Page:Popular Science Monthly Volume 38.djvu/612

594 with such establishments, it will require but a slight effort of the imagination to impart to the picture all the attributes of real life; and to fill the sooty air with the hissing of steam, the jigging jingle of coupling-boxes and spindles, and the groaning of rolls, among which sounds are injected the resounding blows of a steam hammer, answered by the clattering scream of a "cutting-off saw," mingled with the hum of revolving wheels, and scores of minor sounds and reverberations; over all, the lurid glare of furnaces and hot iron, amid which the busy workmen move in orderly activity at the work in hand; the whole making a scene in which the strength of man and iron, the energy of fuel and fire, and the power of steam and machinery are combined as in no other industry on the surface of the round world. The rolls for making heavy bar iron of a rectangular section, hitherto described, have been provided with a number of "grooves" or "passes" of varying dimensions suited to the sizes of the bars required; but the manifest objection to this very common arrangement is that, in order to be able to produce a large variety of bars, a great number of rolls must be kept in stock. But the mill represented in Fig. 48 is so contrived that it will roll an almost unlimited number of sizes of rectangular bars by the use of a combination of four plain cylindrical rolls, two of which revolve on horizontal axes, and the other two on vertical ones. In the figure, for the purpose of clearness, the driving mechanism of the vertical rolls is omitted. Each of the pairs of rolls is driven at an appropriate velocity, and is adjustable, so as to adapt their relative positions to the particular cross-section of bar about to be made. The horizontal rolls can be adjusted vertically and the vertical rolls horizontally, and therefore any proportion of width and thickness can be turned out, up to the limitations imposed by the width of the cylindrical portion of the horizontal rolls and the length of the body of the vertical rolls. This highly ingenious mechanical combination was invented by Herr Daelen, a German engineer, and it was first erected