Cork insulation; a complete illustrated textbook on cork insulation ...

342 CORK INSULATION
Nevertheless, the more progressive refrigerator manufac-
turers and the more progressive producers and distributors of
ice, often in cooperation with various United States Govern-
mental agencies, State Universities^ and a few private experi-
mental laboratories, kept up a constant if not intensive search
for more practical and accurate information on the application
of refrigeration principles and appliances in the home
New and better sanitary refrigerator linings were developed,
air circulation was ^•astly improved, shelves were rearranged
to accommodate various foods in the position in the refrig-
erator where they would keep best, better hardware was
adopted, doors were sealed with improved wick gasket, drain !
pipes were placed so as to permit of ready removal and clean-
ing, ice compartments were enlarged to an adequate size,
outside icing doors were provided for the discriminating, and
better exterior finishes were offered. Very little attention,
however, was paid to the <strong>insulation</strong> of what would other-
wise have been a perfect masterpiece of craftsmanship. A few
manufacturers, among them those using solid porcelain lin-
ings, adopted granulated cork as the insulating medium; but
as refrigerators were not then sold on the basis of compara
tive permanent efficiency of operation in service, the added
value of the ground cork <strong>insulation</strong> was not generally appre-
ciated even by those manufacturers who used it.
154.—The Advent of the Household Refrigerating Machine
and Early Trials with Pure <strong>Cork</strong>board in Household Refrig-
erators.—It has been seen that the practice of cooling food and
dfink below the temperature of the atmosphere by the use
of snow and ice was followed for many centuries before natural
ice came to be stored in caves, in ice pits, and then in ice
houses, and that within the present generation means were
perfected for the manufacture of ice in commercial quantities
for refrigeration purposes. Now we observe that within
scarcely the past dozen years attention has been directed tO;
ways and means of producing refrigeration in the home by
mechanical means directly ; but it is only since the World War
that the household machine has been manufactured in quan-
tities and proven a success, the production during recent years
having been about as follows
: