226 Scientific Proceedings, Royal Dublin Society. 



with holes, and let into the wall close to the floor under the head 

 of the bed. The conjoint area of the holes might have been about 

 20 square inches on a liberal estimate. Their ventilating value 

 must have been seriously diminished by their position close to the 

 floor ; they opened into the corridor. Assuming the admitted air 

 to be cooler than that already in the room, the effect would 

 be to form on the floor a stratum of purer air, which could 

 only slowly affect the composition of the general atmosphere 

 of the room. The wall-bracket was furnished with a No. 5 

 brased fish-tail burner, consuming about 5 feet of gas per 

 hour. 



The fatal result was in this case due to several circumstances, 

 of which the leading one was undoubtedly the escape of gas ; 

 whilst the defective ventilation of the apartment, in which the 

 unfortunate couple were allowed to remain shut up without food 

 or attendance throughout the entire day, was a contributory factor. 

 On comparing the ventilation with the recognised standards, we 

 find that the cubic space was 517 feet per head (instead of 1,000). 

 The functional " fresh " air inlet was only 8 square inches ; but 

 allowing the same value for any advantage that might have 

 accrued from the perforated zinc plate beneath the bed, let us say 

 16 square inches (instead of 48). Of course, air can enter through 

 any crevice. Dr. Haldane has shown that the air of such a 

 room is changed, even in the absence of a fire-place, about once 

 every 2£ hours. It would, therefore, be quite a mistake to 

 suppose that the ventilation of a room, with, at any rate, one of its 

 walls an outer one (that is, forming part of the outside of the 

 house), is solely dependent on the ventilation apertures made 

 ad hoc. Pettenkofer experimented many years ago with a room of 

 about 3,000 cubic feet capacity, and found that without definite 

 ventilation, the air was changed once every 3 or 4 hours. Dr. 

 Haldane, in his Appendix to the Gas Commission Report, concludes 

 that the air of a closed room of 1,000 cubic feet capacity is changed 

 once in from 2 to 3 hours. It may be interesting to inquire what 

 was the condition of the air of this particular bedroom, assuming 

 that the air was completely changed once every 2| hours by 

 diffusion through the walls, and, for the sake of ease in calcula- 

 tion, that its cubic content was 1,000 (instead of 1,034) cubic feet. 

 We shall also assume that the gas continued burning for 2 hours 



