396 ANNUAL OF SCIENTIFIC DISCOVERY. 



Mr. Hartnup and Dr. Mann noticed that the line-like segment of the 

 planet's disc was broken up into three or four beads of light, just before it 

 finally disappeared behind the moon. This result was due to small projec- 

 tions of the moon's border crossing the streak of light in some places, while 

 portions of the streak were still visible at indentations of the lunar edge in 

 others. Mr. Hartnup saw the third satellite of the planet shining in the midst 

 of a large indentation of this kind for a second or two, and looking as if 

 within the circumference of the lunar face. Professor Challis, employing 

 the great Northumberland refractor at Cambridge, noticed that the moon's 

 dark limb, as it SAvept in front of the bright planetary surface, was dis- 

 tinctly jagged and zigzagged by valleys and mountain-peaks. 



As the planet slipped out from behind the bright side of the half-illumed 

 six-day-old moon, the different characters of the planetary and lunar light 

 were strikingly apparent. The planet's face was about as pale again as the 

 moon's, and seemed to most of the observers watching it to wear, as com- 

 pared with the moon's aspect, a soft greenish hue. Mr. Lassell was of 

 opinion that the planetary faintness was mainly the result of the relatively 

 large brilliant surface the moon presented in such close proximity ; he 

 believed that there would not have seemed anything like so marked a differ- 

 ence of intensity, if the planet had been contemplated in contact with a 

 piece of the moon, having dimensions not larger than itself. 



But the most interesting fact yet remains to be told. The bright border 

 of the moon at this time crossed the soft green face of the planet, not with 

 a clear, sharply cut outline like that which had been presented as the disc 

 passed into concealment ; it was fringed by a streak or band of graduated 

 shadow, commencing at the moon's edge as a deep-black line, and being 

 then stippled off outwardly until it dissolved away in the green light of the 

 planet's face. This shade-band was about a tenth part of the planet's disc 

 broad, and of equal breadth from end to end. Mr. Lassell described it as 

 offering to his practised eye precisely the same appearance that the obscure 

 ring of Saturn presents to a higher magnifying power, where that appendage 

 crosses in front of the body of the Saturnian sphere. 



There could be no mistake concerning the actual existence of this 

 curious and unexpected apparition. It was independently noticed and 

 described by at least six trustworthy observers, and the descriptions of it 

 given by each of these corresponded with the minutest accuracy. The sha- 

 dow was seen and described by Mr. Lassell, at Liverpool ; by the Rev. Pro- 

 fessor Challis, at the observatory at Cambridge ; by the Rev. W. R. Dawes, 

 at Wateringbury ; by Dr. Mann and Captain Swingburae, R. N., at Vent- 

 nor ; and by Mr. William Simms, at Carshalton. It therefore only needs 

 that the unusual presence should be accounted for ; the handwriting being 

 there, the question remains to be answered ; " Can its interpretation be 

 found ? ' Can science read the meaning of this shadow-fringe inscription ? 

 Are there minds that can fathom, as well as eves that could catch, this 



tt 



signal-hint thrown out by Jupiter at the instant of its emergence from its 

 forced concealment behind the moon ? 



It was Mr. Dawes's impression on the instant, that the mysterious shadow 



