1879*] 
British Association. 
637 
any meaning, and such calculations are as futile as trying to 
count the drops in the ocean.” Mr. Crookes concluded his 
leCture by remarking that at length we seemed to have 
within our grasp and obedient to our control the little indi- 
visible particles which with good warrant are supposed to 
constitute the physical basis of the universe. We had seen 
that in some of its properties Radiant Matter was as material 
as the table, whilst in other properties it almost assumed 
the character of Radiant Energy. We had actually touched 
the border land where Matter and Force seem to merge into 
one another, the shadowy realm between Known and Un- 
known which for him had always had peculiar temptations. 
He ventured to think that the greatest scientific problems 
of the future would find their solution in this Border Land, 
and even beyond ; here, it seemed to him, lay Ultimate 
Realities, subtle, far-reaching, wonderful. 
The Mathematical and Physical Section was presided 
over by Mr. G. Johnstone Stoney, M.A., F.R.S. 
In his presidential address Mr. Stoney sought to show that in 
the study of mechanics and chemistry the two great methods of 
investigation, viz., the deduCtive and the experimental, could best 
be acquired, and that for a sound grasp of the remaining physical 
sciences, and especially with a view to further advance in 
physical science, a command of both methods of investigation 
is essential. He said that, in order to understand the present 
position of Natural Science upon the earth, w.e must remember 
that the universe is in itself one great whole, which includes 
minds no less than bodies, for thought is as much a phenomenon 
of what really exists as motion. But though the universe be 
but one, man with his limited powers is unable to treat it as 
such, but has to push his investigation of Nature when and 
where he can. Thus have arisen many sciences which were at 
first quite isolated. Their separate condition is a mark of the 
feebleness of our powers of investigation. Their gradual con- 
vergence, and especially where any complete contact: can be 
established between them, is the mark that our advancing know- 
ledge is penetrating deeper. 
In the present passing condition of our knowledge then there 
is one group of sciences which investigate the phenomena of 
consciousness; another distinct group of the biological sciences; 
and a third, the group of the physical sciences. These are all 
but parts of the one great investigation of Nature, but for the 
present they exist almost disconnected, as separate provinces of 
human inquiry. 
When we endeavour to investigate mental phenomena, we are 
