172 
ions, and each of them will represent Jupiter's place at monthly 
intervals. Starting with any one of the positions of the Earth as 
January, name the next one February, the next March, and so on, in 
the direction from right to left, or the reverse way that the hands of a 
clock travel over its face. Do. the same for the montlhy places of Jupiter, 
and finally connect by straight lines the points of the same name in the 
two circles. The point on the smaller circle represents the station of 
the observer for that month, and the point on the larger circle is 
Jupiter's actual place for the same month. The line joining these points 
is the line of vision, and if it be prolonged beyond the larger circle to a 
considerable distance the farther the better an arc may be drawn 
there which will represent a portion of the region of the stars, an arc of 
the ecliptic. On extending all the lines to this arc in the order of the 
months, it will oe found that they intersect and retrograde exactly as 
does the planet when followed by actual observation in the heavens ; 
and the more accurately that the diagram is drawn to scale, the more 
exactly will the figures explain Jupiter's actual motion. Nothing can be 
more interesting or more instructive to a beginner, than the combination 
of actual observation of the planet, with a geometrical plotting of the 
motions on paper in this way. 
/ 
NOTICE TO MEMBERS. 
This number makes eleven issues of the Naturalist and com- 
pletes the Volume of 178 pages, besides the 24 pages of Flora Ottawa- 
ensis issued during the year. 
The Annual Meeting will beheld in the Normal School on Tues- 
day, March 20th, at 4 15 p.m. and in the interest of the Club a large 
attendance is desired. Those who have not paid their subscriptions 
for the year will kindly forward the same to the Treasurer without delay 
6IC 
"V, 
