To the end of a sprit is attached an insulator of some kind, which may be a simple ebonite rod, or sometimes a more elaborate arrangement of oil insulators, and to the lower end of this insulator is attached the aerial wire.
These coils are, however, destitute of any iron core, and they generally consist of coils of wire wound on a fibre, wooden or ebonite frame, and must be immersed in a vat of oil to preserve the necessary insulation.
The details of the receiving arrangement are as follows:--The coherer tube consists of an ebonite tube containing hard steel particles of a uniform size, placed in the adjustable space between two polished steel electrodes.
At the farther extremity is an ebonite or boxwood collar ending in a rather wider metal ring.
Farther, it will be found that the rubber with which the ebonite or the glass rod have been excited has also acquired electrical properties, attracting the pith-ball, previously repelled by the rod.
This proves that the electrical condition of the excited ebonite and of the excited glass must be different; for had it been the same, the two balls would have repelled one another.
The apparatus has the form of a rod of a length that may be varied at will, according to the height of the burner to be lighted, and which terminates at its lower part in an ebonite handle about 4 centimeters in width by 20 in length (Fig.
Now the wires must not touch each other anywhere, but must be completely separated by the ebonite or sealing-wax.
If you cannot get ebonite easily you can use a small piece of sealing-wax in the same way; by heating the wires you can sink them into the wax and so make a neater join.
Now get a minute piece of ebonite of the same length, and, putting one hook on one side and one on the other, bind the whole together with silk.
The quartz rod which has been rubbed with silk has the same property of attracting light bodies which the ebonite and sealing-wax rod has, but it repels another rubbed quartz rod and attracts a rubbed ebonite or sealing-wax rod.
It will attract light pieces of paper or pith that are brought near to it, it will repel a similar rubbed piece of sealing-wax or ebonite and will attract a rod of quartz which has been rubbed with silk.
The ebonite is said to be negatively electrified and the quartz positively electrified.
When a stick of sealing-wax or ebonite is rubbed with flannel it becomes possessed of certain properties which it did not have before.
Electricity can be produced upon glass and ebonite because they do not carry or conduct it away.
The ebonite sheet E S is used with a flannel cloth to generate the electricity.
It can be shown that the electrification produced on all bodies by friction is not the same; for example, that generated with glass and silk is not the same as that made with ebonite and flannel.
It has been agreed to call that produced by glass and silk positive, and that by ebonite and flannel negative.
Resting in a central cavity of an ebonite seating is a carbon block, C, with a face moulded into a number of pyramidal projections, P P.
We will content ourselves with saying that the wax cylinder of the phonograph, or the ebonite disc of the gramophone, is generally rotated by clockwork concealed in the body of the machine.
From it as many as 1,000 copies may be made on ebonite plates by combined pressure and heating.
In a central hole of an ebonite casing is fixed a permanent magnet, M.
The movable or induced cylinder, B, of ebonite is provided with six equidistant and insulated thin sheets of tin of a width nearly equal to the interval which separates them.
A is an ebonite cylinder containing the entire machine, and closed above by a cap of the same substance upon which is screwed the lighting rod.
The index of refraction of ebonite was found by Profs.
Then recent experiments on the refractive power of ebonite were detailed--the rough results tending to give greater weight to Clerk-Maxwell's electro-magnetic theory of light.
This device, as shown in the accompanying illustration, is a glass cylinder fixed on an ebonite base, and closed at the top by an ebonite cap.
Opposite to this flat disk there is a brass strip secured to the ebonite cap.
As a rule two cells are put up in ebonite or celluloid boxes and joined in series so as to give a 4-volt battery, the pressure for which sparking coils are generally designed.
To prevent the active material from being shaken out of the grids, corrugated and perforated ebonite separators are placed between the plates.
If now a glass rod be electrified by friction with silk, it will be found that it attracts the suspended electrified ebonite rod.
To use the electrophorus, the ebonite is given a negative charge by striking it with fur or flannel.
Theoretically speaking, this process may be repeated continuously without affecting the original charge on the ebonite plate, but in practice the ebonite has to be re-excited from time to time on account of the loss of charge by leakage.
