The Transit of Mercury on November 12, 1861. 



75 



shallower, till at last it could no longer be distinguished from 



the rippling outlines of the sun. I then looked at a watch (one 



however which has the failing of being generally two or three 



minutes slow), and 



the time marked was 



eight minutes to 



nine. 



And so the tran- 

 sit ended; the im- 

 pression on my mind 

 of a real movement 

 having been best 

 conveyed at its close, 

 as it then became 

 evident that the pla- 

 net was passing out 

 of sight. I thought 

 the planet showed 

 best as an unusual 

 object, about ten mi- 

 nutes before its dis- 

 appearance, that is lut> ' 4 ' 

 to say, shortly before its upper edge touched that of the sun. 

 The sun, through a telescope, always gives me the true impres- 

 sion of being a globe, not a disk. The solar spots as they come 

 into sight or recede from view by the sun's rotation, are always 

 foreshortened, as the engraved pattern, for instance, on a lamp- 

 shade would be. Close to the sun's edge they are extremely slight 

 and thin marks. But Mercury's shape, continuing unaltered, con- 

 trasted well with the solar spots. It was as though a small grain 

 of shot were suspended iu front of an illuminated lamp-shade. 



Fie. 6. 



Fic.fc 



Fig. 8. 



Mercury passing off the Sun's disk ; the movement being from right to left, in the 



direction of the arrow. 



The contrast to the solar spots was far less striking when 

 the planet was nearer to the centre of the disk. But, in truth, the 

 sight was altogether suggestive rather than striking, and was 

 not very truly characterized in a newspaper paragraph which 

 referred to it as "a grand phenomenon." 



