THE SUN'S SPOTS. 399 



" I observed large spots visible to the naked eye in almost 

 all the years not characterized by the minimum ; the largest 

 appeared in 1828, 1829, 1831, 1836, 1837, 1838, 1839, 1847, 

 1848. I regard all spots whose diameter exceeds 50" as 

 large, and it is only when of such a size that they begin to 

 be visible to even the keenest unaided sight. 



"The spots are undoubtedly closely connected with the 

 formation of facula?, for I have often observed faculae or ' nar- 

 ben' formed at the same points from whence the spots had 

 disappeared, whilst new solar spots were also developed within 

 the faculae. Every spot is surrounded with a more or less 

 bright luminous cloud. I do not think that the spots exert any 

 influence on the annual temperature. I register the height 

 of the barometer and thermometer three times in the course 

 of each day, but the annual mean numbers deduced from 

 these observations have not hitherto indicated any appre- 

 ciable connection between the temperature and the number 

 of the spots. Nor, indeed, would any importance be due to 

 the apparent indication of such a connection in individual 

 eases, unless the results were found to correspond with others 

 derived from many different parts of the Earth. If the 

 solar spots exert any slight influence on our atmosphere, my 

 tables would, perhaps, rather tend to show that the years 

 which exhibit a larger number of spots, had a smaller number 

 of fine days than those exhibiting few spots." (Schum. 

 Astron. Nachr. No. 638, 221.) 



" William Herschel named the brighter streaks of light 

 which are seen only towards the Sun's circumference, facula, 

 and the vein-like streaks visible only towards the centre of the 

 Sun's disc, ' narben' (Astr. Nachr. No. 350, p. 243). I am 

 opinion that the faculce and 'narben' are both derived from 

 the same conglobate luminous clouds, which appear more 

 intensely bright at the circumference, but being less luminous 

 in the centre of the Sun's disc than the surface, exhibit the 



