The Minneapolis journal., 1902-06-21
ARTIFICIAL ICE
It ExceIs the Natural Product in Point of Purity but Melts
Sooner How the Business Has Grown and How 1t IS
Conducted - {@=.e
Boston Transcript.

Boston Transcript.
Few American industries are so ex-
traordinary in their character or make a
more surprising exhibit of progress in the
last decade than the manufacture of Ice.
Here is commodity of which nearly two
thirds of the cost of production is in
coal, about one-tenth in ammonia and
practically none of it in anything which
actually enters into the product. Often
a natural spring is secured in connection
with an ice factory, but this must be
largely for advertising purposes, since in
making "can ice,' which is the usual
process, any water must necessarily be
distilled or the ice would be Opaque. And
distillaton leaves the "hygehic spring
no advantage over the hydrant. JACK
Frost can make crystals out of muddy
water, but not the art of man.
The manufactured ice business started
in New Orleans in 1866, and has been
steadily moving northward, till to-day the
country may be divided into three zones,
in the southern of which the manufac-
tured Ice holds the monopoly; in the
northern the same thing is true Of the
natural product, while there Is middle
zone where the two are in actual ana
more or less vigorous competition These
zones, the recently issued census office
bulletin exhibits in map, and by ac-
companying figures shows that the range
of competition is moving northWard Zen
years ago the distinctly southern states
had three -fourths of the manufactured ice
plants in operation in the country; to- day,
although there has been good numerical
increase in the SOUTH this has been, ,mucn q
| more than Offset in other parts OF the
country, SO that the southern total is now
| only 40 per cent of the establishments.
Differs From Natural ice.
I,,11 1nfir
not enter into an examination OF the rela-
tive merits of the two products; that they
differ in essential properties about as
much as cane and beet sugar, butter ana
oleomargarin, is the experience of most
housekeepers. That the manufacturer
ice is increasing in its staying qualities
is probable, in view Of the constant I'M
provements in the processes Its manu-
facturers already claim that it is fully
equal in this respect to the natural ice,
hut that they have secured the trade OF
fish packers and other critical buyers OF Ice
! in the competitive zone may be doubted
| On the other hand, manufactured Ice pos
sesses the obvious advantage of greater
| purity Without entering into discus
sion here of what germs may be kept
alive and conveyed in ice, none can deny
| that a distilled water product Is the
| purest thing possible. Thus the natural
| article excels in one thing and, the manu-
factured in another, and buyers IN the
| competitive area, are doubtless making
| their selection according to the property
| which they want the most.
| The surprising growth of this Industry
| resembles the accounts of manufacturing
progress Under a new protective tariH
| here was an American industry Wnlcn
| started an infant, and against the great
est of natural odds; by the progressive
display of our native ingenuity II mas
now reached the stage where. It, employs
| thousands of men and millions OF capital
| and what is vastly more important. has
| opened the way for the development, IN
the south and on the Pacific coast, OF
| many industries which were: Impossible
before the days of artificial refrigeration
The Means Employed.
In the manufacture of ice there are
two systems used, commonly known as
the compressor" and the absorption
systems The compressor system, by far
| the more common, involves three success
sive steps, respectively called, compres
sion, condensation and expansion! AN
hydrous> ammonia. or ammonia wnlch
contains no water, is subjected In the
gaseous form to a pressure of from LIE
l to ITS pounds per square inch, by the
use of a power pump. The gas contains
a certain amount of heat and substant1-
ally none Of this is lost by compression
The gas is next reduced to the tlqulc
state by condensation. This is performed
by passing the ammonia through coils o
pipe. in contact with cold water. The
excess of heat is thus given UP, and the
ammonia, reduced to the liquid state, Il
then made to become gaseous in coils o
pipe which are in contact with the waite
to be frozen. This reduces the temper
ature of the ammonia gas below tn
freezing point of water, and the am
.monia absorbs from the water to b.
cooled the heat which was taken from The
former during condensation. This results
>in freezing the water, owing&to the we'll
known fact that if two substances O
different temperature are allowed t.
come in contact with each other tn
ri warmer body will impart it's heat to tn
colder, until the temperature Of the two
are equalized| This is the theory of al
refrigerating processes. The ammonia
having completed it's cooling work, II
then returned to the compressor, where
may be reused repeatedly. There is
however, small loss during each cNcl
of operations, and the supply must be re
plenished at intervals.
In the United States.
Practically all of the ice manufacture,
, in the United States is produced by tn
, can system or by the plate system. Il
the can system ice may be formed .eithe
in stationary cells or in removable cans
the latter being the method In more gen
eraI use. The time required for tn
formation Of the ice varies from twent
to sixty-six hours, according to the thick
ness of the mold containing the waite
to be frozen and the temperature of tn
brine.
In the plate system hollow iron plat
J is immersed in a tank containing tn
water to be frozen, and as the plat