The size of the cup may be from three inches to three and a half in diameter, and about five inches high. The opening at the bottom may extend about half of the height. The lamp is made of less diameter than the interior of the cup to admit of moving to get a good flame from the blow-pipe. The lamp may be 1¾ inches in diameter and an inch high. The boiler is about two inches high and has the bottom made a little convex, as shown by dotted lines, and is some smaller than at the top where a flange is formed to admit of its resting on the top of the cup. The top of the boiler is also convex, and has a short tube in which a cork is fitted, for the purpose of filling it. The blowing tube is about three-sixteenths of an inch in diameter. There is a long slot in the cup near its handle which readily admits of its being put in position for blowing. There are several small holes near the top of the cup to insure draft to the lamp, and there is a large hole about an inch in diameter opposite the end of the blow-pipe through which the flame issues where the work is held. For silver soldering, small brazing, tempering, or any similar small work, this lamp is most excellent. To make the small blowing-pipe, drill a smooth hole through a piece of iron or steel and ream out one side of it. Cut a strip of thin copper or soft brass of a width just enough to fill the hole if it were made into a tube. Point one end of the strip and roughly form it into a tube, insert in the hole and pull it through. Or the strip can be rolled around a piece of iron wire forming it to a tube by hammering. Soft solder it after being formed to shape. _Breech Wrenches._—In many shops the monkey wrench is made to do duty in removing breech-pins, but at the expense of marring the pin where the wrench engages it. If many guns with breech-pins like those used in army guns are handled, it is worth while to have solid wrenches forged of iron like Fig. 12. The length may be about fifteen inches, with an opening to fit the shoulder of the breech-pin. The width at this place may be about one and a half inches; thickness, about half an inch; diameter at end of handle, about three-quarters of an inch, and at the small portions near the centre, about half an inch. [Illustration: FIGURE 12.] A wrench for removing patent breeches or nuts from double guns is made like Fig. 13. It consists of a steel bar about fifteen or sixteen inches long and about three-quarters of an inch diameter. At a little to one side of the center is fastened a steel collar that has four projections made at one end. A similar piece is fitted opposite to it, but is made to move back and forth to fit the work by means of a screw that is formed behind where it is fitted. A slot is made in the extension of the piece and a key fitted to prevent its turning around as the nut is turned to advance it toward its fellow piece.