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Tile' "Novelties" Exlzibition. 399 its upper part, connects with a general air-space, situated under the roof of brick-work enclosing the furnace.
This space or reservoir of hot-air is tapped, as may be desired, with pipes, conducted to the several apartments to be heated.
THOS. H. HOLMES, PHILADELPHIA.
Newton's Β£Team-Trap.--An objectionable feature of this trap, in our opinion, is the hinged cock, or connection from steam-pipe, which is liable to be a source of trouble.
We recognize the efficiency of the trap at the expense of considerable steam, and the mechanism is liable to get out of order.
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