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filled with chaff or shavings, and fitted tightly to the door frame?, by 

 listing or cloth nailed over thin layers of cotton. (X.) The ice 

 chamber. (L.) Joists to support the ice floor, resting two inches on 

 the posts at Q. (N.) Iron bars, 1;^ inches wide, and ^ inch thick, 

 gained J inch into the joists, and placed crosswise to them. A bar 

 must always be put directly under the seams and rivets. Three bars 



are enough to be under a sheet 30 inches wide. (M.) The galvan- 

 ized iron ice floor, No. 18 or 20; the edges joined with rivets not more 

 than 1 inch apart, and very carefully soldered. The ice floor is put on 

 the edges of the iron bars so as to expose every part of its surface, on 

 ■which ice directly rests, to the air of the room below. (S.) Sides of 



