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directions, others in which the solitary appendage has shown 
no sign of curvature, and some in which two appendages 
have existed at the same time, but separated by a larger 
angle than seems consistent with the meteorological theory. 
These instances, however, form the small exception and not 
the rule, and may, moreover, be explained as merely the 
results of perspective. 
I think I have now said sufficient to enable those who 
hear me to form an opinion as to whether the theory I have 
propounded is or not likely to prove a satisfactory explana- 
tion of some of the more striking of cometary phenomena. 
The theory is one which, as I take it, explains more and 
assumes less than is common with such theories. Besides 
those I have already named, there are other points which I 
conceive it fully to account for, but upon which it is quite 
impossible for me to touch in the brief space to which I 
feel I ought to confine my present remarks. There are 
points upon which I am of opinion that the application of 
quantities is practicable, and the theory itself I not only 
believe to be true, but the truth of it I conceive to be capable 
of numerical verification. To these and many other matters I 
hope to invite your attention on some other occasion, if you 
consider my present treatment of the subject as justifying 
any further expenditure of your time. 
