112 Oil the ProbabiUhj of Meleoroliles 



sideiable, with a concentration of light greatly exceeding any 

 thing of the kind we had ever before witnessed. It is impossible 

 for words to do adequate justice to the excellence of this instru- 

 ment. It was constructed hy Mr. Crickman, of this town, a 

 self-taught optician, who has for some time past been highly re- 

 ported of, for the perfect manner in which he makes his specula 

 — particularly the finishing part of giving an exquisite polish, and 

 forming the most desirable and difficult to be obtained figure; — 

 as he has also been for making very superior microscopes. He 

 has manufactured for me one of each sort at a reasonal)le rate, 

 with which I am entirely satisfied. His rare abilities are well 

 known to Major Kater, and several other scientific gentlemen, 

 who have employed and approved him. — I shall be much obliged 

 by your naming him in your Magazine, as soon as a convenient 

 opportunity offers. 



The dark dense cloud near the Sword of Orion was seen by us 

 to great advantage by the above telescope, as also a group of 

 spots near the centre of the sun's disk by Mr. Lofft. 



Mr. Capel Lofft to Mr. Acton. 



Ipswich, Dec. 30, 181?. 



Dear Sir, — I have been thinking of our conversation last 

 night respecting meteoric projectiles. 



Yours of the 8th at any rate we may safely sav could not be 

 from the moon, it being then new moon (within less than twelve 

 hours after) and the moon consequently near one-third of our 

 earth's circumferential rotation below our horizon, and the vi- 

 sible path of the meteor from west to east ; in order to which it 

 must have traversed a vast portion of the lower sky beneath our 

 •earth, corresponding to near IGOOO miles of the earth's circum- 

 ference, before it would emerge above our horizon in the west- 

 ward. 



But wc may consider the supposition generally. 



The moon is about thirty of our diameters distant from us, 

 and we must appear at the moon a diameter of about two degrees. 

 Mow at the radius of 240,000, what probability is there of a pro- 

 jectile being thrown from the moon, to a point of a circum- 

 ference at this distance from her sufficiently near our positvou 

 at the time to bring it to the earth, and prevent its falling back 

 to the moon again ? 



It has an equal probability of being thrown to the side further 

 from the earth, or at right angles to the earth, or at some other 

 angle less than a right, but too great to admit of its falling to 

 the earth: — the circumference on such a radius being about 

 1,500,000. 



If projected from the moon so as to approach the earth at an 



angle 



