262 THE METEOR OF JULY 13tH, 1846. 



was heard. As this was noticed by a considerable number of persong, 

 and in places so remote from each other it is scarcely possible they 

 could have been mistaken. As might be expected, their estimates of the 

 interval which elapsed were difierent; but an intelligent gentleman, who 

 was paying particular attention in expectation of a report, states that it 

 was at least six minutes. This would indicate a distance of about 70 

 miles at the time of the explosion. But here we are met by the ques- 

 tion, whether a sound originating at so great an elevation from the earth 

 could reach its surface. Jt is well known that the intensity of sound 

 depends upon the density of the air by which it is conveyed. The dis- 

 tance at which the report of a pistol can be heard upon the summit of 

 a lofty mountain is much less than if fixed upon the plain below. The 

 collision of solid substances, as the ringing of a bell in an exhausted 

 receiver, produces no sensible impression upon the ear; and as the rare- 

 faction of the atmosphere at the height of 60 miles is much greater than 

 that which we can produce by the air-pump, it is manifest that a sound 

 originating at that elevation, to be heard by us, must have an exciting 

 cause inconceivably greater than any with which we are acquainted. 

 This was doubtless the case in the present instance, if we consider the 

 size and immense velocity of the meteor. There are, moreover, un- 

 doubted instances on record of meteoric explosions at even greater alti- 

 tudes being distinctly heard. The great meteor seen in England, March 

 19th, 1719, was about 70 miles from the earth's surface at the time of 

 its explosion. The report, notwithstanding, was like that of a broad- 

 side, and so great was the concussion that the windows of houses were 

 violently shaken. Tt has, however, been suggested " that at these enor- 

 mous heiglits sound may owe its propagation to some other medium 

 more rare and elastic than air, and extending beyond the limits of the 

 atmosphere of air and vapor." 



THE METEOR CO.NTINLED. 



In connection with the preceding valuable communication, we publish the following extract of 

 a letter from a scientific correspondent. Our readers will perceive that the data, upon which the 

 notice of the meteor in our last number was based, were imperfect. But as that notice has elicited 

 more definite and valuable information from abroad, than we were able otherwise to obtain, it has 

 done a good ser\'ice. We heartily concur in the concluding suggestion of our correspondent. 



New Haven, Conn., Aug. 8, 1846. 



* * * In the ''Literary Record and Journal of the Linnaean Associa- 

 tion of Penua. College," Aug. 1846, 1 notice some account of the splen- 

 did meteor of the 13lh ult. This body was also seen by several per- 

 sons in New Haven, and tolerably well observed. The observations 



