316 
ments. A piece of wire-gauze being laid 
upon the glass chimney of a common 
argand gas burner, the flame is immediately 
enlarged to twice its former dimensions, and 
its light fully doubled. (A similar experi- 
ment being tried with a common argand oil 
lamp or reading lamp with a flat wick, the 
flame is often enlarged, but so discoloured 
as to yield less light). Place the finger or 
a bit of cork, so as to close the lower open- 
ing of the interior air passage of a common 
argand gas burner: the flame experiences 
a sudden enlargement with an increase of 
light nearly equal to that in Exp. 1. (the 
inner air passage of an argand oil lamp 
being closed, the flame is greatly deterio- 
rated and darkened.) The air tube of an 
argand gas burner being stopped as in Ex. 2. 
and the fiame consequently. enlarged no 
further change happens when wire gauze is 
laid on the top of the glass chimney. Over 
the glass chimney of a single jet gas 
burner, wire gauze being laid, produced no 
enlargement of the flame and no increase of 
the light. . In an experiment at the rooms 
of the Mechanics’ Institute, York, it was 
found that one hundred feet of gas were 
consumed in three hours and twenty-five 
minutes by six argand gas burmers in the 
ordinary state, while the same gas burners 
provided with wire gauze caps to their chim- 
neys yielded an equal light for an equal 
time, but consumed only about fifty feet of 
gas.— Phil. Mag. 
The Apotheosis of Travellers. — The 
beams of light seen at times to issue from 
the sun through the interstices of dense 
clouds when that luminary is near the hori- 
zon, appear by the laws of perspective, 
to diverge from the sun, but are, in fact 
parallel; and when seen of considerable 
length, they of course appear arcs of great 
circles. When the sun is in, or a little 
below ‘the horizon, they are often seen 
to converge toa point diametrically opposite, 
and are seldom seen far from the vanishing 
point. These beams are produced in the 
same manner as those in a room where 
there is smoke or dust and the sum shining 
in through the window. The vanishing 
point of the solar beams is seen in the sea 
when transparent and smooth, and the sun 
shining at least 60° cr 70° above the hori- 
zon. ‘Then by looking over a vessel’s side 
opposite to the sun, the spectator will see 
around the shadow of his own head only a 
kind of corona: the same phenomenon may 
likewise be observed in a stratum of fog, 
when the sun and observer are in certain 
positions. This has been called the apothe- 
osis of travellers. The appearance is caused 
either by rain, fog, or spray, on the same 
principles as the common rainbow. A line 
drawn from the centre of the sun passing 
through thé eye of the spectator, who has 
his back to the sun, passes through the cen- 
tre of the bow; consequently if the spec- 
tator be elevated above the horizon, as when 
ona high mountain, he may see the entire 
Varieties. 
(Marcu, 
bow, encircling like a corona, the head of his 
shadow projected on the subjacent plain or 
upon the clouds. 
Crystal Bed.—_Immediately before the 
late war broke out between the Russians and 
the Persians, a bed of massive crystal-was 
made in the imperial manufactory of Pe- 
tersburg to be sent as a present to the Shah 
of Persia, by the Emperor of Russia. This 
magnificent bed, the only one of the kind 
perhaps in the world, is resplendent with 
silver, ornamented with columns of crystal, 
and ascended by steps of blue glass. It is 
constructed in such a manner that there can 
be made to issue from it on each side jets of 
odoriferous water, the murmuring sounds of 
which may excite an agreeable slumber. 
It reflects by the light of flambeaux a daz- 
zling splendour, resembling myriads of dia- 
monds. There is no doubt that this piece 
of furniture would nave astonished even 
eastern luxury and magnificence. 
Sieam Artillery.—In a memoir on the 
comparison of the mechanical effects of 
gunpowder and steam, as applied to artillery, 
a German author, Herr Prechtl, concludes, 
from a series of analytical deductions from 
facts and experiments, that steam artillery 
will never offer practical advantages over 
powder orduance, and that it is an inven- 
tion to be ranked among the number of dis- 
coveries more curious than useful or appli- 
cable. 
Earthquake in India.—A smart shock 
of an earthquake was felt at Bhooj, in 
Cutch, on Sunday, July 20, 1828, about 
1 p. m., and although it does not appear 
that any accident has happened there or in 
the surrounding neighbourhood, the vibra- 
tion was so great as nearly to spill water 
from a tumbler half full. The day was dull 
and somewhat close, and in the evening 
there was a heavy shower of rain. The 
shock, as far as could be judged, was from 
East to West. 
Natural History.—An account has been 
communicated to the Lyceum of Natural 
History of New York, of a case of singu- 
lar malconformation observed in the teeth 
of the Arctomys Monax. In this individual 
there had been a cavity in the lower jaw, 
which had prevented the growth of the 
incisor on that side. Its antagonist in the 
upper jaw having nothing to oppose it, had 
continued to be developed until it had de- 
scribed more than one complete spiral revo- 
lution. There is in England, in the posses- 
sien of an eminent scientific surgeon dentist, 
Mr. Snell, the head of a rabbit, in which 
the grinding surfaces of the inside teeth of 
the upper and lower jaw, not being in con- 
tact, the teeth had described more than 
half a spiral revolution. 
Drinking Ice Water.—It has long been 
known that ice water debilitates the stomach 
much more than spring water of nearly the 
same temperature. On two very hot days 
in the month of June 1828, some experi- 
ments were made in America, with ice 
