386 WHEN IRON LOSES ITS MAGNiETiG POWER. 
additional particulars are from the American 
Journal of Science and Arts. — Ed. M.M.] 
The following are some of the objects that 
have been subjected to the petrifying pro- 
cess. One of Sig. Segato’s first experiments 
was performed upon a Canary bird. It is 
Still preserved unaltered, although it is now 
ten years since the experiment was per- 
formed ; and it has been submitted to the 
action of water and of insects. A parrot re- 
tains its original brilliancy of plumage, 
unimpaired. Eggs of the land turtle, turtles, 
various tarantulae, a water-snake, a toad, 
various kinds of fish, snails and insects, are 
in a perfect state of preservation. To these 
are added various parts of the human body. 
A hand of a lady, who died of consumption, 
preserves the emaciation of the disease and 
of death. Another of a man is flexible in the 
different phalangic articulations, and yet 
unalterable; afoot with the nails perfectly 
fast; a collection of all the intestines of a 
child, in their natural colours and forms, 
with the fecal matters unremoved ; the liver 
of a man who died from intemperance, dark 
and lustrous like ebony ; an entire human 
brain with its convolutions, of extreme 
hardness ; the skin of a woman’s breast 
naturally configured ; a pate of a girl pefect- 
ly flexible, from which the hair hangs in 
curls ; the head of an infant partly destroy- 
ed, and discoloured by putrefaction. There 
is also in the cabinet of Sig. Segato a table 
constructed as follows. A spheroidal sur- 
face of wood contains a parallelogram, com- 
posed of two hundred and fourteen pieces, 
regularly arranged. These to the eye ap- 
pear like the most beautiful pietre dure that 
have been produced by nature. Their vari- 
ous colours, polish, and splendour, and their 
surprising hardness, would leave no doubt of 
their stony character. The sharpest file, 
with difficulty, makes an impression on any 
of them ; some it does not attack at all. 
These pieces are all portions of the human 
body, hardened by this new process ; as the 
heart, liver, pancreas, spleen, tongue, brain, 
arteries, &c. &c., all resembling the most 
highly-polished precious marbles. An entire 
body has not yet been tried, principally on 
account of the limited resources of Sig. 
Segato, although the expense would be but 
about one tenth of that of embalming by the 
ordinary process. 
Great advantages to science, especially to 
aatural history and human anatomy, are 
expected to result from this discovery ; and 
it is even confidently believed that the re- 
mains of friends, of men of science and of 
worth, may be preserved for ages in the exact 
form and appearance, in which the hand of 
death found them, wuth nothing offensive or 
revolting about them. 
As vouchers for the accuracy of the state- 
ments contained in the pamphlet, the cer- 
tificates of many of the distinguished phy- 
sicians, professors, and men of science in 
Florence, where Sig. Segato resides, are 
appended. Among them, it is sufficient to 
mention the names of Sig. Betti, Pro- 
fessor of Physiology; Sig. Zannetti,: Pro- 
fessor of Human Anatomy ; and Dr. Gaz- 
2 eri, Professor of Chemistry. 
MAGNETIC CHARACTERS OF THE 
METALS. 
The opinion of Dr. Faraday, as stated 
at the Royal Institution in reference to the 
metals, is, that they are all magnetic, just 
as they are all capable of being solidified, 
but that a proper temperature is the desi- 
deratum, as with mercury, for the solidifica- 
tion of which alow temperature is required. 
The analogy is principally derived from the 
case of iron which loses its magnetic power 
at an orange heat, and when cooled down 
regains its attractive power. Nickel exhibits 
similar properties. When heated and cooled, 
it retains its negative state long after it has 
ceased to be visible in the dark. Even 
when immersed in hot almond oil it loses its 
magnetic power. This point appears to be 
between fi.'iO® and 640«. Cobalt and chromium 
are stated in chemical works to be magnetic. 
Dr. Faraday found that specimens of 
these metals, which were said to be magnetic, 
derived that property from the presence of 
iron or nickel. The result of his experience 
in res})ect to chromium is similar to that of 
Dr. Thomson, who long ago determined 
that it was not magnetic. Dr. Faraday 
endeavoured to excite the magnetic power 
in a number of metals by sinking their 
temperatures to 60“ and 70«, but could not 
succeed; nevertheless, he is convinced that 
the only desideratum, in reference to the 
development of magnetism in all metals, ii 
the particular magnetic temperature. 
NOTICE OF SOME RECENT IiM- 
PKUVEMENiS IN SCIENCE. 
CIlEMISTUY. 
I. SOLpIFICA ITON OF CARBONIC 
ACID. — Tliiloiiet lias succeeiled in reducing 
tliis gas to a .solid state, by exposing it to a 
tempeiatuie of l48*^ F. (?) Even when 
exposed to ilie air, it remains in tliis.-tate for a 
slion lime. Its elastic force appears tp bo 
deteiiorated by being solidifieil, as in this 
state it trradnally dissipates. It m.ayt4re also 
rendered solid by suddenly raising it fiom a 
liquid 10 a gaseon.s stste. VVlien a stream of ' 
the acid is direcled inio a small glass pliial, 
the latter is filled wiili a white powder. If a , 
small poition o( the solid acid is placed in a i 
stopiiered vessel, it soon fi L the flask vviih a i 
thick vapour, and ilie stopper is foiciuly 
expelled.— Medicate, Oct., 1835. 
II. NAPHTHALINE AND IIS COM. ' 
POUN US.'~ Na-phthaline was procured by I 
Laurent, by boiling coal-tar in the open air | 
until it was depiived of its water, arid’ then : 
distilling it in a retort with a copper beak and |i 
