Possibly the building in which we work is a steel building, if not, it may be made of reenforced concrete and this form of construction is dependent upon the use of iron. The product toward which we are contributing our industry, whatever it may be, is dependent upon commerce, transportation, and communication; and these great branches of activity are dependent upon steel. Iron can be melted and cast into a thousand different shapes. It is used to make the most simple kitchen utensil and the largest and most complicated machinery. Again, it is melted in larger quantity, combined with carbon, and put through the rolling-mills. By this process it may become steel rails, or be made into plates and huge sheets that form the protective outer skin of the great ships of war. It is rolled out thin and corrugated to be used as sheeting for houses, and sides of freight-cars, and roofs of houses; or it may issue in things as delicate as knitting-needles or the finest springs which form the adjustment and motive power in the most costly watches. It is used in the construction of buildings that tower up hundreds of feet above the level of the street, and is the only thing that has been found so far that can be used successfully for such a purpose. At the same time this most necessary substance is formed into pliable rope and used to draw the miner and the minerals he mines from the depths of the earth, and to keep the elevators running up and down in hotels, office buildings, and apartment houses. The finest cambric needles are first cousins to the great guns with which the Germans were able to shell Paris from a distance of seventy-five miles.