244 



NATURE 



{Jan. 27, 1876 



a room in which three, four, or five gas flames have been 

 burning for hours without either door or window having 

 been open ; that the people who live in these rooms escape 

 the evil effects is not to be supposed. The only thing is 

 that they have not sense or courage enough to trace the 

 effects to their cause. Rather than give up their warmth 

 and light they wilfully close their eyes to what follows. 

 When people inflict these miseries on their friends, 

 whether consciously or not, they become a positive 

 nuisance, and are fit subjects to be dealt with by the 

 sanitary inspector. To have to dine with them is a 

 punishment : a headache is sure to follow, however ab- 

 stemious one may be. 



Many of these people are doubtless innocent, but 

 there are those who know the evil, yet who do not make 

 any attempt to remove the cause. They have only to 

 turn down the gas. But no ; they clamour for what they 

 cannot get — good ventilation with the gas — and number- 

 less are the quack remedies which one sees applied. But 

 whether impossible or not, it is certain that at present 

 there is no proved means which will supply sufficient air, 

 free from draughts, to keep a room blazing with gas 

 decently fresh. It may be that in time, when the clamour 

 of quacks has sufficiently subsided to allow the voice of 

 reason to be heard, some method of constructing houses 

 •with chimneys for gas may be introduced which will 

 allow of all the desired warmth and light, and at the same 

 time ensure a sufficient supply of fresh air. But in the 

 meantime, the obvious remedy is to forego some of the 

 luxuries, to be content with moderate light and warmth, 

 and to set off against the evils (mostly fancy), which arise 

 from occasionally opening a window, the certain and dis- 

 gusting eff"ects of sitting in a closed room. 



The effect of gas is not the only evil to be remedied by 

 improved ventilation. Modern science has brought to 

 light things concerning the origin of disease of which our 

 fathers never dreamed, and which must render people 

 dissatisfied with the state in which they live. But to do 

 this they must be known. Ignorance, if it is not the sole 

 cause of the evils which people inflict on themselves, is 

 at least their excuse. As a rule people have much more 

 faith in what is told them with authority than in that 

 which they themselves dimly perceive, and hence it does 

 not follow that because the evidence of their noses has 

 been disregarded that the voice of a prophet will not be 

 listened to. Unfortunately, the subject of practical ven- 

 tilation is one which by reason of its complexity has 

 offered little attraction to scientific men, and conse- 

 quently has been much neglected. It was therefore with 

 great pleasure that we received the work before us. 

 Written in ordinary language, and in a very clear style, 

 this little book contains an account of all that has been 

 done in the way of scientific research on the relation of 

 air to life. It is written from a scientific point of view, 

 but no pains have been spared to trace the possible appli- 

 cations of the science and the practical lessons which 

 may be learnt from it. It is just the book for those who, 

 without any particular chemical or physical training, have 

 undertaken the control of sanitary matters. 



In the first two chapters the author gives a very in- 

 teresting historical sketch of the discovery of the con- 

 stituents of the atmosphere, in which the experiments 

 which have led to the various discoveries are not only 



described, but illustrated by very perfect drawings, and 

 thus the reader is conducted by easy steps to a very 

 complete view of the subject, including the most recent 

 discoveries. A very full account is given of the amounts 

 (and the means of determining them) of ozone, carbonic 

 acid, and the organic impurities in the air at different 

 times and in different places. The degree of accuracy to 

 which this class of research has been carried is very 

 striking. Dr. Angus Smith has examined the air under 

 almost all conceivable circumstan^s, and his methods 

 will compare in delicacy with the sense of smell. Thus 

 in place of our impressions, we have now definite chemical 

 proof as to the degree of impurity in the air which pro- 

 duces evil effects. 



Having given tables of the amounts of carbonic acid to 

 be met with in closed places, the author proceeds :— 



" Here it is easily seen that the air in the theatres is 

 very bad ; but after the doors had been open for a short 

 time between the acts it rapidly improved j indeed, in 

 Covent Garden, in the second case, near an open door, 

 the people exclaimed, by force of contrast, how delightful 

 the fresh air was ; nevertheless, this fresh air contained 

 I4*8 parts of carbonic acid in 10,000, or from 2^ to three 

 times as much as it should have had. Drury Lane was 

 the first place experimented on ; and having entered at 

 the commencement of the performance, the bad effect of 

 the air as it became vitiated wasonly gradually expe- 

 rienced, but it produced a listles'sness and headache. 

 All the audience around were evidently affected in the 

 same manner, and appeared to be constantly sighing and 

 gaping, or, in other words, gasping for breath." 



" The bad effect of carbonic acid in the air alone, with- 

 out taking into account organic matter, has been shown 

 by Dr. Angus Smith, who ascertained that one part of 

 the gas in 1,000 of air produced in fi teen minutes an \\\- 

 crease in the number of respirations from eighteen to 

 nineteen per minute, which increase remained the same 

 up to forty-five minutes ; the pulse was lowered in twenty- 

 five minutes from seventy-three to seventy-one beats ; 

 while at forty-five minutes it was seventy-two per minute. 

 With 2^ volumes of carbonic acid in 1,000 of air the pulse 

 at first seventy, increased to seventy -three at the end of 

 ten minutes, and at the end of half-an-hour was lowered 

 to sixty-nine, while the respirations increased from seven- 

 teen to twenty-one per minute. With five volumes of 

 carbonic acid the pulse at first seventy-six and the inspi- 

 rations seventeen, at the end of forty minutes were repre- 

 sented by the numbers seventy-one and twenty- four," 



The results of this research, therefore, fully bear out 

 the conclusions of experience as to the evils of our pre- 

 sent system of lighting our dwellings, and it is to be 

 hoped that, supported by this authority, people will no 

 longer snub their noses and disregard their evidence. 



The author then goes on to discuss the laws relating to 

 the motion of gases, and to detail what little is known as 

 to the best means of getting the air into and out of our 

 rooms. He calls attention to the very striking result of 

 some experiments (Pettenkofer's) as regards the quantity 

 of air which passes through the solid walls of a room ; 

 and he finishes the chapter by pointing out how in our 

 badly-constructed houses we are drawing poisonous air 

 into them from the ground on which they are built, and 

 the drains beneath them. 



The latter part of the book is devoted to setting forth 

 the results of the researches of Dr. Angus Smith, Pas- 

 teur, and others, on the power of tne air to suspend and 