If a pair of ebonite rods be electrified by friction with flannel, then by suspending the one rod and presenting the other to it, it is easily demonstrated that a mutual mechanical force of repulsion exists between them.
This machine consists of two circular plates of glass or ebonite carrying equal even numbers of tinfoil sectors symmetrically placed on their outer surfaces.
Since the eboniteis an insulator, no general neutralization of the positive induced charge on the lower side of the metal disc can take place.
The charge produced on glass by friction with silk is called positive; that produced on ebonite by friction with flannel is called negative.
Many modifications have been patented by Hermite, that of 1895 specifying the use of platinum gauze anodes, held in ebonite or other frames.
On a rotating glass or ebonite disk were placed carriers of tin-foil or metal buttons against which neutralizing brushes touched.
If a parallel beam of radiation is required, a cylindrical lens of ebonite or sulphur is mounted in a tube fitting on to the radiator tube and stopped by a guide when the spark is at the principal focal line of the lens.
In front of them a disk of ebonite or glass, having carriers of metal fixed to its edge, was rotated by a winch.
Again he examined the connections running into the big, heavy tapping-key, and then, grasping the ebonite knob of the latter, he ticked out dots and dashes in a manner which showed him to be an expert telegraphist.
The whole is covered with a sheet of ebonite connected with the zinc and the two carbon plates in such a way that when the pile is not in operation the whole can be lifted from the liquid.
The insulating ebonite tube for such a coil should not be less than 1/4 in.
Over the primary circuit is placed another thick ebonite tube, the thickness of the walls of which is proportional to the spark-producing power of the secondary circuit.
Touch the tray with the finger for an instant, and lift up the ebonite without letting the hand touch the tray a second time.
Rub the sheet of ebonite with flannel, lay it face downwards on one tray, touch that tray with the finger for a moment and lift up the ebonite sheet, rub it again, and lay it face downwards on the second tray and leave it there.
Again, if, whilst holding the electrified ebonite over the tray, we touch the latter for a moment and then withdraw the ebonite sheet, the tray will be found to be positively electrified.
Let one tray be insulated as before, and the electrified sheet of ebonite held over it, but not allowed to touch the tray.
Charge positively a brass ball held on anebonite stem, and introduce it, without touching, into the canister.
If whilst holding the ebonite sheet over the tray the latter is also touched with an insulated brass ball, then this ball when removed and tested with the electroscope will be found to be negatively electrified.
If the ebonite is withdrawn without touching the tray, the latter will be found to be unelectrified.
Rub the sheet of ebonite vigorously with warm flannel and lay it rubbed side downwards on the top of the tray.
The last goes to earth when the tray is touched, and the first remains when the tray is insulated and the ebonite withdrawn.
The electrified eboniteis said to act by "electrostatic induction" on the tray, and creates on it two induced charges, one of positive and the other of negative electricity.
I may mention as a curious thing that these ravenous animals, that devoured everything they came across, even to the ebonite points of our ski-sticks, never made any attempt to break into the provision cases.
A strong smell of burning gutta-percha and ebonite greeted Peter as he gained the vicinity of the wireless-cabin.
In operation the contact breaker keeps the circuit closed during all of each revolution, except the brief interval in which the brushes pass over the ebonite segment.
The contact breaker consists of a commutator having an ebonite or insulating segment and two brushes.
The production of spark produced no effect, but the removal of the ebonite screen was at once followed by the characteristic response.
In order to show that the induced variation is due to the action of light and not to any other disturbance, I interposed a sheet of ebonite between the spark-gap and the plant.
The disk, P, being metallic and connected with one of the poles, there was placed upon it a thin ebonite plate of the same dimensions as the photographic one, and then the latter with the sensitized pellicle upward.
Then the photographic plate was entirely covered with a thin ebonite plate, above which there was a second one supported by small wedges, so as to allow air to circulate between them.
His apparatus, which contains no photographic objective, consists of an oblong case, ABCD, made of red glass and resting upon an ebonite table supported by one leg (Fig.
The leaves will diverge, even though the charged ebonite rod does not approach to within a foot of the electroscope.
The winding is usually covered and the ends capped with ebonite heads so that the core wires are not exposed.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "ebonite" in a variety of sentences. We hope that you will now be able to make sentences using this word.
