Gas-lighting has, of course, its limitations. It is not adapted for use beyond the range of cities or towns whose populations are sufficient to warrant the large expenditures necessary for gas plants. It is a special rather than general light. Yet within its limited domain of use it has proved of wonderful utility,—a source of cheer for millions, a clean, safe, and economic light, a convenience far beyond the candle, the lamp, or any previous lighting appliance. In the street, it is a source of safety against thieves and way-layers. In the slums, it is both policeman and missionary, baffling the wrong-doer, exposing the secrecy that conduces to crime, laying bare the hotbeds of shame. It is as well a source of heat as light, and consequently convertible into power for light mechanical purposes. In the kitchen, it is more and more becoming a boon to the housewife, who by means of the gas range escapes, in cooking, much of the dust, smoke, worry, and even expense of the coal cook stove and range. In the parlor, library, or sick-room, it is a cheerful and effective substitute for the coal grate, and may be made to assume the cosy qualities and fantastic shapes of the old-fashioned wood fire. Coincident with the discovery of petroleum, its inseparable companion, natural gas, came into prominence as a source of both light and heat, or this became true, at least, after it was ascertained that natural gas regions existed which could be tapped by wells, and made to give forth their gaseous product independent of the oil that may have at one time existed near or in connection with it. This natural source of light and heat became as interesting to the geologist, explorer, and capitalist as the source of petroleum itself, and soon every likely section was prospected, with the hope of finding and tapping those mysterious caverns of earth in which the pent-up luminant abounded in paying quantities. It was found that workable natural gas regions were numerous in the United States, especially in proximity to petroleum or bituminous coal deposits, and little time was lost in their development. As if by magic, a new and profitable industry sprang into existence. The natural gas well became almost as common as the oil well, and at times far more awe-inspiring as it shot into space its volcanic blasts which, when ignited through carelessness, as sometimes happened, carried to the vicinage all the dangers and terrors of Vesuvius or Stromboli. Powerful as was the force with which natural gas sought its freedom, wonderful as was the phenomenon of its escape from the subterranean alembic in which it was distilled, human genius quickly harnessed it by appliances for conservation and carriage to places where it could be utilized. Sometimes great industries sprang up contiguous to the wells; at others, it was carried through pipes to cities many miles distant, where it became a light for street, home, and store, and a prodigious