196 W. A. Norton on Molecular Physics. 
Toward what limit the series of numbers in column B would 
approach as the numer of observers increases indefinitely we 
cannot say. The uniformity of increase in the last part of the 
series is due, in part, to the fact that in dividing up the heavens 
among the observers, to each was left a comparatively unoccu- 
pied field. It seems probable, however, that the number would 
attain to, and even exceed, 2000, and hence that four persons 
do not see more than about half of the visible meteors. The 
ible. Let the observers look in different directions, so as t0 
. divide the heavens, as nearly as may be, symmetrically among 
them. Let the whole number of shooting stars seen be counted 
aloud to prevent duplication. At the same time, let each ob- 
server note how many are seen by himself. To prevent confu- 
sion this may be done by marking upon a card, the eyes mean: 
while not being turned from the heavens. 
Art. XXVII.—On Molecular Physics; by Prof. W. A. NoRT0™, 
[Concluded from p. 78.] 
its motion of rotation and its motion of translation through 
. 16). ccording to the most reliable determinations the 
veloped from the second cause must originate at of the 
sun’s surface that have a heliocentrie longitude of about 163°; 
and with a gradually decreasing intensity, on both sides of 
