Page:The American Cyclopædia (1879) Volume VIII.djvu/440

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426 IIAMM HAMMER time. At the same conference he was elected bishop, in which office he continued till 1852, when he resigned on account of ill health, in accordance with a principle that he had power- fully advocated in 1844, viz., that the episco- pacy of the Methodist Episcopal church is not an order, but an office. From 1856 he resided at Mt. Pleasant. Bishop Hamline's writings are largely devoted to the defence and illustration of the Wesleyan doctrine of sanctification. A collection of them has been made by the Rev. F. G. Hibbard, D. D. (" Works," &c., 2 vols., New York, 1871), who had previously edited a volume of his sermons (Cincinnati, 1869). See " Life and Letters of L. L. Hamline, D. D.," by W. C. Palmer (New York, 1868). IIAMM, a city of Westphalia, Prussia, at the junction of the Ahse with the Lippe, 20 m. S. S. E. of Munster; pop. in 1871, 16,914. As a point of military importance it suffered much during the thirty years' war. It was bombard- ed in 1761 and 1762 by the French, and dis- mantled in 1763. The old walls have been levelled and a promenade constructed in their place. It contains four churches, a gymnasium, manufactories of linen and other goods, tanne- ries, and a considerable trade. It is a central railway station between Hanover and Cologne. HA9IME, a town of Belgium, in the province of East Flanders, on the Durme, near its junction with the Scheldt, 17 m. E. by N. of Ghent; pop. in 1867, 10,142. The inhabi- tants are engaged in rope making and ship building, and there is a considerable trade in cloth and flax. In the neighborhood interest- ing antiquities have been discovered. HAMMER, a tool for communicating force by impact. There are three varieties, those which are moved by the arm, those which are moved by their own gravity, and those which are moved by compressed steam or other power. The two latter kinds are called power ham- mers. The first kind comprises small or hand hammers, and sledges. The hand hammer consists of a head, to give momentum, and a small helve or handle fitted into an eye, which is usually in the middle of the head. Their weight varies from an ounce to one or two pounds. Sledges are large hammers, to be wielded by both arms, and vary in weight from 2 to 20 Ibs. Large wooden hammers, bound with iron, used by woodsmen in driving wedges, are called beetles; smaller wooden hammers are called mallets. Power hammers are of various forms, moved by water, steam, and sometimes by horse power. The common forge hammer is made of a heavy head of iron, 5 to 10 tons in weight, faced with steel, and having a helve of cast or wrought iron, or wood, the centre of motion being at the end of the helve. The hammer is raised by cams upon a wheel, the lifting force being applied near the head. The force of the blow is the momentum attained by the mass in falling through a height of from 16 to 24 in. The speed is usually from 50 to 100 strokes per minute. Tilt hammers have much the same construction as the common forge hammer, except that the head is raised by depressing the opposite end of the helve by a cam wheel, as represented in fig. 1, the centre of motion being between the head and the point of appli- cation of power. They are lighter and move with greater rapidity, and are used for lighter kinds of work. Both kinds must be substan- tially supported by solid foundations. The steam forge hammer, in which steam is used as a propelling force to the hammer, patented by Mr. Nasmyth of England in 1842, and also by M. Creusot of France in the same year, is a much more efficient machine. Nasmyth's hammer is the one generally known. The hammer head is fixed to the end of a massive piston rod working vertically in a high-pres- sure steam cylinder, placed above, the whole being held in a strong iron frame having two standards. The hammer block weighs many tons, and must rest upon very strong and solid foundations, common to the whole. The lift or stroke of the hammer is from 5 to 9 ft., de- pending upon the size of the machine. The momentum will of course vary with the steam FIG. 1. Tilt Hammer. pressure and length of stroke, which, from the construction of the cylinder, may be varied to suit circumstances. A monster steam ham- mer of a construction similar to Nasmyth's is employed in Krupp's cast-steel works at Essen, Germany. The hammer head is 12 ft. long, 5J- ft. wide, 4 ft. thick, and weighs a little over 50 tons, and has a stroke of 9 ft. The depth of the foundation is 100 ft., consisting of three parts, masonry, timber, and iron, bolted to- gether. Four cranes, each capable of bearing 200 tons, serve the hammer with material. Smaller steam hammers of much higher speed are used in forging smaller articles, such as swords, scythes, axes, -carpenters' tools, steel bars, &c. One of these, exhibited at the Vienna exposi- tion in 1873 by Gustav Brinkmann and co. of Westphalia, is represented in fig. 2. While the frames of the large hammers have two stand- ards, this has only one, an advantage allowed by its smaller size. The admission of the steam is effected by a simple slide valve worked by a hand lever, as shown in the engraving. In this machine, in consequence of the manner in which the steam is admitted, the length of stroke is constant ; in this individual case, 7i in. The weight of the -hammer is 4 cwt., and