446 Chronicles of Science. [July, 



of aerolites, it has been found from a microscopic examination of the 

 mixed minerals of which they consist, that their crystals differ in some 

 essential particulars from those of ordinary volcanic rocks, but their 

 consolidation must have taken place from fusion in masses of moun- 

 tain size. The planetary velocity (at least 15 miles per second) of 

 the meteor, which produced the recent aerolites of Orgueil, greatly ex- 

 ceeds the ballistic forces which can be supposed to reside on the sur- 

 face of the earth or moon. We are therefore compelled to give a 

 wider range to conjecture with regard to aerolites, and to suppose 

 that they are projected from small planets near and. within the orbit 

 of the earth. Aerolites commonly fall in the daytime. They circulate 

 round the sun in such countless numbers, or else they bear such 

 close a relationship to the earth that they in all probability strike the 

 earth daily in its path. 



Mr. A. S. Herschel has also contributed an elaborate article on 

 the " Eadiant Points of Shooting Stars." We regret that it would be 

 impossible to condense this article so as to give a good idea of the 

 results at which the author has arrived. 



The next paper was by J. Joynson, Esq., " On the Appearance of 

 Mars." This subject has been so ably treated in the former part of 

 this number by Professor Phillips, that no further mention of it is 

 required here. 



The Number of the ' Monthly Notices,' which contains a report 

 of the March Meeting of the Society, is illustrated with a Photo- 

 engraving of a Lunar Photograph, printed from a plate untouched by 

 the graver. The picture, one of the most successful of its kind we have 

 ever seen, has been taken by Paul Pretsch's process ; but the original 

 negative is apparently so perfect, that it is a matter for regret that Mr. 

 Fox Talbot's photoglyphic process had not been adopted as a means 

 of multiplication, as by this scarcely any of the fine definition would 

 have been lost. It will be evident that by a process of this kind we 

 have at our command a means of procuring prints of the lunar or 

 solar surface, having all the permanence of ordinary engravings ; and 

 these methods, if used to reproduce photographs of large dimensions 

 (thirty-eight inches in diameter, for example), would give such re- 

 liable charts as with any other mode of procedure it would be im- 

 possible to obtain. Much of the half tint is lost ; but, nevertheless, 

 so much of value is retained as to show that some such process is 

 deserving of more general adoption for scientific objects than it has 

 hitherto received. 



At the conclusion of the meeting, Admiral Manners, who occupied 

 the chair in the absence of the president, remarked upon the present 

 activity and good condition of the Society. The communications are 

 very varied in their character ; the general range of the papers pre- 

 sented shows that observers and those who communicate their obser- 

 vations to the Society, are alert and alive to the importance of quick 

 and rapid communication to this centre of astronomical science. It 



