-tight and steam-tight. Some further experiments on 

 the large gas engine at the University of Birmingham 

 are to be carried out by Prof. F. W. Burstall with a 

 water-brake and with both optical and string indicators. 

 The research committee on the value of the steam-jacket 

 has met twice during the year, and designs are being 

 prepared by Prof. T. Hudson Beare for carrying out 

 jacket experiments with a larger apparatus than that 

 formerly used by the committee. Information on the 

 present state of Icnowledge on the following subjects is 

 also being collected, previous to the appointment of re- 

 search committees for prosecuting further inquiries : — 

 (i) the features of refrigerating machinery in which further 

 investigation is needed ; (2) the transfer of heat across 

 metallic surfaces in contact with water and with gases ; 

 (3) the action of steam passing through nozzles and stejun 

 turbines. 



The Physikalisclic Zeitschrift for February 15 contains 

 an account of Dr. H. W. Schmidt's experiments on the 

 effect of high temperatures on the disintegration of 

 radium C The work was undertaken to decide between 

 the conclusion of Messrs. Makower and Russ, that high 

 temperature diminished temporarily the activity of radium, 

 and that of Mr. Bronson, who denied the existence of 

 such an efifect. Dr. Schmidt's experiments were made 

 on radium C prepared by von Lerch's method. The pre- 

 paration was enclosed in a quartz tube which could be 

 heated to 1300° C. in an electric furnace. The activity 

 was measured by the fall of the leaves of a gold-leaf 

 electroscope placed close to the furnace. The author con- 

 cludes that at 1300° C. the preparation behaves exactly as 

 :il ordinary temperatures. 



The theory of the radiation of the -\u(r incandescent 

 gas mantle is discussed b\- M. M. Foix in the February 

 number of the Journal dc Physique. It is generally 

 admitted that the mantle owes its brilliance to its selective 

 radiation, which appears, according to the researches of 

 Prof. Rubens, to bo brought about by the addition of a 

 little oxide of cerium to oxide of thorium. M. Foi.x now 

 comes to the conclusion that the luminous efficiency of the 

 mantle can be increased by carrying the dilution of the 

 oxide of cerium in the oxide of thorium a further stage, 

 the result being brought about by the diminution of the 

 infra-red radiation of the mantle and a consequent increase 

 of its temperature. The best proportion of the oxides 

 appears to be i of cerium to 100 of thorium. 



The attention of those of our readers who practise 

 photography is directed to the catalogue of photographic 

 dry plates, filters, and safelight screens recently issued 

 by Messrs. \\"ratten and Wainwright, Ltd., of Croydon. 

 The particulars provided are practical in character, and 

 the tables of sizes and prices conveniently arranged. 



The March issue of the yational Review opens a new 

 series, printed in larger type and provided with a different 

 cover. Among its varied contents we notice an apprecia- 

 tion of the late Lord Kelvin by Sir \\'illiam Ramsay, 

 K.C.B., F.R.S., in which a delightful picture of Kelvin 

 as a teacher is drawn, and a popular account given of 

 some of his contributions to natural knowledge. 



