92 



RESEARCHES CONCERNING THE PERIODICAL 



Table I. 

 Relative Second's Velocities of Meteors in Geographical Miles. 





Date. 



Designation, 

 of Meteor. 



Second's 

 velocity. 



Observer 



and 

 Computer. 



1798. 





a 



24. 



Brandes. 



a 





b 



18. 



(( 



1823. 





a 



20. 



it 



(( 





b 



24. 



(1 



(( 





c 



32. 



(( 



1824. 





a 



15. 



Quetelet. 



(< 





b 



22.8 



t( 



<( 





c 



13.5 



(< 



(( 





d 



9. 



a 



li 





e 



15. 



(i 



t> 





f 



10.2 



i( 



1833, 



November 12. 



a 



16. 



Twining. 



1836, 



November 13. 



abed 



average 



Boguslawski. 



1837, 



August 9. 



unknown 



average 



(( 



Mean second's velocity, 



18°^ .3 : 



t l"" .4 = 



1 .112 = 7 



Earth's 



> mean do., 



16"^ .45^ 



?9 = 



X 



The mean value of Table I. is farther confirmed, by considerations derived 

 from the mean duration and mean length of the visible paths of meteors. Mr. 

 Custodes*" found, from ninety-eight shooting stars, seen 9th August, 1837, at 

 Dusseldorf, that the mean duration of visibility was 1" 12.'" 7; that of twenty- 

 eight of the largest size 1" 45.'" 9 — none over 3." Benzenberg, from observa- 

 tions at various seasons of the year, concludes that the mean duration was 

 more than 1." These observations were made by means of a clock marking 

 thirds, (tertian-clock.) The length of the paths of the four meteors seen at 

 Breslaw and at a station in its vicinity, are given by Olbers.^* Also those 

 of ten coincidences at Vienna and Calvarienburg, August 29th, 1838, are 

 given by the younger Littrow,^^ both, as follows, in geographical miles of sixty 

 to a degree. 



1836, November 12, meteor a, visible path 5.96 miles. 



<( ( 



' b. 



24.88 



. (( 



' c, 



32.88 



(< 1 



' d. 



43.52 



1838, August 29, 



' a, 



12.28 



(( 



' b, 



29.28 



t( 



" c. 



17.20 



2* Schumacher's Jahrbuch, 1838, p. 324. " ijje,;^ p_ 3-22, note. «^ Annalen, &c. for 1838, p. xxi. 



