LXXIV ROYAL SOCIETY OF CANADA 
The grating at first used in connection with the coelostat gave very 
imperfect definition unless a considerable part of it was covered. This 
has been replaced by a new grating which gives much better results. 
The lens of the stellar camera has been refigured to get rid of 
spherical aberration which produced halos about the star images. Its 
performance is now very good. For photographing comets, a special 
camera with a wide angle lens has been procured. In use this is 
attached to the upper end of the telescope of the equatorial. 
The stellar camera and the spectrograph are both attached to the 
large equatorial, and can seldom be used at the same time. Thus the 
full use of either instrument is hindered. To obviate this, it is proposed 
to procure a separate equatorial mounting for the camera. A small 
building to accommodate it is in course of erection on the Observatory 
grounds. 
Two outside azimuth marks for the meridian circle are also in 
course of construction. The reference marks will be underground. 
Continuous records of earth movements have been kept with the 
seismograph. This instrument is a highly sensitive one, and its records, 
being made photographically, indicate many minute movements which 
are lost through friction in instruments having mechanical registration. 
Moreover the time scale of the records is accurate, being operated in 
connection with the time distribution system, whereby no correction for 
clock error is needed. It is believed that in these respects the instal- 
lation cannot be equalled on this continent. 
Continuous records also have been kept, with the self registering 
instruments, of the small changes of air temperature and pressure. It 
is proposed to add to the equipment an electric self-registering anemo- 
graph, to record direction, velocity, and pressure of the wind. A struc- 
ture to carry it is being erected on the Observatory roof. 
The operations of the magnetic survey of Canada during 1909 com- 
prised observations at 33 stations along the north shore of the River and 
Gulf of St. Lawrence, extending as far as Blane Sablon. At each station 
the declination, inclination and horizontal force were observed, as well 
as the diurnal variation in declination. The results of this expedition 
will be the more valuable, in that hitherto few magnetic observations 
have been taken in that region. 
During the present season magnetic observations are being made at 
frequent intervals along the main line of the Canadian Pacific Railway 
from Lake Superior to Regina, also at many points in the Province of 
Ontario. 
Astronomical latitudes and longitudes were determined for geo- 
graphical purposes at fifteen stations, including seven in the Maritime 
