330 



NATURE 



[June 26, 19 19 



labour and output, a reduction of 8^ hours per week 

 (from 68-2 hours to 597 hours) increased the gross 

 output by 8 pef cent. 



From an analysis of more than half a million ad- 

 missions to sick report of troops in camps in the 

 United States, of whom 531,445 were white and 

 15,186 coloured, Lt.-Col. A. G. Love and Major 

 C. B. Davenport form a comparison of white and 

 coloured troops in respect to incidence of disease. 

 As regards total relative frequency of disease in the 

 two races, the coloured troops were about ig per 

 cent, more liable to go on sick report than the white 

 troops. The coloured troops were relatively less 

 resistant to diseases of the lungs and pleura as well 

 as to certain general diseases, like tuberculosis and 

 smallpox ; they are also much more frequently in- 

 fected with venereal diseases. But the uninfected 

 negro is highly resistant to diseases of the skin, 

 mouth, and throat; he seems to have more stable 

 nerves, has better eyes, and metabolises better (Proc. 

 National Acad. Sciences, vol. v., p. 58, 1919). 



Dr. H. H. Laughlin has made a cytological and 

 statistical study (Carnegie Inst. Washington, Publica- 

 tion No 265, pp. 48+18 tables) of the relative and 

 absolute durations of the several arbitrarily delimited 

 progress-stages in cell-division. His material was 

 found in the root-tip cells of the common onion. 

 With great carefulness Dr. Laughlin has determined 

 the duration of ten successive stages at temperatures 

 of 10° C, 20° C, and 30° C. The total period at these 

 three temperatures was 292-52, 24097, and 9156 

 minutes respectively. The resting stage counts for 

 194-92, 159-57, and 33-26 minutes ; the early prophase 

 for 52-2550, 592592, and 51-4147. Thereafter the 

 changes take place very rapidly. The velocity increase 

 at a given temperature' compared with the velocity of ' 

 the same stage at 10° C. lower (what is known as 

 the Q,„ value) approximates to the expectations 

 deducible from van't Hoff's law. That is to say, 

 the mitosis behaves in its velocity increments to 

 temperature-increments like the simpler chemical re- 

 actions. But this does not mean that mitosis is " a 

 simple chemical reaction." Far from it; we have to 

 deal with a rdpertoire of activities, a vast complex 

 of physical and chemical activities, in which the 

 many aberrations from the velocity-gradient of a 

 simple chemical process are mutually cancelled. The 

 author's study marks a distinct step of advance in 

 the analysis of mitosis. 



The "tillite" with scratched boulders in the 

 Varanger district of Finmarken is referred by Olaf 

 Holtedahl, of Kristiania (Amer. Journ. Sci., vol. xlvii., 

 p. 85, 1919) to a pre-Caledonian epoch, probably 

 Ordovician. A comparison is made with the coarse 

 conglomerates of Girvan in Ayrshire. The paper 

 reviews the Palasozoic rocks of Finmarken, and 

 assigns an inorganic and concretionary origin to the 

 structures known as stromatolites, including Crypto- 

 zoon and Gymnosolen. The author cannot agree with 

 Walcott that the limestones containing these objects 

 were accumulated in fresh water, but he thinks that 

 algal activities may have aided in the deposition of the 

 calcium carbonate. 



'The zoning of the "Karroo System" of South 

 Africa, which is in reality the representative of more 

 than one system, receives a new investigation from 

 Mr. A. L. du Toit in the Proceedings of the Geo- 

 logical Society of South Africa for 1918 (p. xvii). 

 The author carries the glacial Dvvyka series down into 

 the Upper Carboniferous, and the Ecca beds thus 

 become Lower Permian. The Cave Sandstone at the 

 top of the Karroo formation is regarded as an aeolian 

 deposit of probablv Rhaetic age, comparable with the 



NO. 2591, VOL. 103] 



Pleistocene loss of the northern hemisphere. The 

 former wide extension of the overlying Drakensberg 

 lavas, including the basalts along the Zambesi, is 

 indicated, and these are also brought, so far as present 

 evidence goes, within the Rhaetic series. 



The Press of Aragon (Spain) has recently published 

 a description of trials made by a Spanish engineer 

 of straw-compound as a substitute for coal. This 

 fuel is said to have great advantages over coal for 

 locomotives and agricultural tractors, as it develops 

 suflficient heat in thirty minutes to give the necessary 

 head of steam. The U.S. Commerce Report No. 86 

 (1919), reporting this discover}', states that the ashes 

 left by the fuel in question make an excellent fertiliser. 

 Another Spaniard has patented a process for the use 

 of banana fibre for textiles, yarns, cords, and alpar- 

 gata soles as a substitute for hemp and jute. Trials 

 have proved satisfactory, and plant is to be laid down 

 to work the process. 



The recently issued annual report of the Decimal 

 Association shows that the efforts of the association 

 in favour of the compulsory introduction of decimal 

 coinage and the metric system of weights and 

 measures continue to make satisfactory progress. The 

 Bill brought forward by Lord Southwark last year 

 has aroused the interest of many public bodies, and 

 numerous resolutions have been passed in favour of 

 decimal coinage. The measure will remain in abey- 

 ance until the Royal Commission appointed to deal 

 with the subject issues its report, which is expected 

 in the early autumn. A number of local educational 

 bodies have signified their approval of the proposal 

 to introduce the metric system of weights and 

 measures. British Chambers of Commerce abroad 

 are actively supporting the proposed reform, as they 

 regard the adoption of the metric system by this 

 country as an essential preliminary to success in 

 supplanting German ascendency in foreign markets. 

 Although the use of the system has been for many 

 vears permissive in the United Kingdom, business 

 firms adopting it suffer much inconvenience owing to 

 the railway companies refusing to accept consignment 

 notes made out in terms of metric weights ; this diffi- 

 cultv will continue to hamper progress until the system 

 is made obligatory. The Decimal Educator, a 

 quarterly journal started by the association during the 

 vear, has met with a marked measure of success. 



With reference to Irish reconstruction problems, 

 the question of producing industrial alcohol was dis- 

 cussed by Dr. J. Reilly, of the Royal Naval Cordite 

 Factory, in a lecture delivered before the Royal 

 Dublin Society a short time ago. One of the chief 

 points suggested for consideration was whether, by 

 the use of alcohol as a motor-fuel, the dependence of 

 this country upon foreign supplies of petrol could 

 not be obviated or lessened. We import about 

 150,000,000 gallons of petrol yearly. To replace this 

 by alcohol obtained from potatoes about 7,000,000 tons 

 of the latter would be required. Allowing for rota- 

 tion crops, this quantity of potatoes would_ require 

 some 6,000,000 acres of land for its production. At 

 present Ireland grows about 4,000,000 tons of pota- 

 toes per annum. She could grow more, no doubt, 

 though how much more is not at present very clear. 

 Assuming that the requisite amount of land could 

 be spared after food needs were supplied, the prac- 

 tical tesit of the matter would be the price of the 

 alcohol produced in relation to that of petrol. As to 

 this the lecturer gives no dogmatic pronouncement; 

 he only suggests that there is a case for considera- 

 tion. In a countrv such as Ireland, with a large 

 agricultural population, it is essential for prosperity 

 that the land should be made to orovide more wealth, 



