146 
of certain comets and certain meteoric streams is a 
matter of too serious moment to be passed over without 
attention by a cometaiy theorist. The physical connection 
which it indicates is one to be accounted for. It may be, 
firstly, that meteors are the uncollected elements or particles 
from which comets are built up, or secondly, that meteor 
streams and comets are identical,^ or thirdly, that by disin- 
tegration and dispersion the constituents of a comet have 
become a meteor stream. 
So far as I have found no evidence has been adduced that 
comets aggregate material in their journeys round the sun 
whilst their supposed identity with meteor streams is merely 
an hypothesis built upon no observation and failing to 
explain with clearness any of their distinguishing pheno- 
mena. There is however evidence enough that sub-division 
is not uncommon amongst bodies of the cometic class.*[* 
Bi-partition is recorded in the Chinese annals four centuries 
before the birth of Christ, whilst of modern evidences of 
disintegration the separation of Biela’s comet into two in 
1846 places the phenomena of sub-division beyond the 
reach of doubt. The fact of Biela’s total loss and the exist- 
ence of a meteor stream along its former path seem to 
establish complete disintregation as a known result and a 
meteor stream as an observed effect. During the apparition 
of Donati’s comet in 1858 an appearance was remarked in 
connection with the tail which Bond considered due to a 
quantity of scattered and abandoned gas.j But according 
to that theory which it is the object of this pa.per to advance 
the disintegration of cometic bodies is not a matter for 
surprise. For considering the enormous distances to which 
according to that theory some portion of the cometic matter 
is removed aud the manner in which it is dispersed it is 
See “Nature,” vol. 4, p. 268. 
t See “Kirkwood on DisintegTation.” Nature, vol. 6> p. 148, 
X “Annals Harvard College,” vol. 3, p. 158 — 60. 
