Sun Viewing and Drawing. 435 



Before proceeding- to describe the method of measuring 

 the spots, or other solar phenomena, it may be well to refer the 

 reader to the Plate accompanying this paper, wherein may be 

 seen micrometric drawings of various solar spots, the first 

 four figures of which show the precise size and general appear- 

 ance they presented on the screen (save that the attendant 

 faculae are omitted), and as they were then and there depicted. 

 The two last figures were originally viewed and drawn under 

 optical appliances of double power, and have been consequently 

 reduced one half, linear, in order that the same scale might 

 serve for all alike, viz., about 27,000 English miles to the inch ; 

 or, astronomically speaking, on this same scale one minute of 

 celestial arc subtends one inch, and every second of this minute 

 measures about 450 English miles near the centre of the disc, 

 where the effects of foreshortening, produced by viewing 

 objects on the surface of a sphere, are reduced to the minimum. 



Sir John Herschel has alluded* to the bizarre, and even 

 grotesque appearance assumed at times by the solar spots. 

 And truly this circumstance with regard to them is occasionally 

 not a little remarkable ; and before describing more particularly 

 the phenomena whicli frequently characterize an ordinary and 

 well developed spot, we would call attention to Figs. 5 and 6 in 

 the Plate, wherein Fig. 5 (which is not in the slightest degree 

 exaggerated in form and symmetry) will probably be allowed 

 to bear a very close resemblance to the petal of a geranium, or 

 perhaps, picotee, or other flowering plant, according to fancy ; 

 whilst Fig. 6, affected, it is true, by a high degree of fore- 

 shortening, the most advanced border of the spot being not 

 more than ten seconds from the preceding limb of the sun, 

 may suggest to a lively imagination the belief that the uncouth 

 gallinaceous bird, Didus ineptus (the Foolish Dodo), though 

 said to be now extinct as a terrestrial species, is still to be 

 reckoned among the fauna of the sun ! By such comparisons, 

 at any rate, may the mind be diverted occasionally, if only the 

 whim be not allowed to warp the hand, whilst studiously trans- 

 ferring a representation of the solar spots from the screen to . 

 the sketch-book. 



The writer has preferred to delineate this case of Didus 

 ineptas as an instance of the grotesque, rather than another 

 one still more remarkable, simply because it so happens that a 

 photographic record of the occurrence of that rara avis was 

 secured by Mr. John Titterton, of Ely, for Professor Selwyn, 

 and to which, therefore, some of the readers of the Intellectual 

 Observer may be able, perhaps, to refer, though they must be 

 reminded that the photographs represent the solar image and 



* Sec Herschel on the Solar Spots, Quarterly Journal of Science, No. II., 

 p. 224. 



