408 



Messrs. L. Hill and M. Flack. 



[July 6, 



our experimental chamber with the smoke of shag tobacco, ammonium 

 sulphide, or carbon bisulphide vapour. At other times we placed in the 

 chamber stinking meat, or human faeces. After putting in action the two 

 small ozonisers, placed in the roof of the chamber, for two minutes, we were 

 not able to detect the odours of these substances. The smell of the ozone 

 masked all other smells. The masking of these smells gives no proof of 

 the destruction of the evil-smelling emanations, for Zwaardemaker has 

 shown that two smells can neutralise each other, e.g., ammonia introduced 

 up one nostril, and acetic acid up the other. 



Erlandsen and L. Schwarz* concluded, from a series of careful obser- 

 vations on the effect of ozone on ammonia and hydrogen sulphide, 

 trimethylamine, butyric and valerianic acids, indol and skatol, that the 

 smells are only masked and not destroyed by the presence of ozone. The 

 odoriferous substance and ozone were introduced into the chamber together. 

 After a period the ozone disappeared from the chamber, and the smell 

 was found to have returned. The smell of tobacco, in particular, was masked 

 and not destroyed. 



From a hygienic standpoint the ozone may be useful as a deodoriser, 

 since, from the point of view of its effect on the nervous system, it does 

 not matter whether the evil smell is masked or destroyed. The question is 

 which is preferable, the evil smell or the smell of ozone. Certain smells are 

 objectionable, and become more so if persistent and uniform. In cold meat 

 or dry goods stores, tube railways, etc., ozone may have its use as a 

 deodoriser and freshener of the atmosphere, relieving the stale and tedious 

 quality of the air. 



In a room fitted with a gas radiator (without flue) we have found, by 

 a series of daily observations, that ozone relieves the disagreeable quality 

 of the air. It seems to give a certain tang to the air, and, by stimulating 

 nerve-endings in the respiratory tract, relieves the monotony of over-warm 

 and close air. We were informed by an engineer employed in a large 

 public office that he added " Sanitas " to the water used for spraying and 

 cooling the air which was pumped into the building on a Plenum system. 

 In the late afternoon the clerks often telephoned down to him and asked 

 for " more Sanitas " — anything to change the monotony of air always 

 warmed to 65° F. 



Under the conditions of natural life we are " blown upon by every wind, 

 and wet with every shower." The cutaneous sense organs are submitted to 

 ceaseless flux of physical and chemical conditions, more or less blood and 

 tissue lymph, higher or lower temperature, etc. The heating and ventilating 

 * 'Zeit. f. Hygiene u. Infections-Krankheiten,' 1910, vol. 67, p. 391. 



