The Useful Arts Employed in the Construction of Dwelling Houses. Second Edition

by Anonymous

The more recent attempts to gain the same object by means somewhat similar have been very numerous; some of which we may here notice as examples of the whole.

An American patent was granted in 1837 to a Mr. Louis Pambœuf, for the invention of a fire-proof paint. The mode of preparing it is thus described. A quantity of the best quicklime is selected, and slacked with water in a covered vessel; when the slacking is complete, water, or skimmed milk, or a mixture of both, is added to the lime, and mixed up with it to the consistence of cream. When milk is not used a solution of rice paste is employed, obtained by boiling eight pounds of rice to every hundred gallons of paint. When the creamy liquor is prepared, alum, potash, and common salt are added, in the proportion of twenty pounds of alum, fifteen pounds of potash, and a bushel of salt, to every hundred gallons of the paint. If the paint is to be white, six pounds of prepared plaster of Paris and the same quantity of fine white clay are added to the above proportions of the other ingredients. All these ingredients being mingled, the mixture is strained through a fine sieve, and then ground in a colour-mill.

When roofs are to be covered, or when crumbling brick walls are to be coated, fine white sand is mixed with the paint, in the proportion of one pound to ten gallons of paint; this addition being made with a view to giving the ingredients a binding or petrifying quality. In applying this paint, except in very warm weather, it is prepared in a hot state; and in very cold weather precautions are necessary to prevent it from freezing. Three coats of this paint are deemed in most cases sufficient.

In another variety of this paint oil is the chief liquid ingredient. To prepare it forty gallons of boiled linseed oil are mixed with slacked lime to the consistence of a paint; and to this are added two pounds of alum, one pound of potash, and eight pounds of common salt; or good wood-ashes may be substituted for the potash. This paint is used in the same manner as other paint; and any colour may be obtained by adding the usual pigments to the composition.

The preparation of a kind of paint containing alkalies seems to have been a favourite measure among inventors of “fire-proof” composition; for many of the modern projects have had this for its basis. But in most cases there have not been means for determining the degree of efficacy possessed by these compositions. There were, however, a few years ago trials made of rather an interesting character, which were described in the public journals, and which were of the following nature.

In 1838, a company was formed for the sale and use of a composition of this kind, and an experiment was made in the Clapham Road to show its efficacy. The house, which was a small one, had been built in the usual way, with the intention of being fitted up in the ordinary style. While yet a mere shell, all the boards, timbers, floors, ceilings, stairs, and wood-work generally, were coated thickly with a greyish or slate-coloured composition, which dried to a state of great hardness.

On a particular day the upper floor was covered with shavings in great abundance, to which a number of deal planks were subsequently added. The first floor front room was fitted up as a chamber, with bed and furniture, chairs, tables, &c., as nearly as possible in the usual style. The shavings and wood on the upper floor were then kindled, as were also planks and shavings placed on the floor of the furnished room. The consequence of this was that the two rooms speedily exhibited a blaze of light: the whole of the furniture (purposely selected of an inexpensive kind) being ignited. The flames burst from the windows; but although the entire contents of the room were consumed, the fire did not communicate to the floor above, nor to that beneath, nor even to the other room on the same floor. Several small parcels of gunpowder were introduced between the ceiling of the burning room and the floor of the room above it; but they did not ignite; nor were the other parts of the house injured in any material degree.

Another trial took place at the White Conduit Gardens; where two close wooden buildings, of the size and shape of sentry boxes, were placed in the grounds. One of them was coated on the inside to the thickness of about an eighth of an inch with the composition, and was also partially covered on the outside; while the other was left in the plain wood state. A flooring was placed at about the centre of each of these, and through the holes in front shavings were put and then ignited. The box which was not coated with the composition was soon in flames; while the fire in the other went out without having had any effect upon the general structure. The building which was in flames was then placed contiguous to the partially-coated outside of the other, and although it was not materially injured, the exterior coating peeled off in some places, and the wood became charred; the interior, however, appeared perfectly uninjured by the flame.

If the results of these experiments were really such as the description would seem to imply, it might excite surprise how it happens that no practical results have followed. But there are always numerous reasons why an experiment, which succeeds under circumstances made for the occasion, should not be available in practice; and it is probable that some such discordance may exist here. Perhaps the mode in which we may more consistently look for the practical attainment of the object in view is by the adoption of some improved mode of building, in which either wood is not employed at all, or, where sparingly used, measures are taken to shield it from the action of fire. One such method is Leconte’s, described as follows.

This plan consists in the employment of iron frames to receive concrete matter for forming the walls. The basement story of the building is constructed according to the ordinary methods up to one foot or more above the ground. On the basement so constructed is to be erected the patent wall, formed of frames entirely of cast-iron, in one or more pieces, or a combination of cast-iron and wrought-iron plates. These frames are to be set one on the other until the required height is attained, the necessary stability being obtained by means of steady pins at the corners of one frame fitting into holes made in the corners of the frame which is opposed to it. Suitably-shaped frames are employed for the internal partition walls, and for doorways, window-frames, &c. The flues of the chimneys are formed of iron or other metal pipes, placed in the thickness of the walls. When the required elevation is obtained, a concrete of any suitable material is poured into the framing, and fills up the vacant space, giving firmness and solidity to the structure; the concrete being made of gravel and lime. To give steadiness, lead is to be introduced between the joinings of the iron-work. The doors and window-frames are to be fastened to the walls by any of the usual known methods. The main beams and cross beams of floors and roofs may be of cast-iron, or formed of iron and wood; or they maybe formed of one or more pieces of plate-iron, bent up into an oval form, and straightened by an iron or wooden bar passing through them lengthwise, the upper edges of the metal being turned over to increase the strength. In the interval between the beams there are to be iron rods running in various directions, and supporting a metallic wire-work, which forms the foundation for the ceiling. Similar wire-work is to be employed in lieu of laths for plaster surfaces. All the iron-work is to be painted over with some suitable composition to prevent oxidation.