McGill College Observatory. 151 



winter months. Contiuued research may add a few species 

 to the list, and will enable us to speak more definitely with 

 regard to the time of arrival and departure of several 

 whose winter history has not yet been clearly worked out. 



SlJNSPOTS OBSERVED AT McGrlLL COLLEGE OBSER- 

 VATORY DURING THE Years 1888-89. 



By C. H. MoLeod. 



The accompanying table gives a summary of the obser- 

 vations of Sunspots made at McGill College Observatory 

 during the years 1888 and 1889. The spots were observed 

 by projection on a screen attached to a telescope of 6 in. 

 aperture ; the diameter of the sun's image being enlarged 

 to 8 inches. The heliographic latitude and longitude of 

 each spot at the time of observation, have been determined 

 with approximate accuracy. The dates given in the first 

 column, except January 1st, 1888, correspond with the coin- 

 cidence of the assumed prime meridian of the sun, with the 

 central meridian as defined in the "Observatory" ephemeris. 

 The numbers in the sixth column are obtained by 

 dividing the total number of single spot observations in a 

 rotation, by the number of days on which observations 

 were made during the rotation. 



A large spot, which was first observed near the eastern 

 limb on June 17th, 1889, (whole area about 10 oo ooo an( * 

 umbra to^VWo °^ tne 8Un ' 8 hemisphere) made one complete 

 revolution and was observed on its second rotation until it 

 disappeared bej^ond the western limb on July 24th. It did 

 not greatly alter in form or area while visible. A large 

 group, first seen on August 2nd, 1889, was observed in the 

 two following rotations and disappeared about the end of 

 September, having been last seen in longitude E 12° on 

 September 28th. On their re-appearance these groups have 

 been counted as " new." A small spot (area about 5 units) 

 was observed in the very high latitude S 40° on June 30th. 

 The observations were for the greater part made by Mr. E. 

 H. Hamilton, B.A.Sc, and the remainder by myself. 



