554 
cipal points to which the supporting threads 
-were attached formed here, as they usually 
do, an equilateral triangle. One thread 
was attached above to each of the trees, and 
the web hung from. the middle of it. To 
procure a third point of attachment the spi- 
der had suspended a small stone to. one end 
of a thread; and the stone being heavier 
than the spider itself, served in place.of the 
lower fixed point, and held the web extended. 
‘The little pebble was five feet from the 
earth. The whole was observed and is 
described by Professor Weber, of Leipzig, in 
a German journal. A case exactly similar 
was witnessed by the writer hereof, and 
described in the MontHLY MaGaziIneE, 
about two years since. 
Melting Point of Silver, and its Alloys 
with Gold.—Mzr. Prinseps of Benares, in a 
very able paper on the measurement of high 
temperatures, has given the following ave- 
rage results, which are of great importance. 
Full red heat, 1200° Fahrenheit; orange 
heat, 1650; silver melting, 1830 ;. silver, 
with one-tenth gold, 1820 ; silver, with 
one-tenth gold, 2050. Mr. Wedgewood 
made the melting point of silver so high as 
4717°, and Mr. Daniell 2233°. 
Polar Red Snow.—According to the che- 
mical examination of the red snow brought 
from the north by Captain Franklin, 
M.M. Macaire, Prinsep, and Marcet are 
inclined to think it may be of animal pro- 
duction, and not vegetable, 7. ¢. consisting 
of animals and animaleules. The ana- 
logy of this substance to a red matter taken 
from the lake of Morat, was one among 
other reasons for this opinion ; and also the 
circumstance that gelatine, containing azote, 
‘has. not as yet been found in the vegetable 
creation, whereas it is in this red snow. 
Mineralogy.—A. curious specimen of 
common blue chalcedony, having in it a 
cavity half full of a limpid fluid, not unlike 
water, is now in England. The specimen 
has been ground and polished all round the 
cavity, so as to leave a crust of chalcedony 
about one-tenth of an inch thick. The ex- 
ternal dimensions of the. specimen are, two 
inches long by one inch. broad, so that the 
length of the cavity. is at: least 1*7 inches. 
The price asked for this specimen is. thirty, 
guineas.’ If the fluid is water, it is not 
worth the tenth part of that sum ; but if it 
is, which is not probable, one of the new 
fluids discovered in topaz, the specimen 
_ would be invaluable, 
Congress of Philosophers at Berlin.—At 
the great congress of philosophers which was 
held at Berlin on the. 18th of September of 
last year, the numbers sent by different king- 
doms were, Russia, 1; Austria, 0; Eng- 
land 1; Holland, 2; Denmark, 7 ; France, 
1; Sardinia, 0; Prussia, 95 ; Bavaria, 12 ; 
Hanover, 5; Saxony, 21 ; Wirtemberg, 25; 
Sweden, 13; Naples, 1; Poland, 3; Ger- 
man States, 43. Total, 206. Berlin, 172. 
“¢ Total of the whole,”’ 378. 
. New Field Sport,—A. sportsman at Nee- 
Varieties. 
‘May, 
mutch, in’ Bengal, during thé last hot ‘sea- 
son, made a practice of sitting up alone at 
nights, near pieces of water, in the midst of 
the jungles, with only a double-barrelled 
Manton, in quest of tigers and other wild 
beasts. A small embankment of loose 
earth, raised about a foot and a half, was the 
only cover he had, and this was, of course, 
more to keep him out of sight’ than to afford 
protection. In this manner he has killed 
tigers, leopards, elks, hyenas, and hogs, 
without having occasion to deliver a second 
shot, allowing them to approach within ten 
or twelve yards of him, which was easily 
effected in the obscurity of the night. Ona 
few occasions he was in great danger, one 
night particularly, when the animal he 
fired at sprang into the middle of the nullah 
near to which he was sitting. This surely 
is a more dreadful trade than that pursued 
by him who gathers samphire. 
Morbid Structure. —A very singular and 
curious case of cutaneous enlargement has 
been met with in India, in a lad about six. 
teen or eighteen years of age. The skin of 
the left thigh to below the knee has become 
a loose pendulous mass, covered with strong, 
black, crispy hair, like that of the beard or 
whiskers. . There has been some peculiarity: 
of the limb ever since his birth ; but he feels 
no inconvenience in walking, excepting 
from the increased weight. The temperature 
of the enlargement is about three degrees of 
Fahrenheit warmer than the other parts of 
the body. The lad appears to be otherwise 
healthy. a 
Magnetism.—From ; a series, of experi- 
ments with various instruments, the dip of 
the magnetic needle in London, in August 
1828, was ascertained to be 69° 47’ N., 
which compared with observations made in 
August 1821, gives a decrease of 17’*5 in 
seven years, or an annual decrease of 2/5. 
The average annual decrease e century. 
preceding 1821, appears from the. most — 
authentic observations, to have exceeded 3/4 — 
Pendulum Experiments.—Professor Bes- 
sel has lately published the first part of his 
pendulum experiments, which contains the 
investigation of the length of the pendulunt 
at. Koenigsberg. The final results he has 
obtained: are the following: length of the 
second, pendulum in the observatory of 
Koenigsberg—=440-8147 lines, Parismeasure, 
by the toise of Peru. The same reduced to 
the level of the Baltic=440-8179. 
. New. Safety Lamp.—The safety lamp 
of Sir H. Davy is known to be in many 
respects very defective, and frequently pro- 
duces the danger it is intended to avoid, by 
a misplaced confidence in its capability and 
protection. Its illuminating power is but 
»small, and when in an impure atmosphere 
that power is so far diminished as to render 
it of little or no service. This will ever be 
an inducement. to the miner to remove the 
top, even at the risk of life. A lamp, free 
from al] these imperfections, has recently 
been invented; it consists of a vessel in 
