524 



NATURE 



[December 22, 1921 



the necessity of allowing- the development of the 

 gas industry to proceed, without any check on its 

 natural progress." 



Such was the Committee's conclusion on the 

 matter, but it was qualified by the suggestion 

 "that the Departments concerned should carefully 

 watch the situation so that, if the freedom from 

 limitation which we recommend is accompanied by 

 unexpectedly unfavourable results, the attention 

 of Parliament may, if necessary, be again directed 

 to the matter," as though the Committee had still 

 some misgivings about its verdict and did not 

 consider it as final. Certainly, in the light of 

 statistics relating to accidental gas poisoning 

 placed before the Committee by the Registrar- 

 General's Department, and ^those published for 

 the years 1914-19 by the Gas and Electric Light 

 Commissioner of Massachusetts, which are 

 referred to in the Report, there would appear to 

 be a much greater risk of accidental death from 

 carbon monoxide poisoning in localities where 

 coal-gas largely diluted with water-gas is supplied 

 than in those in which no water-gas is added. 

 Indeed, it seems arguable that, had the matter 

 been decided mainly by such statistics, and on the 

 physiological evidence, rather than on those of the 

 cheaper production of gas, a verdict in favour of 

 limitation would have been the more natural and 

 appropriate one. 



There is admittedly much to be said on hygienic 

 grounds in support of the argument for cheaper 

 gas, especially in view of the great improvements 

 made during recent years in gas fires, and their 

 consequent wider adoption for the heating of 

 living rooms which are in use for part of the day 

 only. For such purposes, as well as for cooking, 

 gas is still an economical fuel, not so much on 

 grounds of its initial cheapness (for it is a rela- 

 tively dear fuel as compared with coal), as on 

 those of convenience and cleanliness. It may, 

 however, be argued perhaps with even greater 

 force that, for the ordinary living rooms of a 

 house, which require to be heated all day long, 

 there is probably nothing more healthy and eco- 

 nomical than radiation from red hot semi-carbon- 

 ised coke burning in an open fireplace, and that it 

 is in such direction, rather than that of gas heat- 

 ing, that the ultimate solution of the domestic 

 smoke nuisance mainly lies, although undoubtedly 

 each method will contribute to the desired end. 



The Committee does not appear to have con- 

 sidered at all the question of the greater risks of 

 back-firing and explosions arising out of the much 

 wider range of explosibihty of coal-gas when 

 NO. 2721, VOL. 108] 



largely diluted with water-gas for a domestic 

 supply, although this is a matter of some import- 

 ance. Moreover, it seems to have been overlooked 

 that whereas the gas supply of many American 

 cities may contain as much as 25 to 30 per cent, 

 of carbon monoxide, yet it would be of a much 

 higher calorific standard {vide that of New York) 

 than any gas supplied, or likely to be supplied, 

 under the new regulation by British undertakings. 

 Indeed, it is a matter of mere arithmetic that an 

 American burner supplied with gas of 675 B.Th.U. 

 per cb. ft., and containing 27 per cent, of 

 carbon monoxide, would, for a given heat develop- 

 ment in the flame, actually pass somewhat less 

 carbon monoxide in a given time than a British 

 burner supplied with a 475 B.Th.U. gas con- 

 taining only 20 per cent, of carbon monoxide. 

 It may, however, be hoped that British gas under- 

 takings will, in their own interests, voluntarily 

 work within such a 20 per cent, limit, and that 

 gas consumers generally will fully realise the im- 

 portance of keeping a sharp look-out for gas leak- 

 ages and of using only the best-made taps and 

 fittings. W. A. B. 



Diseases of the Rubber Tree (Hevea 

 braziliensis). 



The Diseases and Pests of the Rubber Tree. By 

 T. Fetch. Pp. x + 278 + 6 plates. (London: 

 Macmillan and Co., Ltd., 192 1.) 205. net. 



THE growth of the rubber plantation busi- 

 ness, in which many millions sterling of 

 British capital are invested, provides a striking 

 example of the advantages that accrue from the 

 combination of science and industry. It is, in- 

 deed, not too much to say that but for this com- 

 bination the rubber planting industry, as it has 

 flourished during the last ten years or more, could 

 scarcely have maintained its existence. 



It is not necessary to direct attention to the 

 essential aid which science has given in enabling 

 the raw rubber to be fitted for its various com^ 

 mercial applications. On the other hand, thi 

 present extensive development of rubber i 

 industry would not have been possible had not' 

 scientific help been at hand to enable the planta-, 

 tions themselves to be maintained. In the earlier] 

 days, as in many another tropical agricultural in 

 dustry, all went very well with the planter — and| 

 then came the inevitable onset of disease, which 

 under tropical conditions of growth may, and if 

 unchecked will, easily assume serious propor- 

 tions. The first serious check in the history of the 

 plantation enterprise came in the form of a root 



