New York Agricultural Experiment Station. 127 



Well seasoned white pine was employed for an inner lining of the 

 refrigerator. This was given three coats of paint on each side 

 and both tongue and groove were freshly painted just before laying. 



Posts made of seven-eighths-inch whitewood glued up to prevent 

 warping were used for door-jambs and for the framework of the 

 doors. Paint was used to waterproof these posts on all surfaces 

 except those edges where the doors and jambs were to come in 

 contact. As neither paint nor varnish could be used there, and as 

 oil alone would cause the wood to swell, these edges were treated 

 with paraffin. The paraffin was driven into the wood by means of 

 a hot iron. The result of this treatment, in protecting from moisture 

 and' in preventing the door and jamb from sticking together, has 

 been entirely satisfactory. 



Half-inch seasoned cherry was used for the incubator shelves and 

 their supports, and seven-eighths-inch seasoned oak for the ice-rack 

 and ice-fenders in the refrigerator. Since these were to be exposed 

 to considerable moisture, they were thoroughly impregnated by 

 stewing the finished pieces for at least thirty minutes in melted 

 paraffin. The oak ice-rack, after this treatment, although it stands 

 constantly in water, has not warped in the slightest; but in the 

 shelves of the 18° incubator, which contains a saturated atmos- 

 phere, some warping has occurred. 



Throughout the construction, every piece of lumber was treated 

 over its entire surface with paint or other substance designed to 

 prevent the entrance of moisture. 



Insulating material. — Cork-board x was the main provision for 

 insulation. This is a very efficient insulating material, and since it 

 can be cut accurately by either saw or bit, lends itself readily to 

 close construction. The sheets of cork-board used were four inches 

 thick, and one foot wide and three feet long. A single layer of 

 this thickness has proved satisfactory; but two layers of three-inch 

 stuff, laid with broken joints, would undoubtedly have furnished 

 better insulation, thus reducing both the consumption of current 

 and the heat transference from chamber to chamber. The joints 

 between the sheets of cork were cemented with Nonpareil Water- 

 proof Cement. 2 This cement has served its purpose perfectly; but 

 it is so expensive that some other binding substance might prove 

 cheaper and more satisfactory. 



Metal. — Heavy zinc was used in lining the refrigerator to protect 

 the walls from moisture and from mechanical injury. 



Shelves, shelf supports, and drip-pan, in the refrigerator, were 

 made of galvanized iron. 



Brass pipe was used for the drain to the refrigerator and the 

 cooler of the 18° chamber. Its external diameter is at most places 

 one inch, but a short length is of inch-and-a-quarter pipe. The use 



1 Nonpareil Corkboard, obtained of Armstrong Cork Co., Pittsburg, Pa. 



2 Obtained of Armstrong Cork Co. 



