Henry C. Flacke

An essential point in obtaining a strong spark is that a good contact shall be made before the contact points are forced apart.

In practically all make and break igniters, the movable electrode passes through an iron or a bronze bushing and the current must pass from this bushing to the axis of this electrode before reaching the contact points.

Under certain conditions the contact between the outer stem and its bearing, i. e., with the metal of the engine, may be so poor that only a small current could flow; so that on breaking the contact the spark is too feeble to light the gas.

Oftentimes when this condition exists it can be seen by shielding the igniter mechanism from the light. If "the contact between the igniter stem and bearing is poor, small sparks may often be noticed around the igniter parts outside of the cylinder.

The cause of this trouble may be due to the presence of too much oil on the igniter bearings; it is, however, more often due to wear and a poor fit between the stem and its bearings; for where the bearing is poor the gases and burnt oil flow through and by reason of the high temperature which the stem reaches after a few minutes running, the oil and soot bakes on it, forming with the "fire rust" a coating that is an -extremely poor conductor.

Add to the resistance thus offered, that due to the accumulation of fresh or of burnt oil on the contact points proper inside the cylinder, an amount of resist ance is easily reached which prevents the passage of •enough current to give a satisfactory spark.

When the stem is flooded with oil a good contact is not formed for the current, as oil is a poor conductor, and when it completely surrounds the stem the insulation is absolute. Yet when well oiled the igniter works better than when the bearing is dry. The prevention of the loss of this oil and the keeping of the bearing in good condition could be obtained by making a valve shoulder near the outside end of the bearing or by surrounding the outer end with a stuffing box and lastly a perfect metallic contact should be had - either by soldering a flexible wire direct to the igniter stem - or to a copper brush pressed against the stem at its extreme outside end. Where such provision is properly made it will be found that an ample spark for all purposes can be furnished with from one-shird to one-half the battery power usually found to be necessary. - "Gas Power. "

The cost of a kilowatt-hour of current delivered at the switchboard of any of the larger central stations will not get much below one-quarter of a cent. For the larger New York stations, the figure is around .26 of a cent, and it probably will not go much over one cent for a small non-condensing station.

In many houses and offices, at certain seasons of the year, gas fire-place logs are used for heating purposes. After being used for several seasons, however, these logs lose their efficiency, fail to radiate heat properly and give off objectionable odors of the gas. Users frequently wonder at the cause of these troubles, call in a plumber who looks at the connections and generally goes away without making proper repairs. He fails to locate the trouble which, in a majority of cases, is the wearing off of the asbestos covering.

When newly purchased, the asbestos fibres are quite long, from one to one and one-half inches in length, but after being used for a while they become broken and even entirely worn away in places. The gas, in such a case, instead of heating these fibres to incan-desence and radiating its beat therefrom, passes away into the air more or less unconsumed, and failing to give the maximum heat.

To remedy this condition, take an old knife or putty knife and scrape off all the asbestos from the face of the log. Get about a pound and one-half of asbestos wool, which will be sufficient, for a large surface. Then get about a pint (or pound) of silicate of soda, which, like most everything you buy at a drug store, costs about a dollar an ounce, or fifty cents a gallon ; the more you get the cheaper it comes. However, ten or fifteen . cents is a fair price for what is wanted. This silicate of soda is a mucilage, and is used to stick the asbestos to the fire face. Pour a saucerful of it and spread your asbestos out on a paper ready for use. With the fire surface cleaned, take a brush and cover the whole surface of the iron with a coat of silicate, using care to keep your hands clean and dry. Pick up a pinch of asbestos and dip it lightly in the dish of silicate and, beginning at the top of the log, stick it on, being careful not to cover up the small flame or gas holes. Repeat this, pinch after pinch, in a row across the top, then another row just beneath, and so on across the plate, row after row from left to right and top to bottom until the whole surface is covered. Put the asbestos on thick; the thicker you can get it on and still have it stick, the better. Now after it is all on you can turn on and light the gas; you need not wait for the silicate to dry. Heat cannot hurt it. Wherever gas flames come through the little holes, open them with a pointed wire or sharp needle. After the silicate is dry the loose fibres of asbestos can be shaken off by lifting the log from side to side.