442 
needed until about sun-rise, when the 
other cock is shut off, and this clock lan- 
tern extinguished, in its turn, with those in 
the adjacent street. The lantern is cu- 
riously glazed, conyexly, in five panes; and 
a number of plane mirrors are, concavely, 
fixed behind the burner, to act as a reflector 
in throwing the light principally on the 
clock-face. In the supporting gas-pipes, 
above-mentioned, there are air-tight hinges, 
which admit the lantern being moyed by 
help of the chains, and brought within reach 
of the person at a window of the steeple, 
who daily cleans the mirror and- glass front 
of the lantern. 
Acceleration of Water-wheels. —“ This fact 
(is it fully substantiated?) is well known to 
most persons who have been connected 
with mills. The workmen attribute it to 
the moon—probably from its supposed in- 
fluence upon the tides. But it is, perhaps, 
owing to the pressure of the atmosphere 
during the night—the earth and circum- 
ambient air being rarified during the day ; 
the colder air above, upon the going down 
of the sun, condenses, and passes towards 
the earth. The assertion should, there- 
fore, have been made with a little modifi- 
cation—not that every night a mill (water- 
wheel) goes faster than during the day; 
but upon such nights, and during such 
Praceedings of Learned Societies: 
{June I, 
weather, as to produce additional atmo- 
spheric pressure.” Another writer says, 
“1 live in the vicinity of numerons saw- 
mills, and it is, here, the universal belief 
that these mills move faster in the night than 
in the day, and that more work may be 
effected, in a given time, durmg the former 
period.’ More than a year since, I was. 
Jed to. perform some experiments, the re- 
sult of which is, that they do not move more 
rapidly in the night than in the day.— 
Prof: Silliman’s American Journal of Arts 
and Sciences. 
Expansion of Ice, —That iee expands from 
the centre of the pond, or vessel, towards 
the edge is evident ; for when water freezes 
in an earthen, or even metal, vessel, the 
expansion, from the middle to the sides, is 
so strong as to break it, if due care be not 
taken, When an egg is frozen it. will 
burst; and sometimes, also, trees haye 
split from the same cause. ‘The. precise 
nature of the change produced on air by 
excess of heat, is not, perhaps, thoroughly 
understood ; but it is supposed, that a par- 
tial combustion of animal and vegetable 
matter takes place: it, however, produces 
a yery sensible effect on any person, re- 
maining a considerable time in. air that bas 
undergone this change. 
PROCEEDINGS OF LEARNED SOCIETIES. 
—>—— 
ROYAL SOCIETY. 
PRIL 14,—The reading of “ A Mo- 
nograph on Egyptian Mummies, with 
Observations on the Art of Embalming 
among the Ancient Egyptians,’’ was com- 
menced by A. B. Granville, M.D., F.R-S. ; 
and on the 2Ist and 28th the paper was 
continued and concluded. 
LINNZAN SOCIETY. 
On the 5th of April, a valuable present 
of stuffed birds and fishes was. received 
from Captain King, collected by him in 
his. late expedition to explore the North- 
west. Coast of New Holland; a farther 
portion. of Dr. Hamilton’s “Commentary. 
on the Hortus Malabaricus,” was also read; 
and on the 19th, a continuation of the Rey. 
Messrs. Sheppard and Whittear’s paper on 
* Norfolk and Suffolk Birds,” was read. 
GEOLOGICAL SOCIETY. 
On the 18th of March, the paper en- 
titled ‘‘ Observations on the Beds of Clay, 
Sand, and Gravel, belonging to the Red 
Marl Formation of the Midland Counties, 
‘and on the Rocks from which they are de- 
rived,” by the. Rey. J. Yates, M.c.s., was 
eoncluded. Mr. Yates enters into some 
description of the rocks which are found in 
situ on the confines of Wales and Shrop- 
shire, in order to shew that from the disin- 
tegration of these rocks, the clay, sand, 
and gravel of the red marl formation have, 
for the most part, been derived. He, then 
proceeds to shew how the strata, belong- 
ing to the older formations. which he has 
described, may be. viewed in connexion 
with the general physical structure. of Eng- 
land; and then points out, from what va~ 
rious sources the beds of sand, clay, and 
gravel of the red marl formation, as well 
as the superficial debris which is strewed 
over the midland districts of England, may 
have originated. He concludes with some 
remarks on the excavation of vallies, and 
on some opinions on that subject, now 
generally received among English geolo- 
gist, from which he is inclined to differ. 
April 15th.——A paper was read, en- 
titled,. “‘ On, a new. species. of. Gyrogonite 
from. the lower. Fresh-water Formation at 
Whitecliff Bay, in the Isle of, Wight, with 
some Account of the Strata in which, it 
occurs,” by Charles Lyell, Esq., See. Gs. 
This species of gyrogonite is described as 
very distinct from the three species found 
in France. The spiral valyes form. nine 
rings, each of which is ornamented with a 
row of tubercles; wherefore he has given 
the name of chara tuberculata, Amnaccount 
is given of the, strata of the lower fresh- 
water formation at Whitecliff Bay, in 
which. this gyrogonite occurs very abun- 
dantly; they. consist. of beds of compact 
limestone, alternating with whitish calea- 
reous marls, and, in most of; them, the 
casts or shells of various fresh-water uni, 
valves 
