An Automatic Recorder of Smoke Pollution

Abstract

IN an article on “London Air” in the Times of August 23 Sir Napier Shaw directed attention to the clear atmosphere which was such a noticeable feature in all industrial centres during the recent coal strike. The article in question is, however, chiefly interesting for its description of an ingenious self-recording contrivance invented by Dr. J. S. Owens for the Atmospheric Pollution Committee of.the Meteorological Office, which registers hourly the amount of solid atmospheric impurities. A fixed volume of air is aspirated through a small disc of filter-paper, and from the depth of shade the amount of deposit is estimated by comparison with discs of standard shades. In London the notably dirty period is, from 9 a.m. to 5 p.m., i.e. the business hours of the day. The greatest impurity, is, of course, in winter, that of a May day being about one-quarter that of a November day. The day impurity in May is of the same order as the night impurity in November. The instrument should prove useful in detecting any noticeable improvement or otherwise in the amount of solid impurities in different towns. Although Sir Napier Shaw states that these measurements of the Committee “are noteworthy as the first series of systematic observations of the pollution of the air of London and other centres of population,” he has apparently overlooked the fact that a complete series of records was made in Leeds some years previously, in the course of which it was clearly established not only that the domestic fireplace is responsible for much the larger, proportion of the soot emitted from burning coal, but also, more important still, that this domestic soot is much more highly contaminated with tar than that from factory chimneys. In his reference to possible means of smoke prevention from domestic fireplaces, Sir Napier Shaw makes no reference to the carefully considered report which was published in the autumn of last year by the Committee on Smoke Abatement appointed by the Ministry of Health. It was there pointed out that the ordinary open kitchen range was wasteful and inefficient, and the Committee strongly insisted on the advantage of gas-cookers where gas was available. Low-temperature coke was also advocated whenever the right sort of material could be placed upon the market—a desideratum not yet attained. But there are numerous forms of improved ranges in which coke and anthracite can be burned much more economically than in the old open range, and, of course, without the emission of smoke. It now remains for the Ministry of Health to bring pressure to bear on those engaged upon Government building schemes to adopt these recommendations. It has a unique opportunity for setting an example in atmospheric purification.