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Sunk into the floor were numberless tin boxes, a foot square and two feet long, and open at the top end. These were full of clear water; and around each box, salt and other proper stuff was packed; also, the ammonia gases were applied to the water in some way which will always remain a secret to me, because I was not able to understand the process. While the water in the boxes gradually froze, men gave it a stir or two with a stick occasionally--to liberate the air-bubbles, I think. Other men were continually lifting out boxes whose contents had become hard frozen. They gave the box a single dip into a vat of boiling water, to melt the block of ice free from its tin coffin, then they shot the block out upon a platform car, and it was ready for market. These big blocks were hard, solid, and crystal-clear. In certain of them, big bouquets of fresh and brilliant tropical flowers had been frozen-in; in others, beautiful silken-clad French dolls, and other pretty objects. These blocks were to be set on end in a platter, in the center of dinner-tables, to cool the tropical air; and also to be ornamental, for the flowers and things imprisoned in them could be seen as through plate glass. I was told that this factory could retail its ice, by wagon, throughout New Orleans, in the humblest dwelling-house quantities, at six or seven dollars a ton, and make a sufficient profit. This being the case, there is business for ice-factories in the North; for we get ice on no such terms there, if one take less than three hundred and fifty pounds at a delivery.