Among its advantages may be named the four following points. Matches are not needed in making a light. Thus the danger from accidental fires, which have so frequently occurred from the careless use of matches, is avoided. Very little heat results from an electric light, while from kerosene lamps and gaslight much heat is produced. In warm weather this freedom from heat is agreeable. The burning lamp and the gas jet make the air of the room impure and unfit for breathing. This is not true of the electric light. In the use of kerosene and of illuminating gas there is frequently danger of explosion. Not so with the electric light. It will be seen that we are thus using to-day for lighting purposes occasionally the candle, quite largely the kerosene lamp, and to a great extent in towns and cities the gaslight, and best of all--the cleanest, the neatest, giving the brightest light, requiring the least attention from the consumer, and manifesting the highest development of man's inventive genius thus far--the electric light. Here at present man's invention in this direction has stopped. What the next step will be, no one can tell. Slowly through the ages man has been developing. Gradually he has grown in mental power and advanced morally and spiritually. It is very clear that although he is an animal and has the nature and desires of an animal, he has high mental capacity and is endowed with a spiritual nature, a soul. At the very beginning of creation we are told, "God said, Let there be light: and there was light." How and whence it came we cannot tell. It would almost seem that man in his effort to create light has kept step with his own development. The first light was produced from the simplest substances, solids: wood on the hearth, the pitch-pine knot, and the candle. Then followed light produced from liquids: olive oil, whale oil, refined petroleum. Afterward the inventive genius of man extracted from coal an invisible gas which would burn and give a bright, clear light. Rising higher and higher, man soars above all solids, liquids, and gases, and with a sudden bound leaps almost out of the realm of matter and produces the electric light, which is merely a form of motion. How clearly the progress of man, his elevation, his civilization, his increased conveniences and luxuries of life are made to appear in this study of his methods of obtaining artificial light! CHAPTER VII. LIGHTHOUSES. We have seen that artificial light is needed at night not only in houses, churches, and public halls, but also in the streets of large towns and cities for the benefit of those who have occasion to travel after dark. Still further, it has been found necessary to light the shores of the great sea, so that vessels may not run upon the rocks in the darkness and be stove to pieces.