322 Ozonei 



we are treading the same peaceful path of knowledge, we are 

 assembled under the broad, the vast canopy of the American fir- 

 mament, the gentle breeze that wafts the red cross banner of St. 

 George and Merry England, alike unfurls, the stars and stripes, 

 the emblem of your land of freedorn. Long may these two flags 

 entwine in peace, in kindred folds, and may that master-piece of 

 scientific genius, the electric cable, which is at this moment being 

 laid beneath the Atlantic sea, whose waves science has measured 

 with a mighty span, be the peaceful band, that will cement more 

 firmly the destinies of the two great nations of the earth, under 

 the benign and able guidance of your worthy President, and our 

 beloved Queen, and may science, which knows no country, no 

 nation, no' language, be rendered more subservient to the happi- 

 ness and welfare of the whole human family. 



A year has now passed since the deputation from this place en- 

 joyed the hospitalities of one of your large cities, the familiar and 

 friendly faces of many we met there, and now present, calls to 

 mind many pleasant recollections, but like all things mundane, we 

 have some cause for sadness, for in the few fleeting moons that 

 have waned since last we met, death has taken from our midst a 

 Redfield, a Bailey, and a Mitch el, each pre-eminent in his department 

 of scientific research, and to science" and us, an irreparable loss, 

 and the Association has done itself honor in paying a tribute to 

 their memories ; but the midnight lamp of the man of science 

 must grow dim, the, experimentalist must for ever quit the busy 

 scenes of his laboratory, the eye of the astronomer must be closed, 

 for the life of the philosopher is but mortal. 



It is my intention to lay before the section the results of obser- 

 vations made on the amount of ozone present in the atmosphere. 

 The place of observation is at St. Martin's, about 9 miles due west 

 of Montreal, and is 118 feet above' the mean level of the sea ; it 

 is situated in the centre nearly of the Isle Jesus, an island sur- 

 rounded by the branches of the Ottawa, the place of observation 

 is a little more than 3 miles from the river, thus being sufficiently 

 inland, to be removed from any transient vapour or fog, which is 

 often present in the proximity of rivers ; it is a fiat island, and the 

 whole of the neighborhood is under cultivation. 



It is not my purpose to enter into a lengthy detail of the che- 

 mical composition of ozone, enough for our present purpose to 

 define it to be, a compound of oxygen, analogous to the per-oxide 

 ' 1 hydrogen, or that it is oxygen in ap allotropic state, that is 



