ELECTROMAGNETISM

The traditional induction coil capable of producing a spark with an input of 6 - 12v DC and is therefore ideal for use with vacuum tubes, eudiometers etc. A fully adjustable vibration system is incorporated with spark suppression capacitors in the base. A pair of pointer electrodes is supplied with the instrument, the pointer electrode having an insulating handle for spark gap adjustment. Low v..

18th C. reproduction compass with brass lid protects the glass cover. This is after all an early travelers' compass. Lodestones were used by seafarers to keep magnets in good shape. Can you think of a better gift for a world traveler or antique lover? Ø 2.1 x 7.8cm, Ø 0.80 x 3.1" ..

The integrator is in reality a fluxmeter, which may be defined as a moving coil galvanometer specially designed for the measurement of magnetic fields, its deflections being determined solely by the total quantity of electricity discharged through the moving coil and being practically independent of the rate at which the discharge takes place. The special design of the integrator is such that i..

We are accustomed to the word galvanometer, which indicates the strength of an electric current. The Galvanoscope is an earlier instrument, which shows the presence of the current and gives only a rough indication of its magnitude    The basic galvanoscope has only a single turn of wire to set up the magnetic field which turns the magnetic needle. It can be made more sensitive by ..

A mirror galvanometer is a mechanical meter that senses electric current, except that instead of moving a needle, it moves a mirror. The mirror reflects a beam of light, which projects onto a meter, and acts as a long, weightless, massless pointer. In 1826, Johann Christian Poggendorff developed the mirror galvanometer for detecting electric currents. The apparatus is also known as a spot galva..

A tangent galvanometer is an early measuring instrument used for the measurement of electric current. It works by using a compass needle to compare a magnetic field generated by the unknown current to the magnetic field of the Earth. It gets its name from its operating principle, the tangent law of magnetism, which states that the tangent of the..

*Note that, while the images show the paper inside the glass frame as slighty pinkish, it is actually white. A deflection magnetometer measures the field lines of a magnet or magnets placed near to it by the amount of deflection caused by the bar magnet. This particular example is in good condition with some minor scuffs and scratches which are pictured. One such scratch is in a straigh..

A deflection magnetometer measures the field lines of a magnet or magnets placed near to it by the amount of deflection caused by the bar magnet. This magnetometer has a magnetometer box and two stems on which magnets can be placed and their distances from the centre measured. It has a glass window which is fixed in position. The paper on the inside is slightly warped but does not interfere..

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Unbranded tangent galvanometer, wood construction base & frame. Nice condition except for crack in coil former on one side, near bottom (not very big), and small chip out of wood case of compass, on top edge. Compass scale marked in degrees, 0-90 in 4 quadrants. Coil turns 3, 12 & 50. Detailled specifications e.g.thicknesses of the copper wire, mean diameter etc written on underside in ..

From the Philip Harris catalogue, 50th ed., 1950: "6779  GALVANOMETER, REFLECTING, MOVING COIL, APERIODIC orBALLISTIC. This galvanometwer comprises a moving coil system with a 1 cm. diameter concave mirror, suspended between the poles of a powerful permanent magnet by means of a phosphor bronze strip attached to an adjustable torsion head. Arrestment is obtained by depression of t..

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