OBSERVATIONS OF LUNAR OBJECTS. 



61 



the curves in fig. 1 have been projected. The first curve is that of solar 

 altitudes at the moon, epoch the equinoxes, locality 50° north or south lati- 

 tude. The second curve is that of the mean number of spots visible during 

 each interval. 



Fig. 1. 



1 3 .5 7 9 11 13 l.=i 17 19 21 23 2.5 27 29 31 



No. 1 0' 



No. 2 0' 



3 5 7 a ii Id io ii ly 21 iij 2o zi zy 

 Curve No. 1. Solar altitudes. Latitude 50° at equinoxes. 

 Curve No. 2. Curve of mean number of spots visible each interval. 



0° No. 1 



0" No. 2. 



