r i r c: the most remarkable experi- ments I r with the result ur ittended th< m. Dr. 1 1 1 1 ted a pi mi ■ ■;■' bouses rhe th n mid )- laid mi the floors, the gn ater is I '.ur:: | . 1 [e supposes that the d ptli of an incb will be an sufficient; though he recommends to lav a do per coal on the st.iirs ; because lire in general, ascends by means of stair-cases with the g est velocity. A patent was granted in April 1773) to David Hartley. Esq. of Golden-square, for Ins method of securing buildings and ships against lire. See our first vol. p. 385. Lord Mahon has likewise in- vented a ery simple and effectual mode of securing every kind of building against all danger of fire : he divides it into three parts, name- ly, under-flooring, extra-lathing, and inicr-sccm-big. The first part or method, is either single or double, in single under-flooring, a common strong lath, one quarter of an inch thick, should be nailed against eacb side of every joist and main-timber, supporting the floor which is to be secured. Similar laths are then to be nailed on the whole length of the joists, the ends of which abut against each other. The top of each lath or fillet, on; ht to be an inch and a half below the top of the joists or timbers, against which they are naiied, so as to form a small ledge on every side. When these fillets are nailed on, the}' should be laid in a rough plaster, which ought to be spread on the tops of such fillets, so as to leave no vacant space between them and the joists. Short pieces of common hrths are next to be nailed closely I R [281 her, in a direction contrary to thai od the 1 ■■-x^ ; the ends of the . r are to rest on the filletSj and to he well bedde i in rough .■. bul not fastened with 11a 1 . 'I be) are next to be a at< I am a with the plaster, which is to be spread over them to the tops of the joist .. In double-flooring, the 1 and short pieces ot laths are applie.l in the manner already de- scribed; the coat of- rough plaster ought, however, in this method, to be somewhat more than half as thick as that in single-flooring. — While the rough plaster is laying on, some additional short pieces ot laths are to be inserted between the joists upon the first coat, as close- ly to each other as possible, and in the same direction as the tirst layer of laths. Over this second layer of short laths, another coat of rough plaster should be spread, which ought to be trowelled level with the tops of the joists. As soon as the plaster-work be- tween the joists is perfectly dry, it should be inspected, in order to ascertain whether there be any small cracks, especially next to the joists. Should any occur, it will be requisite to close them, by washing them over with a brush, wetted with mortar- wash, which may be prepared by mixing two measures of quick-lime and one of sand in a pail, and tempering the whole with water, lili it acquires the consistence of a thin jelly. Previously to laying down the flooring-boards, a small quantity of dry common sand should be strew- ed over the plaster-work, and struck smooth with an hollow rule in the same direction as the joists are laid, so that it may lie rounding be- tween each pair of joists. Particu- lar attention should be paid to the plaster*
