PHYSIOLOGICAL INFLUENCE OF OZONE—HILL AND FLACK. 621 
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 neutralize 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 
observations on the effect of ozone on ammonia and hydrogen sul- 
phide, 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 deodorizer, 
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 deodorizer and freshener of the atmos- 
phere, 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 monot- 
ony of overwarm 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 engineer has aimed at giving us in our build- 
ings a uniform summer temperature, unchanged by wind or calm, 
warm sunshine, or cold shadow of the clouds. In the House of Com- 
mons the air is drawn in from over the Thames, cooled and wetted by 
a water spray, and carried in at the rate of 40,000 to 50,000 feet a 
minute—a fine bracing current. Before it reaches the House it is 
warmed by passing over steam radiators, mixed, and passed in a 
uniform draftless stream at 63° F., through the gauze-covered floor 
1 Zeit. f. Hygiene u. Infections-Krankheiten, 1910, vol. 67, p. 391. 
