The Saint Paul globe. (St. Paul, Minn.) 1896-1905, 1899-06-25

it as he may happen to require for the
family refrigerator and for the cooling OF
| rooms through the medium of pipe-coils.
Beyond question, the next few years will
witness the passing of the iceman and
his fugitive daily lump, and before long
people will wonder how they ever could
have got along with such an incenvenient
and primitive method of supplying them
selves with cold. Already large business
concerns have almost wholly abandoned
the use of ice for refrigeration. substitu-
ting for it ammonia gas in pipes other
chemical devices for cooling, and there
is no reason why similar processes should
not be applied In the household. How
ever, the obviously economical way to
accomplish this is to furnish the cold
from central stations by pipe lines. wheth-
er through the medium Of brine
monia gas. or what not The ammonia
freeze Is even now being delivered in this
way. though on no very extensive scale
as yet, in three or four of our cities.
Early In the twentieth century the
householder Of moderate means will think
1t as much matter of course to turn on
the cold in his house in summer as to
turns on the heat in winter, and by the
help of means which as yet. are in the
experimental stage city dwellings, gener-
ally will be kept comfortable in the hot
test weather. Just the furnace or
steam heat Is concerned during the cold
weather. so the refrigerating apparatus
will be regulated In the dog days and
any undue elevation shown nv the yr,ar
curry in the thermometer will be rectifed
by the mere turning of key between
thumb and finger. Meanwhile the do
mestio ice box" erstwhile SO termed.
will do duty without a scrap of actual
ice. being supplied by the same agency
with n ACKNOWLEDGEMENTS chill.
BY actual trial. 1t has been proved prac-
ticable to keep various compartments of
a large refrigerator at different tempera--
lures by such artificial means. according
to the kinds Of foods that are to be pre-
served. and thus the system described is
specially applicable to markets, where In
one big box, fish may be held at 80 de-
grees. meat at 81 degrees. butter and milk
at AZ degrees. and fruit at A degrees
each perishable product, In short. at the
point required for 1t. Just as gas and
electricity are cheapened greatly now
adays by being supplied from central
stations. SO artificial cold can be furnish
ed In the same way for much less than
the citizen now pays for an equivalent In
the shape of Ice Consequently, 1t can
not be long before the new method re-
places the old. though probably ice will
always be used for cooling drinks and
for other purposes where the fancies of
appetite are involved
Among the most interesting of recent
IDEAS for refrigeration Is the power Ice.
cream freezer. This is an affair very dt:
terent in principle from the familiar do
mesuc apparatus, which, by the way,
was originated by Philadelphia woman.
Inc latter continuance stands today as
the most remarkable mechanical tnyen-
ton ever made by a person of the eentler
sex; 1t has never been improved upon
ana probably never will be- But the
power machine, used by concerns that
make Ice cream on large scale Is run
by steam, the cooling mixture of Ice and
salt being contained In q hollow drum
cynnder, which revolves In a tank filed
With raw materials of the product AS
the drum goes round, the ice cream stuff
Is deposited like frost upon the surface of
the cylinder. from which 1t is continI-
ously scraped by fixed knife and car
Red automatically to a suitable recepta-
Gle.
Quite number of freezing mixtures
for producing artificial cold are in use.
the cheapest and most common being
simply ice and salt. but the principle of
them all Is the same. When a. solid Is
converted into liquid, a certain amount
of heat disappears. Why this is So or
where the heat goes to nobody knows.
but it vanishes, and the result is cold.
This Is what happens when Ice is con-
verted into water rapidly by contact with
salt. lot of cold being quickly developed
and hence the freezing of Ice cream. But
1t is the same way with any other solid
substance, and there are some which in
liquefying yield more cold than ice will,