The daily union. [volume] (Washington [D.C.]) 1845-1857, 1847-10-19
MISCELLANEOUS.
From Chambers's journal
Artificial Cold.

ARTIFICIAL Cold.
Since the days of that disspaied heather who in or
der 10 cool the air during oppressive summer, caused
mountains of be piled up, and suffered them
melt away down to the present era in which there pre-
walls rage for the thing, mankind has been necessarily
in quest OF refrgeraves In those regions where ice
and found during winter, became an easy ex
pedlent to store up such treasures oil cold Tor use IN
warmer seasons but where if formed at ALL they could
only be OF momentary existence, II is manifest thai
some other means must be devised to supply the luxury
OF GOODNESS to the noble and wealthy and thus the arr
OF ARTIFICIAL rerlgeraton-an art which has to boast OF
the elaborate researches OF the ingenious Robert Boyle,
and has occupied much OF the consideration OF other PHI
iosophers before and snce-took its origin We have
already taken notice Of the prevalent use and means
Of procuring beautiful ice for the table we shall here
present bref sketch OF the history, and short notice
OF the methods, Of producing cold artifcally
Cold as luxury, was far from being unknown to the
anclents The winters ice was rudely gathered
up m heaps, or buried in pits, and covered with straw
chaff But this was wastefu, and grew to be an
pensve method and it became desirable TO have ready
means at every season, and independently of the acct
dents OF the skies, for obtaining the same end The
simplest OF these proceeded the principle OF loss OF
temperature, as result OF rapid evaporation The Egyp
tans were accustomed to cool their by placing
in earthen pitchers, the exterior of which kept
santy wet by being sprnkled with water by slaves. 1t
was the habit OF one OF their luxurious monarchs to
have several servants for this Office alone whose duties
were to expose the water TO cool the summit OF the
palace and constantly supply the royal table with the
beverage Cooling pits were also dug in the earth, into
which the vessels were placed during the daytime
the exterior being we'll soaked with water and then
rounded with the fresh eaves%o vine or other plant
evaporation rapidly went on and the liquid became most
agreeaby COOL Another method said to be mentioned
by Plutarch, which was, by casting into the water
number OF small stones, the agitation and consequent
evaporation produced by which would probably exercise
slightly frgorifc power over the water 1t probably
accidental observation of what could have failed
have been an everyday occurrence that led to the next
Improvement in this method of refrigeration Many of
the earthen vessels of the Egyptians are made of un-
glazed water placed one of these was found to
be considerably cooler than when kept in other vessels
and the more open and porous the material the rapid
tansudaton of the WATER and its evaporation from
the surface Of the jars, and the greater the degree OF cold
obtained Water-vases were then formed for that pur
pose solely; and the invention unaered in principle,
has come down with increasing usefulness to the present
time. Illustrations of the second great chemical law
that iquefaction produces cold-next followed For
in India it had been the practice to cool beverages
N that burning climate by dissoving sapere in water
From India the practice made its way into Europe and
Beckmann states that Spanish physician Barious Villa
Fmnca, practising at Rome, first introduced this method
OF producing cold in Italy about the middle Of the six
eenth century It is related that wine, placed in this
mixture, cooled to degree making it almost into
cradle to the teeth and this was considerable stem in
the history of artificial cold Other saline substances
came into use, and pits were formed into which, the
surrounded by the cooling mixture. Finally the
important discovery that an intensely freezing mixture
was capable OF being formed by mixing ice and
audience by exhibiting its effects upon bottle of wine,
which he actually froze into ice and this method
OF freezing water. is also mentioned by Lord Bacon
handed down to existing posterity.
little consideration Of the processes described in this
show they are al to the no
axons-that the evaporation and liquefacton create
cold the philosophy OF which fact is, simply, that in the
change of condition from fluid to vapor and from
solid to uid there is change in the capacity for cao
ric Ii certain Of water is to become vapor-
lzed or If certain weight OF salt is to become solu
the salt receiving additional supply of heat which
OF course absraced from all surrounding bodies and the
abstraction OF heat being an equivalent expression to the
production OF cold, brought back to the truths
with which we commenced, and have seen how evapo-
ration and lquefacon produce cold Calorc disappears
in both cases. and buyng itself among the particles Of
the new product is said to have become latent There
are some facts connected with the production OF artificial
ice which deserve mention here The congeation of wa
ter is materially promoted by rapid motion Water has.
IN fac been cooled, and yet remained quite fluid, many
degrees below the temperature at which generally be-
comes ice; but the moment little movement
municated to the liquid instantly the temperature TO
81 degrees, and the mass became ice needle crystals
flying through Its substance in most curious manner
This fact was seized upon by the refrgeratiss, and
peated accounts of making artificial are exant, in
which much stress is evidently laid upon the of STIR
ring the fluid to be frozen rapidly round with stick
experience OF mankind also appears to have discover
ly than otherwise. II is custom among many nations
OF warm climates either to the water in the sun,
to boil IT. previous to attempting to reduce its temperature
undertaken to determine the question and bis results
were that boiled water does freeze little more rapidly
than unboed The act of boiling expels the air. and,
as In freezing similar expulsion takes place, step is
gained IN advance of the unboied liquid
The means in present use for artificial refrigeration
very vaIlous--some OF them very interesting. Among
these the employment of porous earhenware may re-
ceve an early place. The Moors introduced into Spain
THIS article OF luxury in the shape of very elegant vases
wonderfully light and porous Water kept in these be-
came rapidly delicously COOL and from peculiarly
IN the process Of the manufacture Of the vessels, il
CURED, IN addition, very agreeable flavor. In Egypt,
and IN India, and in most suly regions, this expedent
n
Tor some time, been extensively employed amongst
selveporous wine, BUTTER and water coolers of many
elegant designs, being produced at poteries.
But porous keeps water coolest where the cline is
hottest the very increment of heat being made react
IN the production Of cold by rapid evaporation The
Moorish name Tor their earthen jugs was acarrdSos,
or bucdrros The Arabs burnt up with the eternal
fire of their scorching country, make use of goat
SKINS for their water vessels, which suffer little
water slowly to exude, and thus keep the remain
der comparatively cool A common method of cool
ing wines in India is one which will almost ap
pear paradox; the bottle is wrapped in flannel
weed with water and placed directly in the rays of the
sun: violent evaporation ensues, and the wine actually
becomes very cold 1t is plan, too, for sailors
in warm latudes to their wine with cloths con-
stantly wetted Apartments cooled on similar prn
clple and an abundance of water is frequently dashed
against the walls of the with the most grateful ef
feet. In India, Also the cold, dangerous and pene
ating clear night is applied in peculiar manner
for the purpose OF freezing water Near Calcutta in an
the ground, and filled with straw upon this many rows
of small shallow, porous pans, filled with water are
placed at sunset During the night ice forms IN thin
cakes upon the surface of these pans is carefully re-
moved before SUNRISE carried to proper repository and
pounded into mass there and then covered with