The Madisonian. [volume] (Washington City [i.e. Washington, D.C.]) 1837-1845, 1838-11-24
From the Philadelphia Ledger.
THE WONDERS OF SCIENCE.

This had already been done about TWO years since,
by M. Thilorier, of Paris, in some experiments
whose results were reported 10 the Royal Academy.
Professor Mitchell was obliged TO devise and invent
his apparatus, M. Thillorier described only his
experiments and gave account OF his instruments.
As some of our readers may be imperfectly ac-
quinted with the technical terms OF chemistry, we
shall endeayor 10 explain such as we are obliged TO
use. Carboatc acid Is the gas liberated in The vinus
fermentation Of beer, cider, wine, and other aico-
holic liquors; In most artificial mineral waters, and
in the Saratoga and all other eervescing or spark
ling mineral springs and 10 bread in the process Of
rising. II is an acid, uniting with alkalis earlhs
and metals, forms variety OF salt. With soda, II
forms one Of the two ingredients OF soda powders;
with ammonia, or animal alkali Il forms the white,
pungent salts used for smelling bottles; with lime, il
forms chalk with lime and water, Il forms marble;
with potash, it forms pearlash. IL Is composed OF
about % paris Of carbon or pure charcoal, and ~
parts Of orugen gas, vital air. It's specific gravity
or weight compared with that oil water, Is about
0000lS. In other words IL cubic foot Of water
weigh GO pounds cubic foot Of this gas weighs
about GIL grains, or Ii ounces II Is heavier than
atmospheric air, and is therefore always found on
the floors cellars apartments where liquors
in the process Of fermentation and sometimes the
bottoms of wells or caves or the latter, the cele-
braIed Grotio del Cane, in Italy, Is an instance.
To render this gas risibh and tangible Is the OBJ
ject of Professor Milchells experiments; and this
Is accomplished by snbecting IT, at the temperature
Of Sc deg Fahrenheit, 10 the enormous pressure of
about 1000 pounds to the square inch or nearly 20
for this purpose Is the following A cylinder Of cast
iron, six inches in diameter is bored like cannon,
TO the cabre Of three inches, which leaves its walls
one inch and half in thickness. The orice at top
Is closed by the screw Of wrought iron, projecting
beyond its edge in shoulder, WHICH ~ lined with
lead to render the cylinder perfectly tight and thus
to prevent the escape Of the gas. This cylinder,
about two feet long, communicates with another OF
the same diameter and thickness and about six inches
long, by means Of tube, furnished with stop cock;
the ends OF the tube being conica and inserted into
brass cones, screwed into the iron cylinders The
cone is used as the only form found capable on trial.
of conveniently resisting the enormous pressure of
the gas From the small cylinder projects another
tube, furnished with stop cock, to which may be
screwed phial or other vessel, for receiving the
liquid or frozen gas
About Ii pounds of mpercarbonate of soda, one
Of the ingredients of the common soda powders,
put into the large cylinder; a tin cup, about IL
inches long, and containing about or 10 ounces OF
sulphurc acid is placed in the cylinder the Of
this cup being TO prevent any mixture of the acid
with the salt before the cylinder is closed. The
screw being fastened to the orice, and the cylinder,
which is suspended between two perpendicular posts
by trunnions being inverted, the contents mixed;
the soda, having greater affinity for the suphuric
than the carbonic acid, unites with the former and
forms suipaate Of soda, or Glaubers salts, and the
latter is liberated in great quantities in the chamber
OF the cylinder. Being very elastic, and confined
within this narrow space, the carbonic acid IS sub
Ject TO the enormous pressure OF about lO0O pounds
To- the square inch, and is condensed into liquid,
coloresS and transparent like distilled water As
ealore sensible heat is liberated in great quantities.
on the mixture of soda and sulphuric acid for the
outside of the large cylinder inches thick, is con-
sderably heated the carbonic acid passes into the
short cylinder in the liquid state, at low tempera-
ture. phial being screwed to the stop cock OF the
short cylinder, and immersed in mixture Of snow
and SALT which produces the degree of cold indicated
by the zero Of Fahrenheit or 80 degrees below the
freezing Of water the gas is received into it in the
ct In yNhs to ptrta IN
with the air, part of the liquid is suddenly evapo
rated and the rest frozen The phial being removed
and replaced by close tin vessel, all the gas re-
manning in the large cylinder is admitted into it, and
part Of il is found frozen into snow. This snow
is light dry and very cold TO the touch beautifully
white, and when first exposed to the atmosphere at
the temperature Of minus 80 deg, is l22 degrees be-
low the cold OF frozen water. As rapid evaporation
Immediately ensues visible in the appearance of
white vapor, and carrying off calorc, this low tenn
perature rapidly falls TO 100 or lao degrees below
zero.
Mercury, which freezes at 40 degrees below zero,
becomes solid in a few seconds, when, enveePed IN
this snow. Ii ether be added to this snow, The pro-
cess of freezing is greatly facilitated; The evapora
ton, and consequent absorriion o. caiofic, oeing
abonf che hardness OF lead, and exhibits the same
appearance when cut with knife.
This snow, when laid upon red hot iron, is not
rapidly melted and expelled with ebullition, like
water or common snow, but remains quiescent till
entirely evaporaed. A quantity the size of pea,
laid in an iron lade heated to bright redness disap
peared in about thirty seconds, but remained without
agitation in the mean time. Snow or ice is first
melted, then raised to boiling heat, then evaporated;
but o. this frozen gas the only change is from
to vapo and the latter at such very low temperature
SO rapidly absorbs calorc from the heated iron as
to prevent any from passing into the remaining snow
Hence, during the whole process of evaporation of
this frozen gas upon red hot ron the temperature of
what remains in the state of snow is not raised.
1t was thought that carbonic acid, thus condensed,
ing power. But II never can be used as substitute
for steam; for besides the expense of producing it,
its expansion is only GOO times The bulk Of the liquid,
while that OF steam is nearly 100 times the bulk Of
the water from which il is formed.
Professor Mitchell is now engaged with course
of experiments upon this gas, thus solidifed, which
will be made the subject of a communication to the
franklin Institute