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extremely sensitive appliances used in demonstrating this special 
class of meteorological inquiry. In the chamber, which is 
situated several feet below ground, are three powerful magnets— 
one pointing east and west, another north and south, while the 
third regulates the ‘“‘dip.”” Connected with these are photo- 
graphic magnetographs, which tell the story of the earth’s electric 
current. It was noted that this subterranean chamber was at 
some distance trom the observatory in which the large equatorial] 
telescope is found; the explanation for which can be traced in 
the fact that the magnets would have exercised an adverse 
influence upon the astronomical machinery had they been placed 
in itsimmediate neighbourhood. Mr. Cortie explained the power 
and influence of these magnets, and the peculiar way in which 
they were acted upon by the earth’s currents. Two visits were 
paid to the Observatory, where, through the large telescope, the 
image of the sun was thrown upon drawing paper. Here every 
day the sun is sketched, and the number of spots, their position 
and shape, and facule, are clearly delineated by the astronomical 
draughtsman. At eleven o'clock on the morning of the visit of 
the club these observations had been taken, and the sketches 
remained upon the paper. ‘lhe members had, therefore, the 
opportunity of seeing the difference in the shape of the spots on 
the sun as they appeared six hours after delineation. Some 
interesting information was imparted relating to sun-spots. That 
month (June) was about the season of their minimum appearance, 
and it took from 18 to 14 days (according to the latitude on the 
sun when they appeared) for them to cross the disc from side to 
side. An interesting feature in connection with the drawings 
was their comparison with those made of the same spot, at the 
same hour, at other and distant observatories. The observations 
are thus put to a crucial test, and the results are indicative of 
the highly skilled care and minuteness which the patient investi- 
gation of this class of solar phenomena is receiving at the hands 
of astronomers at the present day. It was intended on the second 
visit to the Observatory that the visitors should have been shown 
the spectrum analysis ; but there had not been time to fix the 
necessary instruments in order to secure this pleasure. Mr. 
Cortie, however, explained the instrument which was used in 
connection with the telescope to obtain this wonderful effect, 
which has contributed so largely to our information in determin. 
ing the character of the sun’s photosphere. The method of 
working the magnificent equatorial telescope itself was shown 
and a description given of the clockwork arrangement attached, 
which, by keeping time with the axis of the earth, ingeniously 
retained the celestial body under observation within the field of 
the telescope and before the eye of the explorer, though the 
rotation of the earth goes on. Space at disposal will not. permit 
