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112 THE PRESIDENTS ADDRESS. 
this Province has hitherto chiefly concentrated its intellectual energies : 
the Geological Survey and the Magnetic Observatory, Montreal and 
Toronto are named with pride wherever science is cultivated and know- 
ledge revered. There is something grand and ennobling in reflecting 
on the patient labors of the Magnetic, as of the Astronomical observer. 
Tn that little building which rears its modest tower in the University 
Park, apart from all our busy thoroughfares, on a spot so recently 
hewn out of the forest wilderness, observers are patiently noting, 
day by day, the minutest phenomena connected with the elements of 
terrestrial magnetic force, the laws of periodicity, the number, diversi- 
ty of forms, and intensity of auroral manifestations, and the indications 
of a solar magnetic influence on the earth, dependent, as it seems, on 
the changes which the luminous envelope of the sun undergoes. A 
larger series of magnetic phenomena completes its cycle of variations 
from the ordinary mean within a decennial period, which coincides 
with a similar one observed in the solar spots ; and a variation of the 
magnetic declination has also been traced, chiefly by means of our own 
Toronto observations, to lunar influence ; while it has been conclusive- 
ly established that the elements of the earth’s magnetic force are 
subject to regular diurnal, annual, and decennial ranges of variation 
from maximum, through minimum, to maximum again. By such 
observed data glimpses of novel truths of the most remarkable and 
unexpected kind are being obtained. Through a source so unlikely 
as our observation of the phenomena of terrestrial magnetism, we 
are learning somewhat of the constitution of the central luminary 
of our system. ‘Towards the close of last century, amidst an abso- 
lute ignorance of any known data to reason upon, much ingenious 
speculation was indulged in relative to the nature and constitution 
of the sun. In seeking to interpret observed solar phenomena, Sir 
William Herschell was led to the conclusion that the central body 
of our system is probably an opaque globe, surrounded by a luminous 
atmosphere, the disturbance of which he accounted for by the emission 
of an elastic fluid, ascending from the solid body, and producing by 
its currents those solar spots, to which our attention has been recent- 
ly drawn by a series of interesting communications from one of our 
own number. 
The recent ingenious application of photography by Sir John 
Herschell, for following up the speculations of his father, and making 
the sun record for us the daily changes wrought on its own luminous 
surface, is another means whereby materials for further philosophical 
