414 H. A. Newton— Biela Meteors of Nov. 27th, 1885. 



57,300 k. for the meteoroid's relative velocity per hour. The 

 space in the meteoroid group corresponding to each single visible 

 meteor was therefore, in the densest portion of the group, a cube 

 whose edge in kilometers is the cube root of 57,300;r/5*l, that is, 

 32'8 kilometers, or 20'4 miles. 



Thickness of the stream of meteors. — As the earth has a 

 velocity of 18*5 miles a second and its orbit has an inclination 

 to the stream of 12° 33 ; , the earth's motion perpendicularly to 

 the stream is 14,500 miles per hour, or 87,000 miles in six 

 hours. The really dense portion of the stream was then less 

 than 100,000 in breadth and nearly all of it was included in a 

 belt 200,000 miles in thickness. One hundred thousand miles 

 subtends at the sun an angle of 3'"7. 



Radiant of the meteors. — Nearly every observer paid special 

 attention to the radiant, so that perhaps at no previous time 

 has there been so generally an effort to determine its position 

 accuratel} 7 as in the present shower. The result is correspond- 

 ingly instructive. I have collected in the following table a 

 considerable number of places assigned for the radiant, apply- 

 ing in a few cases a correction for precession to reduce from 

 the date of the chart to the equinox of 1885*0. With some of 

 these there is given the hour of the evening to which the radi- 

 ant belongs, but the larger part are without such an indication. 

 Five of them reported by Mr. Denning, at Bristol, are for 

 preceding and following evenings. About seven-eighths of these 

 tabular places are represented in the accompanying figure, p. 

 417, the remaining places being beyond its limit. The Pulkowa 

 observations are plotted with R. A. 25° -5. 



Place. 



Observer. 



E. A. 



Dec. 



Agra, _ 



Strahan, 



26°'2 



46° 



Mauritius, 





near 



y Andr 



Bey rout, 



West, 



25-5 



43-5 



Athens, 



Lephay, 



21 



32 



Pulkowa, 



Romberg, 



24-27 



44 



u 



Backlund, etc., 



24-27 



46 



it 



H. Struve, 



24-27 



48 



a 



O. Struve, etc., 



24-27 



50 



u 



L. Struve, etc., 



22 



53 



ce 



a 



24 



44 



Upsala, 



Gyllenskiold, 



23-7 



44-4 



cc 



c« 



22-3 



44-2 



a 



cc 



21-0 



44-2 



a 



cc 



25*6 



45-9 



a 



Fin eman, 



22-6 



41-5 



cc 



« 



22-15 



44-9 



cc 



k 



21-65 



45-4 



cc 



Charlier, 



23-4 



45-0 



cc 



tt 



24-6 



45-5 



