concrete. Must never be placed on any unstable box, bench or other stand.

Stoves Burning Oil-Kerosene Oil Pressure Systems-(Na-| tional Board of Fire Underwriters).-Stoves, water heaters or open burners must be supported on a substantial frame or stand relieving the piping from all unnecessary strain. Proper protection must be provided to prevent overheating or ignition of adjacent materials. Enclosed stoves must be provided with a suitable chimney connection. Must have a readily accessible Must be provided with a metal

shut-off and regulating valve. pan, made tight without solder, and placed beneath the burner. Must be marked with the name of the stove and of its manufacturer.

Stoves burning oils and other burning fluids should be placed the same as gas stoves and, where possible, should have a metal pan under them of a capacity in excess of the oil reservoir of the stove, but stoves should not stand low enough in these pans to cut off air drafts under them. Oil stoves are not recommended for use, and should be discarded wherever possible.

Sulphur furnaces at acid works to be of brick, at least 5 feet from wooden sides of woodwork of any kind of the acid chamber, and, if of iron, to have a solid brick wall of not less than two-brick thick intervening; wall to rise not less than 3 feet above top of furnace. Floors of furnace room to be of earth, brick or stone. Roof of furnace room to be of non-combustible material, and at least 15 feet above top of furnace. (S. E. T. A.) Sulphur-burning rooms of sulphite pulp mills should be entirely of brick, but where there is any wood in the construction it must not be in such proximity to the burning sulphur as to render it liable to ignition.

NOTES.-All heating appliances passing through floors or roofs (such as cupolas, glass furnaces, etc.) must have a space around them clear of any wood, where passing through same, of at least 10 inches. This space can be covered by a metal hood or heavy iron, not in absolute contact with the heating appliance. Flues, gas conveyors, etc., to be treated the same as boiler breechings, etc.

Hot air or gas pipes (as in acid works, from burners, etc.,) to be treated the same as steam pipes or smoke pipes.

Heating devices on machines (as on stitching machines in boot and shoe factories) should use only steam, gas by an improved system, or kerosene oil in metal lamps. Steam for heating to have the preference.

Gasolene, naphtha and benzine-heated appliances should be discarded.

Woodwork directly exposed to any heating appliance should be closely covered with asbestos, overlaid with sheet tin (locked joints), following all lines and angles of the wood. Where the woodwork is not directly exposed to any heating appliance but apt to be overheated by it, should be protected by a metal shield having a clear air space on each side of it.

Special care and attention should be given to the oversight of all heating appliances; (first), to see that they are safely located and on good, substantial supports; (second), to see that they are well constructed, and where bracing or "tying" is necessary that the braces, anchors, rods, etc., are strong and well placed; (third), that they are kept in good condition, not used when broken or in any way in disrepair; (fourth), when fires are not needed that the appliances are left cold.

CHAPTER V.

LIGHTING.

ACETYLENE GAS MACHINES.-The installation of these machines is regulated by the local authorities in certain districts. (National Board of Fire Underwriters.) The use of liquid acetylene or gas generated therefrom is absolutely prohibited. The generator must be located in a well-ventilated room, in such a position that the operating mechanism shall have room for free and full play, and can be adjusted without the need of artificial light, and where there will be sufficient heat to prevent water from freezing. In no case shall it be nearer than 15 feet to any fire and 10 feet to any artificial light; it must never be placed in closets or where it will be subject to interference by children or careless persons, and if for this purpose further enclosure is deemed necessary, the enclosure shall be made of slatted partitions, permitting the free circulation of air. The generator must be set so that it is level, and so that unequal strain will not be placed on it or its connections, and if possible the foundation should be of brick, stone, concrete or iron, but if this is not possible and wood is used, it shall be of heavy planking, joist or timber, so arranged that the air will circulate about it, but whatever is used for a foundation must be firm and rigid. Each generator must be provided with an escape or relief pipe of at least 3/4-inch internal diameter; this pipe must be substantially installed, without traps, and so that any condensation will drain back to the generator; it must be carried to a suitable point outside the building and terminate in an approved hood, located at least 12 feet above ground and remote from windows, the hood being constructed in such a way that it cannot be obstructed by rain, snow, ice, insects or birds. The capacity of the generator must be such that it will be capable of supplying gas continuously for at least five hours for all burners attached, and must be great enough to furnish gas continuously for all lights supplied and for the maximum lighting period; generators for

conditions of service requiring lighting periods of more than five hours must be of sufficient capacity to avoid recharging at night. The following ratings will usually be found advisable:

I. For dwellings and where machines are always used intermittently, the generator should have a capacity sufficient to supply all of the burners attached.

