w 
THE 
LONDON, EDINBURGH, and DUBLIN 
PHILOSOPHICAL MAGAZINE 
AND 
JOURNAL OF SCIENCE. 
[SIXTH SERIES.] 
APRIL 1908. 
The following paper was written by Lord Kelvin some months 
before his death, and the subject with which it is concerned was 
occupying his attention down to the last few days of his life, in 
fact, till the commencement of his last illness. Very shortly before 
his death he wrote out in detail a paper on " Homer Lane's Problem," 
which he had communicated to the Royal Society of Edinburgh in 
January 1907, under the title "The Problem of a Spherical Gaseous 
Xebula " ; and it is proposed to reprint this paper, along with an 
appendix, written at Lord Kelvin's desire by his Private Secretary, 
Mr. George Green, in the next number of the Philosophical 
Magazine. 
The present paper has been carefully corrected by Mr. Green 
and myself, but it was left in a perfectly finished state, and little 
or no editing was necessary. — J. T. Bottomley. 
XL. On the Formation of Concrete Matter from Atomic 
Origins. By the late Lord Kelvin*. 
§ 1. /COALITION, due to gravitational attraction between 
\j materials given originally in small parts widely 
distributed through space, is probably the most ancient 
history of all the bodies in the universe. What the primitive 
forms or magnitudes of those pieces of matter may have been 
can never be made known to us by historical evidence. If 
they had been all globes, or irregular broken solids, of 
diameters a few kilometres, or a few thousandths of a milli- 
metre, and if among them all there existed all the atoms 
* Communicated by Dr. J. T. Bottomley, F.E.S. 
Phil Mag. Ser. 6. Vol. 15. No. 88. April 1908. 2 E 
