Induction Coils were invented by Michael Faraday (1791-1867) in 1831. They were used for medical complaints such as skin disorders and to power X ray machines. Marconi used one for his transmitter system for the first transatlantic transmission from Poldhu in Cornwall. They work by two coils, one with a smaller number of turns but of greater size of wire, surrounded by another of much greater turns but of smaller diameter wire, inside the centre winding is a core of iron at the end of which is a piece of metal, attached to a make and break contact which interrupts the supply to the centre winding, exactly as in an electric bell. The result is a transfer of power from the centre winding to the outer, with a proportional change in voltage to the number of turns, i.e from a small voltage you can create a very high voltage, but at much lower current.

Extract from ''The Lancet'' Dated January 16th 1892. Dr Edward Gans of Carlsbad has recently called the attention of the profession at Berlin to a simple instrument for the quantitive estimation of sugar in the urine, which is particularly adapted to the e wants of the general practitioner, on account of its accuracy and ease of manipulation. It consists of a U-shaped glass tube about six inches high, the longer leg of which is graduated as the annexed sketch shows, the shorter leg terminating in a glass bulb, on the extremity of which fits a glass stopper. The sides of the bulb of the stopper are pierced in corresponding diameters by two fine holes, so that the exit of air can be prevented by a slight turn of the latter. To use the instrument, mix in the flask 10cc. of the urine to be examined with 90cc of clean water, and shake up with a piece of yeast the size of a coffee bean until there is no longer fragments of the yeast floating about in the vessel, then pour 10cc of this mixture into the bulb and adjust the stopper so that the holes in the bulb and stopper coincide. Now tilt the hole to the left so that the level of the fluid in the tube corresponds with the zero on the scale, and by a slight turn of the stopper shut of communication with the atmosphere. Leave the instrument in an ordinary room temperature (about 65 deg F) for eighteen to twenty four hours, and fermentation going on, the liquid in the tube will rise from the point 0 in proportion to the amount of sugar in the urine. The instrument is so graduated that the points on the scale correspond to the percentage of sugar, so that if the tube rises to 2.5 the percentage of sugar is 2.5. After repeated experiments, Dr Gans found that the accuracy it almost equalled the method of polarisation, while in cases of the simultaneous presence of sugar and albumen in the urine it could be used when the polarimeter could not. (sic)

Also called a Gaussmeter, after Carl Friedrich Gauss in 1833. It measures the direction and strength of magnetic fields in the vicinity of other affecting objects. The earth's magnetic field (the Magnetosphere) varies due to influences of rocks and ores in the ground or the interaction between particles from the sun affecting the Magnetosphere. This is an early instrument for measuring these effects. It could be mounted on a long rod and slid along taking readings at precise intervals.

It has been said that this transmitter was used to ring the Division Bell in the Houses of Parliament and that the No 2 and 3 units were destroyed by a bomb in the Second World War; this however is unit No 2 and is alive and well.
When a plunger is pushed on the top of the unit the gears are turned thus winding up a weight hanging below. The weight starts to fall turning the mechanism. At the end of the gear line is an air type governor which controls the speed of fall; also connected is a rocker controlling two contacts which change alternately; these contacts are wired to terminals on the side of the unit.

Patents 16799 15th July 1914 and 24056 15th Dec 1914 accredited this item to Alexander William Sharman, holder of 40 other electrical and scientific patents. A transformer like search probe for locating breaks in metal pipes and cables which would be connected to the oscillator output red lead while the negative lead is connected to a metal stake which is driven into the ground to provide a return circuit. Headphones can be connected to the search probe or to the accessory search coil.

The National Grid was introduced in 1926. Power Stations such as Battersea, built in 1933, were to supply a grid of constant power to the entire nation. However building the plants and installing the power lines took nearly ten years. Some homes up to the Second World War were still using gas or limited electricity from local private companies, some supplying Direct Current of 110 volts. Early wireless's would be battery only, and DC was more convenient. This equipment was driven by an escapement which was wound up by the supply electrically, this drove the dials, their movement was controlled by two pendulums moving over the coils carrying the supply current, the more current drawn the faster the pendulums would swing, in a circular movement above the coils, this in turn moved the dials . No current at all, no movement.

Removed from The Whippendell Electric Works in Watford. Driven by a long case clock (not shown), and used to ring bells for tea breaks, clocking on and off times etc. In use during the second World War, and was installed long before that.

Wimshurst built these machines between 1880 and 1883. The two disks rotate in opposite directions when the handle is turned. Strips of foil on the disks are rubbed with two wire brushes, static is picked up by prongs positioned close to the disks and stored in two jars ( Leydn Jars ), When the charge is sufficient a large spark discharges the stored energy across a gap by two brass rods. This unit was used in schools and colleges up to the early 1980's and this unit is not antique, although they are now seldom seen, used as a training aid in a subject that is no longer considered important in a world of computers.

Able to punch cards or tape using 5 bit code (tape has five readable holes per character). Uses include fast transmission of telegraphy messages, paymaster data storage, or control of automatic equipment in a factory.

Wire recorders were invented in Denmark by Valdimar Poulson for an answering machine in 1898 called a Telegraphone, but was not developed for any other practical purpose at the time. Ten years later a company in America made a successful dictation machine. Although this machine carries the trade name Agaphone, this unit was certainly made by another company and was quickly made obsolete by magnetic tape machines.

The comptometer was invented by Dor Eugen Felt in the 1880's in America. Model L.C. 912/SF/6069. These units were leased in large numbers by companies such as Sumloc Comptometer, until electronic adding machines replaced them. The machines worked only by addition, other functions were completed by progressive use of the keys. Ladies often complained that the long strokes of pushing down the keys broke their finger nails.