380 THE CANADIAN NATURALIST. [June 



Winds influence the amount of Ozone, the amount depending upon 

 the quarter from which they come, and in some cases on their velo- 

 city : easterly and southerly winds may be called ozonic winds, while 

 westerly and northerly winds barely ever indicate a trace. Rain 

 and snow generally give indications of a large amount. A N.E. 

 land wind does not generally indicate Ozone ; whenever there 

 is Ozone in a N. E. wind it may be attributed to the sea-breeze 

 passing over the land, for we have very often, in this vicinity, a 

 dry N. E. wind with a very high barometer for some days, 

 with no indications of Ozone. Atmospheric temperature does 

 not seem to influence the amount ; I have observed its presence 

 at some 30° to 40° below zero, and at 98° above zero, Fahren- 

 heit. 



The variation in its daily amount, has been the source of some 

 discussion. Observations were carried on for some years at the Isle 

 Jesus observatory, by means of a movable ozonometer, time 

 being taken as an element ; the strips of calico were by a simple 

 contrivance passed over an opening exposed to light and air at 

 the rate one inch per hour. From upwards of 3000 observations, 

 tending to confirm this important point, it was found that the 

 increase and decrease of the daily ozonic periods corresponded in 

 a striking manner to the bi-daily variations of the atmospheric 

 humidity. There were also some slight fluctuations corresponding 

 in a marked degree to the bi-daily variations of the barometer. 

 Upwards of 20,000 observations on Ozone have been taken and 

 recorded, and I am ashamed to say, unaided, thus depriving 

 us of any means of comparison, or confirmation ; but I can but 

 express a wish that brighter and better days will come in the 

 future, and that observers will not be found wanting to set at rest 

 the important problem of the effects of the absence or presence of 

 Ozone on the health of animals and vegetables. Assuredly, a 

 substance which has been found to exert an important bearing on 

 the health of individuals, and upon the agricultural and commer- 

 cial wealth of nations, demands from men of science a calm and 

 patient investigation. It requiries, for its due prosecution, a 

 systematic method of recording its amount ; it is for common 

 purposes observed twice in twenty-four hours, and a mean of the 

 two observations is recorded, and also a register of rates of disease 

 and mortality, and a correct register of the nature of these diseases ; 

 these of course must be simultaneous with the usual meteorological 

 observations, of atmospheric pressure, temperature and humidity, 



