150 REFRIGERATION AND REFRIGERATOR INSULATION ON BOARD SHIP. 
for refrigerators, but for the above-mentioned reason are not desirable as ordi- 
narily installed. 
The method that was used for correcting this set of refrigerators consisted 
in removing all of the defective insulation, replacing it with pure cork sheets set 
in Portland cement, using two layers of 2-inch sheets as before, and then finishing 
the inside of the refrigerators with cement with rounded or cove corners. In this 
way all air spaces are absolutely eliminated and a practically permanent structure 
is secured. 
There is, of course, a tendency which cannot be avoided for the cement to crack 
as it dries. This is taken care of by scoring the surface in rectangles so that the 
cracking occurs on these lines, and after the cement has thoroughly dried these 
cracks are filled with a paint, 7. e., a white enamel paint that is used for a final 
finish on the surface. 
A refrigerator finished in this way is not as attractive in appearance as the 
glass, or, for that matter, even the porcelain enamel on metal, but it is certainly a 
more sanitary structure. 
Another way to overcome the cracking difficulty in the cement is to give the 
cork a skim coat of cement, then bed into this either a sheet of expanded metal or 
wire mesh of some kind, and then apply a final coat of cement. The two layers of 
cement are used to avoid any possibility of air spaces being left if the metal is se- 
cured direct to the cork, and then only a final coat of cement applied. 
A further difficulty in the original design of the refrigerators under discussion 
was brought very forcibly to the attention of the men who did the actual repair 
work on this job. The work, unfortunately, had to be done while the kitchens were 
in service, and, although the weather was not especially warm, the men found the 
interior of the refrigerators so hot that it was impossible to work any length of 
time without going outside to cool off. Ranges and steam kettles were so close to 
the refrigerators that there was only space sufficient for the men working on the 
ranges and kettles to get about them and for a rather narrow passage behind them, 
i. e., between them and the refrigerators. When one stops for a moment to con- 
sider the purpose of insulation—namely, to prevent the flow of heat into the refrig- 
erator—it would seem reasonable to so arrange the building as to reduce as far as 
possible the temperature to which the outside of the refrigerator is subjected. 
In insulating refrigerators that are “built in” on board ship, the best construc- 
tion with which the writer is familiar is that illustrated in Plate 75. The 
insulating material—namely, pure sheet cork—is cemented with a special cement di- 
rectly to the steel surfaces forming the compartment. The second course of cork 
is set in asphalt after the first course has been carefully pointed up with an asphaltic 
cement mixed with fine re-granulated cork. In this way all possibility of air spaces 
is eliminated and the chance of any moisture accumulating is avoided. 
The inside surface may, in this case as in the insulation described before, be 
finished in cement, although in some classes of work the cement can be omitted and 
an asphalt finish used instead. 
