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action acts alarms apparatus armature arrangement attached axis battery becomes bobbins brushes cable carbon carbon-holder carries cause cell circuit closed coil commutator conductor connected consequence consists construction containing continuous copper core cylinder derived described diameter direction disks distance dynamo effect electric light electro-magnet exhibited experiments figure fixed follows force four frame give given Gramme heat incandescent increase insulated intensity iron lamp latter length less lever lower luminous machine magnet means mechanism metallic meters mines motor mounted movable move movement necessary obtained opposite pair passes pieces placed plates platinum poles position prevent principle produced quantity range regulator resistance rest revolving ring screw seen separated shown in Fig shows side Siemens solenoid spring terminal thick torpedo traverses tube turn upper vertical weight wheel wire wound zinc
Page 211 - Fio. 18. of eight laminae of steel. The distance apart of the two limbs of each magnet, as well as the distance between the north pole of one magnet and the south pole of the next, is precisely equal to the distance apart, or pitch around the armature, of the pole-pieces and the coils. The details of the magnets, and their method of adjustment and attachment, are shown in Figs.
Page 208 - These springs, pressing on two contacts under the lamp, make the appropriate connections. The regulator itself is a combination of the Serrin and Berjot lamps. It comprises the two electro-magnets of the latter lamp, the armatures of which form an internal core, — one magnet having coarse wire, and placed direct in the circuit ; the other having fine wire, and mounted in a derived current. The former acts on the articulated frame carrying the lower carbon ; the latter acts on the disk brake controlling...
Page 191 - Report of Engineer Department of the Philadelphia Exhibition " (1884) : " Electrical Appliances of the Present Day" (New York, 1884); and "Ancient and Modern Lights
Page 127 - ... by means of the contact rollers, r and r, between the guide rods, D1 and D, the contact being maintained by the spring, s (Fig. 14). Sometimes a permanent electrical connection is made by a loop of wire attached to the rods, D, and holder, H. If a fixed focus lamp is required, the pulleys, R and R1, are made double, one being twice the diameter of the other ; the cord that passes over the larger pulley being connected to the top electrode, whilst...
Page 81 - ... the ray traverses twice the thickness of the mirror before taking its final direction. Now, these two surfaces are not parallel, the interior surface being a sphere having a different radius than the other, or in other words the mirror is a concavo-convex lens with the centre thinner than the edge. The different thicknesses which the various rays have to traverse, according to the angle which they make with the axis, so modify them as to bring them rigorously parallel if the radii of the two...
Page 154 - The following are the principal passages from this patent : The invention has for its basis the use of metallic conductors, or of continuous carbons, heated to whiteness by the passage of an electric current. The best metal for this purpose is platinum, the best carbon is retort carbon. When carbon is employed, it is useful on account of its affinity for oxygen at high temperatures to cover it from air and moisture, as indicated in Fig.
Page 191 - ... be adopted, almost regardless of expense, providing that the advantages gained are in any way commensurate with the cost. France has long appreciated this ; and it is to her that the world owes the Fresnel lens and many improved lamps burning successively whale, vegetable, and mineral oils. She has finally led the way, as usual, in the use of the electric light, which has been definitely adopted for the lighting of her coasts, after many expensive and conclusive experiments ; and, when the plan...
Page 103 - The coils are wound with wire of large diameter to a total resistance of 8 to 10 units in about 2,000 windings. Electric currents possessing great heating power, but of small electro-motive force, are generated by this machine.
Page 81 - ... Voltaic arc is peculiarly well adapted for use with such apparatus as it approaches most nearly the character of a luminous point. The lamp used is exceedingly simple and needs but little description in addition to the plates. It will be noticed that the carbons are inclined. This is because where a continuous current is used, the maximum intensity of the light is not in a plane perpendicular to the line of the carbons, but in one about 30° below. A small mirror, or sometimes a carbon plate...
Page 179 - The principle of action of the instruments employed depends upon the fact that the weight of metal deposited per unit of time in an electro-plating bath by electrolysis is proportioned to the quantity of electricity passing through it in the same period, or in other words, to the strength of the current ; and as the amount of this electro-deposition is equal at all points of a circuit, it follows that, by placing an electrolytic cell in any part of a circuit, the amount of electricity transmitted...