26 



SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. (^ 



views I have investigated very various material and I submit the 

 most important results in the following tables i, 2, 3, 4, with the pre- 

 liminary remark that the groups, under tables i and 2, relate princi- 

 pally to small phenomena (star showers), but those under tables 3 

 and 4 relate principally to fire balls. 



Table i (Note i). 



Limiting altitudes 



Above 100 km. 

 80-100 " 

 60- 80 " 

 30- 60 " 



below 30 " 



No. of cases 



48 



33 



17 



2 



Average observed 

 geocentric velocity 



(i^.^ km. 

 51.5 " 



35.5 " 



30.1 " 



23.2 " 



Average ter- 

 minal altitude 



106.6 km. 



73-0 

 46.2 

 28.8 



Table 2 (Note 2). 



Above 100 km. 

 80-100 " 

 60- 80 " 

 50- 60 " 



below 50 " 



Above 60 km. 

 50- 60 " 

 30- 50 " 



below 30 " 



10 

 II 



13 



6 



14 



72.3 km. 

 43.0 " 

 40.5 " 



35.4 " 

 27.4 " 



Table 3 (Note 3). 



12 ( I deton.) 51.8 km. 



19 ( 3 deton.) 5S.O " 



43 (16 deton.) 40.6 " 



28 (13 deton.) ZTJS " 



^ The cases under i are taken from the above mentioned " Memoirs of the 

 Br. Assoc." (Foot-note 3, p. 25). 78% of them are shooting-stars, 11% meteors 

 from one to four times the magnitude of Venus, 11% fire balls up to the 

 magnitude of the moon without records of detonations. 



" 2 refers to the older work published by Denning (W. F. Denning, " 107 

 Real paths of Fireballs and Shooting-stars observed in England from 1886 

 to 1896." Lond. Astr. Soc. Monthly Not. 57, p. 161) wherein 74% are 

 shooting-stars, as above, 6% meteors of the magnitude of Venus or somewhat 

 more, 20% fire balls including one which detonated. 



^3 is taken from a list of mostly very large meteors which I pubHshed in 

 the same number of the Monthly Notices, p. 170. Of the 100 cases given there 

 the velocity could not always be determined ; with later additions they gave, 

 however, 102 coherent determinations of the terminal altitude and velocity. 

 This material contains only 8% of shooting-stars of from the first to the fourth 

 magnitude, 27% meteors from one to several times the magnitude of Venus, 

 while 65% are large fire balls comparable in magnitude with the moon or sun, 

 of these 30% detonated and seven were accompanied by a fall of a meteorite. 



