SFFECTS OF DEFICIENT VENTILATION. 181 



I do not mean to say, that in these cases the fatal 

 results were attributable exclusively to vitiation of 

 the air by breathing. Fixed air may have been dis- 

 engaged also from some other source ; but the de- 

 teriorating influence of respiration, where no venti- 

 lation is perceptible, cannot be doubted. According 

 to Dr. Bostock's estimate, for example, an average 

 sized man consumes about 45,000 cubic inches of 

 oxygen, and gives out about 40,000 of carbonic acid 

 in 24 hours, or 18,750 of oxygen and 16,666 of car- 

 bonic acid in ten hours, which was nearly the time 

 which the sufferers had remained in the cabin before 

 they were found. As they were two in number, the 

 quantity of oxygen which would have been required 

 for their consumption was of course equal to 37,500 

 cubic inches, while the carbonic acid given out 

 would amount to upwards of 32,000 inches a source 

 of impurity manifestly quite equal to the production 

 of serious consequences to those exposed to it ; and 

 which no one, properly acquainted with the consti- 

 tution of his own body and with the conditions 

 essential to healthy respiration, would ever have 

 willingly encountered. It is no argument to say 

 that the cause of death must have been some dis- 

 engagement of gas within the vessel: for, even 

 granting this to have been the case, it is still certain 

 that, had the means of ventilation been adequately 

 provided, this gas would have been so much diluted, 

 and so quickly dispersed, that it would have been 

 comparatively innoxious. 



In the construction of our houses, the laws of 

 respiration are often glaringly infringed, especially 

 in towns. The public rooms, which can be easily 

 ventilated at any time, which are in fact ventilated 

 by the constant opening and shutting of the door, 

 and by the draught of the chimney, and in which, 

 therefore, large dimensions are less necessary for 

 salubrity, are always the most spacious and airy. 

 The bed-rooms, on the other hand, in which, from 

 Q 



