Welding is accomplished by electricity, on a large scale. Not only are ordinary masses of steel so made one, but the hulls, masts and yards of steel vessels are thus welded together electrically, so that there is no possibility of a seam “giving,” nor of a leak taking place. Steel bridge-members being similarly electrically welded together, the danger from such bridges giving way is reduced to an insignificant minimum. Primary batteries generate an electric current by chemical action upon coal, without the production of heat or odor; so that the steam engine is seldom needed, and, indeed, in many places as rarely seen as the wind-mill was in 1893. Horology, as of old, is one of the exact sciences; but we find upon every street, electrically-driven clocks telling to the tenth of a second the time of day or night; the twenty-four hour system having come into general use about 1900, and London time being kept in every city in the civilized world. The central stations of the telephone and other conveniences are worked by the subscribers themselves; the apparatus in each house enabling the subscriber to ascertain whether or not the person with whom he wishes to communicate is at liberty; and to connect with him if he is. All cities on the Continent are connected in a universal telegraphic and telephonic exchange, so that San Francisco can write, print or talk in New Orleans or Montreal. The telephone is so improved that it can be worked across the Atlantic, although the Pacific as yet defies all attempts of inventors to produce a system that will work without fail under all conditions. By this wonderful improvement Patti, from her castle at Craig-y-Nos; Campanini, from his beloved Italy, and other celebrated artists, could have delighted those who heard them in New York, by taking part in a concert together; but those great artists are but memories, and have been supplanted by others, with voices improved by surgery and special nurture until their range, delicacy and power have been brought to a degree of perfection of which the nineteenth century never dreamed. The chemists have not been far behind the electricians in their triumphs and successes. The subject of special plant foods has been, during the past forty years, taken up by agricultural chemists with such results that not only can any special plant be given its special food, but special portions of it can be developed in disproportion to the rest; thus, oranges and lemons can be grown without seeds, and dwarf wheat practically without any straw. New varieties of food-plants have been developed from wild plants, while fertilizers are employed to dissolve the rocks that are in the soil and render them at once absorbable by the plant roots.