74 Proceedings of the Royal Society of Edinburgh [Sess. 
group, revolving round the sun with them and circulating between them 
in complicated changing volutes. In the course of these motions such 
bodies would from time to time strike the earth. That is where I suppose 
our meteorite to have come from. 
[Note added March 4, 1918. — The ascription of meteorites to lunar 
volcanoes is an old one. It appears to have been first made in 1660 by 
an Italian, Terzago. After Biot’s demonstration that the meteorite which 
fell at 1’Aigle was an unquestionable case of a body falling from the 
sky, the cosmical character of these bodies was canvassed actively. 
Laplace made the suggestion of a lunar origin without committing 
himself to it, and it was favoured also by Biot, Poisson, and Arago. 
At that period, on W. Herschel’s authority, the existence of active volcanoes 
on the moon was not discredited. If we are to hold to a lunar origin 
at the present day, we must suppose the meteorite to have circulated from 
a remote past between the earth and moon without falling upon either. 
This is quite possible. The body need not possess anything like a regular 
or periodic orbit, and if it once belonged to the earth-moon system, it 
might continue to do so indefinitely, until its motion was terminated by 
collision.] 
{Issued separately May 29 , 1918 .) 
