hide Matching Documents

The documents where this entity occurs most often are shown below. Click on a document to open it.

Document Max. Freq Min. Freq
Knight's Mechanical Encyclopedia (ed. Knight) 17 1 Browse Search
View all matching documents...

Browsing named entities in Knight's Mechanical Encyclopedia (ed. Knight). You can also browse the collection for Moses G. Farmer or search for Moses G. Farmer in all documents.

Your search returned 9 results in 6 document sections:

Knight's Mechanical Encyclopedia (ed. Knight), D. (search)
er rests on the wheel. As the key rotates, while it passes over the metallic portion of the wheel, the circuit is complete, and when it passes over the non-conconducting portions i i of the wheel the circuit is broken. Thus are signals given in Farmer's firealarm telegraph. Steam-gage dial. Another form of telegraph-dial is the lettered and number dial of the Cooke and Wheatstone telegraph, in whose center a pointer rotates or oscillates, and directs attention of the observer to the leto current in transmitting across the bridge x z, in which the relay or receiving instrument is placed. The larger portion of the incoming current, however, passes through and actuates the relay, as it offers the path of least resistance. Moses G. Farmer, of Boston, invented a duplex system in 1858, in which he used a key which preserved the continuity of the circuit, and also reversed the battery at the sending station, this reversal making the signals at the distant station, the relay bein
Knight's Mechanical Encyclopedia (ed. Knight), F. (search)
the latter under charge of one of the Siemens brothers. These systems simply connected a series of watch-towers, wherein watchmen were stationed, by an ordinary Morse line, so that the watchmen could telegraph to each other the locality of a fire. The present system is that of Farmer and Channing, American patent of May 19, 1857. Mr. Channing first devoted his attention to this subject in 1845, and published several articles that year attempting to show its feasibility. In 1848, Mr. M. G. Farmer invented a method of ringing bells by electricity, and in an experimental trial that year the bell in the tower of Boston City Hall was rung by an operator in New York. In 1851, Boston appropriated money to build a fire-alarm telegraph, and early in 1852 the line was completed, put in operation, and proved a success. That system is still in use, the improvements being in the mechanical devices for carrying it into effect. It comprised a central station, a series of signalboxes
Knight's Mechanical Encyclopedia (ed. Knight), G. (search)
lts has been very generally employed, and latterly iron similarly coated has been used. In the Austrian section of the Paris Exposition of 1867 there was exhibited a battery on the Smee principle, in which the positive element was fragments of amalgamated zinc, and the negative lead coated with platinum. This is said to be used in the Austrian telegraph-offices. Weak sulphuric acid is used as the bath in this battery. A very permanent battery of low intensity has been devised by M. G. Farmer of Boston. It consists of an oval copper vessel forming the negative element, and which is nearly filled with a saturated solution of sulphate. At one end is a porous cup within which is placed a smaller porous cup, which receives a cylinder of amalgamated zinc. The interior porous cup contains pure water, and the exterior cup a weak solution of sulphate of copper. The saturation of the liquid in the outer copper vessel is maintained by placing at the opposite end a third porous cup
Knight's Mechanical Encyclopedia (ed. Knight), L. (search)
portance. It should preferably be placed on the west side of the building in this latitude, and especially on that chimney from which a current of air ascends during the summer season, and should be connected where practicable with the water or gas pipes of the street. Where this is impracticable, connection should be made with a well always containing water, or with an iron plate buried in the ground. This rod may be put up by an ordinary blacksmith. The lightning-rod invented by Moses G. Farmer of Boston is formed of a core of steel, which is first carefully tinned and then covered with copper, after which the compound wire is tinned, to prevent rusting. Lightning — rods for powder-magazines were formerly erected on a mast at a short distance from the building. It is now thought advisable to attach them directly to the building in the following manner: A strip of copper is secured to the ridge of the building, at each end of which is a lightning-rod, of 1/2 inch copper, pr
Knight's Mechanical Encyclopedia (ed. Knight), M. (search)
e manufacturers in laying off the dress on the face of stones. See Millstonedress. Min-ar′gent. Copper, 1,000; nickel, 700; tungsten, 50; aluminium, 10. The first three ingredients are melted together, then run off in a granulated form, and again melted, adding the aluminium and about 1 1/2 per cent of a flux composed of one part borax and one part fluoride of calcium; these proportions of borax are reduced as the fusion proceeds. It is one kind of aluminium bronze. (See list of Farmer's aluminium alloys, page 71.) In these copper is the first metal, aluminium the second, and silver, iron, nickel, and zinc in various combinations, so as to give the desired character to the metal, according to its intended duty. A number of other jeweler's alloys are to be found in a table on page 63; white-metal alloys on same Millstone-ventilator. page; alloys under specific names may be found in the list under metallurgy. Mincing-knife. Minc′ing-knife. A knife with a curv
Knight's Mechanical Encyclopedia (ed. Knight), T. (search)
finger to establish an electric circuit. See Morse alphabet, b, Fig. 3225, page 1476. Farmer's magnetic telegraph. Fig. 6251 shows a key in connection with Farmer's magnetic telegraph for sending messages simultaneously in opposite directions upon a single line of telegraph. Upon the receivingmag-net is a single set of coicrude rosin, 1/4 lb.; spirits of turpentine, 1/2 gall; boiled linseed oil, 1 gill; umber, 2 oz. Successive layers of the fiber and compound may be applied. Moses G. Farmer's telegraph-wire is formed of a core of steel, which is first carefully tinned and then covered with copper, after which the compound wire is tinned, to preves name is yet associated. The workshop in which the many ingenious contrivances to perform this work with speed were invented may be Arrangement of tools in a Farmer's tool-house. said to have been the training-school for the early machinists, whose labors have, within the present century, built up the mechanical greatness o