The Express.
London, England, 1850-08-05 00:00:00

THE BRITISH ASSOCIATION.

EDINBURGH, SATURDAY.
Yesterday, the sections met in great form, with a
most istereotiag programme of bushier in several el them.
In the Geological Section, which is tte most numerously
attended of all the endow, there were a number of valuable
papers read, all of whisk had • reforests to the glacial
theory.
kr. Boußn? CHAWBIU contributed a paper on the geo-
logical phenomena around Edinburgh ; In the course of
tithish he remarked that throughout the valley of the Forth,
from the Pestles& on the one side to the Fife hills on the
other, from Linlithgow to Barber, the sandstone surface*,
wherever they come up, are likewise smoothed, and in many
instances iterated, the stein all pointing to the E N.E., it
thereby. The trap bills rising in this valley are all long and
narrow, generally free from abruptness on the sides, often
abraded on the west, and generally sloping away gently to
the vet ; the direction hers also is always to E N.B. Bra-
frees on the Nintendo and in Fife exhibit striation precisely
osoforniable. Its short, if • deep ice-flow paned through this
valley, Weight be expected to produce precisely the pheno-
=se whk.khays been observed.

Mr. H. liria.za read a communication on peculiar
scratched pebbles and fold' specimens from the boulder
clay, end on chalk flints and Oolitic lasi!' from the boulder
slay in Caithness.
A number of o•her espies were real by Mr. Macloran,
Mr. Hopkins, the Rev. Mr. Longintdr, &a., and a long dis-
suasion took place, which was participated in by Sir R. I.
Murchison, Professor James Forbes, Mr. Smith, of Jordon-
hill, Professor Hitchcock, of America, Dr. Martins, from
Paris, &e.
In the Mechanical and Physical Section, Sir D►vid Brews-
ter gave a short notice on the polarising structure of the eye.
He referred to the phenomenon called Haidirges'a brushes.
Tune discoveries prove three different polarising structures
in the eye—la fact, that the eye may be a polariscope. It
was difficult to see the brushes. Neither he nor Heedieger
oar explain the cause of this property.
Prole/see Stokes had also a communication on the same
subject. He had seen the brushes with great faciiity ; and
he described their appearances as seen under various circum-
stanees, and at various positions of the spectrum, having
traced them over several of Fraunhofer's lines.

Mr. Clark Maxwell described sonoexpeTiments on the
same subjece, which give rise to an later's:jog conversation
between himself. Sir D. Browder, and Messrs. Airey and
Stokes.

In the Natural History S ration, a paper was read by Mr.
H. B. fkrickland, F.L.B , and Dr. Danbeny, being a report
on the Vitality of Seeds. The report stated that the aside
had been arranged into their natural families, and sown in
the Botanic Garden at Ont rd. It was found that some lost
their vitality after two years. The grasses retained vitality
for a very long period, and in otter vegetables it was dia.
covered that the seeds of different families of plants retained
their vitality for various periods. The experiments had
embreoed seeds kept from 10 to 20 years, from 20 to 29,,fr0m
30 to 39, and eves above 40. There was a vulgar not!on
that Wheat had been found in an Egyptian m..mmy, and
afterward. grown f• this country. From ell the negative
evidence he could collect, for the evidence wu all negative,
he could not discover the slightest truth for this statement.
In the Chemical Section, Dr. Lyon Elayfairritad a papar on
the condensation of volume in highly hydrated minerals.
This paper went on to explain a very remarkable law, in
virtue of which it appears that in many solid bodies which
captain water such a condensation occurs, that they occupy
no greater space then the water in them does if frozen into
ice.

Professor Williamson, of the University College, London,
also hid before this se:llion a very ingenious thtory on the
production of ether, which led to a good deal of dicussicn.
In the evening there was a conversation and promenade in
the Music Hall, which was most brilliantly attended.
Thh d►y (Saturday), wee, u utuol, devoted to excursions
—one to the Bass Rock, and anothtr to the Pentland Hill&