190 MR. JOSEPH BAXENDELL ON THE 



present state of the inquiry I am not prepared to enter 

 into any theoretical explanation of this remarkable pheno- 

 menon. My observations have hitherto been made without 

 reference to any particular theory, and they have led me 

 to believe that much yet remains to be done in accumu- 

 lating the raw materials of observation before we can 

 obtain results sufficiently well established to form the 

 basis of a philosophical theory of solar phenomena; and 

 at present I do not offer the conclusions given in this 

 communication as anything more than the first results of 

 an attempt to pursue, without reference to any theory, a 

 systematic examination of the phenomena of the solar spots. 



The following extracts from my journal of observations 

 will serve to illustrate the several points to which I have 

 drawn attention. Greek and Roman letters are used to 

 denote the different spots and groups as laid down in 

 diagrams in the journal; and I have often found it conve- 

 nient to indicate the size of spots by reference to a scale 

 of magnitudes, in which the first magnitude represents a 

 spot of the largest size and the tenth one of the smallest. 

 The telescopes which have been used in the observations 

 are a small but excellent achromatic by Mr. Dancer of 

 twenty-two inches focal length and 2*6 inches aperture; a 

 Newtonian reflector of eighty inches focal length and 

 seven inches aperture; and the excellent equatorially- 

 mounted achromatic of Mr. Worthiugton's observatory, 

 which has a focal length of seventy inches and an aperture 

 of five inches. 



Observations. 



September 9, 18^9, gh. a.m. Of the siic groups now 

 visible on the sun's disc, five have their largest spots in the 

 preceding part of the group, and the sixth consists of spots 

 differing little in size. 



September 22, 5A. p.m. The sun has gone through 

 half a revolution since the observation of the gth instant, 



