REFRIGERATION AND REFRIGERATOR INSULATION ON BOARD 
SHIP. 
By Rosert F. Massa, Esq. 
[Read at the twenty-fourth general meeting of the Society of Naval Architects and Marine Engineers, held in 
New York, November 16 and 17, 1916.] 
INSULATION NOTES. 
In the following notes on refrigerator insulation it is the writer’s intention to 
call attention to several elementary physical facts—facts which everyone knows 
and the regard for which would seem to be engineering common-sense, and yet facts 
which are very apt to be neglected in insulating cold storage compartments. 
Some repair work recently done on refrigerators in a large New York hotel 
offers an excellent example of how not to insulate a cold room. The fact that this 
was a stationary installation does not affect its importance as an example of wrong 
method. 
These refrigerators, when they were originally built, were constructed by ce- 
menting cork sheets against concrete floor, walls and ceiling, with wooden strips 
set in the cork. The cork was applied in two layers, each 2 inches thick, the second 
layer being secured to the first by cement and the strips of wood being set in the last 
layer applied. To these wooden strips there was secured an inner lining for the re- 
frigerator made of white porcelain-enamelled sheets of steel. 
Upon examining this refrigerator after several years’ service, it was found 
that the insulation, particularly in the lower part of the box, was water-soaked, 
that the steel had been almost completely rusted out, that the wooden strips holding 
the metal in place had rotted away, and that the moisture had worked down through 
the floor and was getting into the wine room located directly below the refrigerator. 
The defect in this design lies in the fact that it is not possible to fit these enam- 
elled sheets close enough to the cork to do away with air pockets, and, if these 
pockets exist, the variations of temperature to which they are inevitably subjected 
mean alternation of pressure within them, and, consequently, interchange of air 
with the outside, the deposit of moisture and its gradual accumulation. 
This deposit of moisture is increased where the cooling surfaces are placed 
close to the walls of the refrigerator, this action being due to the greater deposit 
of moisture at the lower temperature, and, further, to the greater variations in tem- 
perature to which air pockets near the cooling surfaces are subjected. 
This same difficulty of making a perfectly tight wall holds, not only with the 
white porcelain-enamelled sheets, but with all metal sheets and with glass refriger- 
ator lining. These glass linings are one of the most attractive appearing linings 
