156 



TENTH ANNUAL REPORT OP 



made by Mr. E. P. Greg, jr., to wliicli I would refer all tliose specially- 

 interested in this subject. It is to be found in the Lond. Phil. Mag. 

 for 1854. 



A fact of much interest is that the number of meteorites already 

 discovered in the United States is quite large, and, contrary to the 

 general rule, the iron masses are the most numerous. The following 

 table, by Mr. Greg, jr., shows at a glance the number of meteorites 

 already found in different countries, the proportions of the stones and 

 irons, and the average latitude of their localities, 



The number of these bodies which fall annually cannot be well 

 determined. In the last sixty years the average falls observed are 

 ten per annum ; but of course the actual number must have far ex- 

 ceeded this, and some authors have supposed that not less than five 

 hundred must fall annually on various parts of the surface of the 

 globe. 



In this lecture our object is not to enter into a detailed account of 

 all the peculiarities of appearance of meteoric stones, either while 

 falling or after their descent. The more immediate object is to 

 consider the probable origin of these bodies ; yet it is of general in- 

 terest to mention some of those peculiarities before proceeding to the 

 theoretical discussion. 



Meteoric stones^ as they fall, frequently exhibit light ; are sometimes 

 accompanied by a noise, and occasionally burst into several fragments. 

 All of these phenomena are produced after they enter our atmo- 



