April 7, 192 1] 



NATURE 



181 



to be highly favoured in general climate. The space 

 given to the article is necessarily too limited for great 

 ■detail. 



The December issue of Terrestrial Magnetism and 

 Atmospheric Electricity contains the preliminary 

 results of the magnetic survey of the Indian and 

 Southern Oceans carried out by the United States 

 survey ship Carnegie during the summer and autumn 

 •of last year. The values obtained for the deviation 

 of the compass over the south-easterly course traversed 

 from Colombo to a point about io° west of the Straits 

 of Sunda differ little from those given in Admiralty 

 Charts 3776 and 3777 for 1917, but over a considerable 

 area of the Indian Ocean directly south of Ceylon, 

 between latitudes 25° and 35° S., the westerly devia- 

 tions are a degree or more greater than those given 

 in the charts. From this region to Fremantle, and 

 ihence to a region in latitude 50° S. directly south of 



■ South Australia and Victoria, the new observations 

 agree with the charts, but in the latter area the 

 easterly deviations given in the charts are about 1° too 

 small. For the rest of the course to New Zealand 

 the observations agree fairly well with previous 

 records. 



In an address to the students of Faraday House on 

 February 25 Sir Philip Dawson discussed the possi- 

 bilities of electric traction in connectioH with heavy 

 railway work. He considered that many railway en- 

 gineers laid too much stress on standardisation, and 



■ this was preventing progress. Great harm can be 

 done by excessive standardisation. The solution ad- 

 visable for one line of railway might be quite unsuit- 

 able for another. He thought that the French 



I Government had made a mistake in standardising 

 : 1500 volts direct current for electric traction. Ger- 

 many, Sweden, and Switzerland had adopted 16,000 

 volts alternating current as the standard pressure. 

 » The United States has not yet introduced any legisla- 



■ tion, and side-by-side extensions are going on of 

 3000-volt direct-current systems and 11,000-volt single- 

 phase alternating systems. Few realised the amount 

 of power required for electric traction, e.g. a train 

 going out of Victoria Station took 2000 kw. (2680 

 h.p.), and Sir Philip calculated that of the total 

 demand for electricity in the London area contem- 

 plated by the Electricity Commissioners about half 

 would be required for the railways. When the 

 suburban electrification of the Brighton system was 

 completed it alone would require 50,000 kw. There 

 had been practically no interference with telegraph 

 iand telephone circuits by the large currents used on 

 .this railway. 



An illustrated account of the new works at Canning 

 Town belonging to the British Glass Industries, Ltd., 

 appears in the Engineer for February 25. These 

 works are already in partial operation, and are de- 

 signed to be the largest glassworks in Great Britain. 

 The plant will consist of nine units, each complete in 

 itself as a glass factory, and the total output of bottles 

 lor jars when the works are in full operation will be 

 approximately 600,000 a day. To obtain this output 

 continuous shifts will be employed. The plant is 

 being laid out in conformity with modern practice, 

 NO. 2684, VOL. 107] 



including mechanical mixing and the latest types of 

 melting furnaces and gas-producer and annealing 

 plants. Pyrometric control of temperature is em- 

 ployed in both the melting and annealing furnaces. It 

 is claimed that there is only one fully automatic bottle- 

 making machine in existence — the Owens — all the 

 others requiring the addition of a separate device for 

 feeding the glass into the machine. The type in- 

 stalled at the Canning Town works is the Dauben- 

 speck, which is designed for making wide-mouthed 

 bottles; this machine is made by Messrs. Fraser and 

 Chalmers, of Erith. 



An illustrated account of a new type of crankless 

 steam engine appears in Engineering for March 11. 

 This engine has been constructed to the designs of 

 Mr, A. G. M. Michell, the inventor of the Michell 

 thrust-block. The engine is enclosed in a cylindrical 

 casing, and the rotating shaft is co-axial with the 

 casing. At the centre of the shaft is a swash-plate, 

 i.e. a plate with its plane inclined to the shaft axis, 

 62-5° in the experimental engine, but to be made 67-5° 

 in future. There are eight cylinders, four on each 

 side of the swash-plate arranged round the shaft with 

 their axes parallel to the shaft axis. Opposing pistons 

 are connected together by a bar crossing the outside 

 of the swash-plate. Each of the eight pistons bears 

 against the side of the swash-plate through a Michell 

 thrust-pad. The engine is uniflow, i.e. steam acts on 

 one side of the pistons only, and steam is admitted to 

 the cylinders by means of two rotating disc valves, 

 one at each end of the casing, and exhaust at the 

 end of the outer stroke takes place through ports un- 

 covered by the pistons. The design lends itself to 

 very perfect balancing, and tests show that the de- 

 signed speed of 1200 r.p.m. can be greatly exceeded. 

 The cylinders are each 5 in. in diameter, and 092 in- 

 dicated h.p. per cylinder per 100 r.p.m. has been 

 obtained. The success of this experimental engine 

 is due to the Michell pads, for which the coefficient 

 of friction is of the order 0002. 



Owing to the shortage of edible fats in Germany 

 during the war, attempts were made to produce fatty 

 acids from natural hydrocarbons of the paraffin type 

 which were obtained by the distillation of lignite. 

 The progress made is reviewed in the Chemical Trade 

 Journal for December 4 last and in the Journal of the 

 Society of Chemical Industry for February 28. Many 

 processes have been described, and the conclusion 

 arrived at is that, although success does not appear to 

 have been attained, the conversion shows promise. 

 Two main groups of methods have been used : (i) The 

 synthesis of fatty acids from hydrocarbons of low 

 molecular weight, such as ethylene and acetylene, by 

 polymerisation and oxidation, and (2) the partial de- 

 gradation and oxidation of hydrocarbons of high mole- 

 cular weight. In the Zelinsky process a chlorinated 

 hydrocarbon was treated by the Grignard reaction for 

 the production of fatty acid. This process is said to 

 have been in use in Germany in the later years of 

 the war. Harries treated unsaturated hydrocarbons 

 of high molecular weight with ozone, decomposed 

 the ozonides with steam, and transformed the result- 

 ing peroxides into fatty acids by treatment with 



