Ventilation : a text-book to the practice of the art of ventilating buildings with a supplementary chapter upon air testing / by William Paton Buchan.

  • Buchan, William Paton.
Date:
1891
Catalogue details

Licence: Public Domain Mark

Credit: Ventilation : a text-book to the practice of the art of ventilating buildings with a supplementary chapter upon air testing / by William Paton Buchan. Source: Wellcome Collection.

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    LAYING AND LEVELLING DRAINS. thick, 2J in. broad, and either 3 ft. long, as per l, or 3 ft. 9 in. long, as l + c in sketch. Suppose the drain-pipes are in yard lengths, exclusive of the faucet, and it is intended to give each pipe a fall of \ in. or 1 in 72, then a small piece of iron, brass, lead, or wood \ in. thick, is fixed on at H, (' 0*\ then at other end a piece of wood, or its equivalent, is fixed on at r, f in. thick. When the pipe q is put into the pipe p, and the spirit- level, s, is applied, as per A or b, it will easily be under- stood that when the air bulb stands at a or b, the faucet end of the pipe q is J in. higher than the faucet end of the pipe p. Some Fig. 162. tradesmen level their pipes on the top outside, but that does not secure such correct- ness of level as levelling on the bottom inside of the pipes, because the pipes are not always exactly round. If ifc is wanted to give a fall of 1 in 36, then, with the B tJX-T ] -~1 c - --^^^^^m Fig. 163. levelling-rule at h raised | in., a piece of wood or a pin, to project 1J in., is put on at r. When jointing the pipes care has to be taken, while making them tight, not to leave any of the cement sticking up inside the pipes, at the joints. Of course the use of the access pipes, Figs. 145, 153, and 154, tends to safeguard that.