2. For stores, opera houses, theaters, day-run factories, and similar service the generator should have a capacity of from 30 to 50 per cent in excess of the total capacity of the burners.

3. For saloons, all night or continued service, the generator should have a capacity of from 100 to 200 per cent in excess of the total capacity of the burners.

A small generator should never be installed to supply a large number of lights, even though it seems probable that only a few lights will be used at a time. An overworked generator adds to the cost of producing acetylene gas.

The carbide charge must be sufficient to furnish gas for all burners during the maximum lighting period; in determining charges the carbide to be estimated as containing 41⁄2 cubic feet to the pound, and the burners as consuming at least 25 per cent. over rated burning capacity.

Burners consuming one-half of a cubic foot per hour are considered standard in rating generators.

Piping must be so arranged that any moisture will drain back to the generator, but if from necessity any low points occur they shall be drained through tees into drip cups; tees must not have any pet cocks but must be closed with screw caps or plugs. A valve and by-pass connection shall be provided from the service pipe to the blow-off for removing the gas from the holder, in case it should be necessary to do so. The scheme of pipe sizes for piping from generators to burners should conform to that coinmonly used for ordinary gas, but in no case shall the feeders be smaller than 3%-inch. The following schedule is advocated:

Three-eight-inch pipe, 26 feet, three burners; 1⁄2-inch pipe, 30 feet, six burners; 34-inch pipe, 50 feet, twenty burners; 1-inch pipe, 70 feet, thirty-five burners; 14-inch pipe, 100 feet, sixty burners; 11⁄2-inch pipe, 150 feet, one hundred burners; 2-inch pipe, 200 feet, two hundred burners; 21⁄2-inch pipe, 300 feet, three hundred burners; 3-inch pipe, 450 feet, four hundred and fifty

burners; 31⁄2-inch pipe, 500 feet, six hundred burners; 4-inch pipe, 600 feet, seven hundred and fifty burners.

In all cases it is desirable that generators be located outside of the buildings insured, and in cases of very large installations and in territory where underwriters having jurisdiction do not permit installation inside insured buildings, the following specifications are offered as suggestions for generator houses: In closely built-up districts generator house should be of brick, fireproof, and located as far as practical from other buildings; it should not open into or towards the insured buildings, and should be kept under lock and key; the dimensions to be no greater than the apparatus requires to allow convenient room for recharging and inspecting all its parts; the floor should be at least 12 inches above grade and the entire structure thoroughly weather proof and thoroughly ventilated, and if necessary to heat it, the heat should be supplied by steam, hot air or hot water. In outlying districts where the generator house can be located 25 feet or more from other buildings, fireproof construction is not especially necessary:

The following are necessary for the proper care and attention of the machines, etc.:

Generators designed to supply the rated number of burners for a longer period than five hours should be cleaned and recharged at regular stated intervals, regardless of the number of burners actually used.

Generators not intended for use throughout the entire year shall have all water and gas removed at the end of the season.

It is usually necessary to take the bell portion out and invert it so as to allow all gas to escape. This never to be done in the presence of artificial light or fire of any kind.

A regular time should be set for attending to and charging the apparatus during daylight hours only.

In charging generating chambers clean all residuum carefully from the containers and remove it at once from the building. Separate the unexhausted carbide, if any, from the mass and return it to the container, adding new carbide as required. Be careful never to fill the container over the specified mark, as it is important to allow for the swelling of the carbide when it comes in contact with water. The proper action and economy of