The Tides. Influence of the tides upon the history of the earth. Drilling Glass. * * * * * MACHINE TOOLS FOR BOILER-MAKERS. We give this week an engraving of a radial drilling machine designed especially for the use of boiler-makers, this machine, together with the plate bending rolls, forming portion of a plant constructed for Messrs. Beesley and Sons, boiler makers, of Barrow-in-Furness. [Illustration: IMPROVED BOILER PLATERADIAL DRILL.] This radial drill, which is a tool of substantial proportions, is adapted not only for ordinary drilling work, but also for turning the ends of boiler shells, for cutting out of flue holes tube boring, etc. As will be seen from our engraving, the pillar which supports the radial arm is mounted on a massive baseplate, which also carries a circular table 6 ft. in diameter, this table having a worm-wheel cast on it as shown. This table is driven by a worm gearing into the wheel just mentioned. On this table boiler ends up to 8 ft. in diameter can be turned up, the turning tool being carried by a slide rest, which is mounted on the main baseplate, as shown, and which is adjustable vertically and radially. For cutting out flue holes a steel boring head is employed, this head having a round end which fits into the center of the table. When this work is being done the radial arm is brought into the lowest position. Flue holes 40 in. in diameter can thus be cut out. The machine has a 4 in. steel spindle with self-acting variable feed motion through a range of 10 in., and the radial arm is raised or lowered by power through a range of 2 ft. 8 in. When the arm is in its highest position there is room for a piece of work 4 ft. high between the circular table and the lower end of the spindle. The circular table serves as a compound table for ordinary work, and the machine is altogether a very useful one for boiler-makers. The plate-bending rolls, which are illustrated on first page, are 10 ft. long, and are made of wrought iron, the top roll being 12 in. and the two bottom rolls 10 in. in diameter. Each of the bottom rolls carries at its end a large spur-wheel, these spur-wheels, which are on opposite sides of the machine, each gearing into a pinion on a shaft which runs from end to end below the rolls, and which is itself geared to the shaft carrying the belt pulleys, as shown. This is a very simple and direct mode of driving, and avoids the necessity for small wheels on the rolls. There is no swing frame, but the top roll is arranged to draw through between the arms of the spur-wheels, a very substantially framed machine being thus obtained. [Illustration: IMPROVED BOILER PLATE BENDING ROLLER.]