Tesla

Many of you will be aware that in the USA Elon Musk has been producing his Tesla electrically powered cars. Musk is also known for his company SpaceX, which has demonstrated a reusable rocket, intended for space travel. He is also involved in solar power and battery development. Many other manufacturers are also offering battery powered electric vehicles.
A few may ask why electric cars now? Because we can, and we need to cease burning fossil fuels, to save the planet.
Until recently most batteries were too bulky and heavy to power cars, as the usual battery was the lead acid type, originally called “accumulators”. The first publicly powered transport, electric railway, in this country was installed by Magnus Volk in 1883 along the Brighton sea front. This was not powered by batteries, but by a small power station at the trackside feeding electricity to the train via its rails.
I was privileged to be offered a ride on a prototype electric motor cycle in 1966 and was very impressed by its acceleration, compared with the old petrol driven machine I had previously owned. The electric motor cycle was limited in range by its battery then. Now battery developments make electric cars, and motor cycles, and even aircraft, to be possible. The new batteries are of the lithium-ion type using expensive imported material, but lithium is now being sourced in Cornwall. Lithium extraction may invigorate local industry there. Lithium is becoming one of the World’s most sought after commodities.
You may not know why Musk has called his electric car “Tesla”. Nikola Tesla was born in July 1856 in Smiljan, in Croatia. His parents were Serbs, who moved in the hope of a better life. At school Nikola was fascinated by the electrical and mechanical apparatus there. His father agreed that Nikola should attend the Polytechnic in Graz, Austria, to study engineering, but he left before finishing his course, due to illness. When his father died, Nikola enrolled at Prague University, but again left early and commenced working in Budapest on the new electric telegraph. This was at a time when great strides were being made in the knowledge of electrical apparatus. Tesla then moved to Paris, working for one of Edison’s telegraph companies.
Edison was an inventor of many electrical devices, including the phonograph, and was also excellent at self promotion, photographed at his headquarters in America, dressed as “The Wizard of Menlo Park”. At first Edison became a hero to Tesla. Edison had commenced electrical power distribution in New York for residents and businesses, using direct current, DC. Tesla moved to New York in 1884 to work for Edison there, but could not agree that the future was in direct current as he had been developing alternating current, AC, machines. He left Edison’s employment after six months, but he had learnt from Edison the value of being something of a showman to promote his inventions.
In 1887 Tesla patented two and three phase alternators and induction motors and in 1888 he and Ferrari independently produced rotating magnetic fields. These inventions were most important in the introduction of electrical machinery. Tesla appears to have influenced some backers and also senior electrical engineers, as he was able to lecture to the American Institution of Electrical Engineers (AIEE) in 1888 on “AC Motors and Transformers”, opened by William Anthony, Professor at Cornell University. Tesla went on to develop and patent a polyphase motor. As a result of the 1888 lecture he met George Westinghouse, who owned the Westinghouse Electrical Manufacturing Co. Westinghouse purchased Tesla’s patents for AC machines. As a result, Westinghouse made and installed Tesla induction motors in a new factory at East Pittsburgh. Tesla went on to work for Westinghouse, but left after a year, it appears that he found it difficult to work under the direction of others.
Edison was distributing DC electricity in New York, but Westinghouse then commenced with AC. Edison campaigned against the use of AC, saying it was liable to kill people, if distributed at high voltage. However Europe expanded the use of AC, and eventually across the globe, people began to disagree with Edison.
Maxwell and Hertz had both discovered electro-magnetic waves in 1888 and in 1890 Nikola Tesla invented what he called an “Oscillating Transformer”, which is commonly referred to as a Tesla Coil, or transformer.
I referred to my well thumbed copy of The Boy Electrician of 1944 for a description and illustrations of a small Tesla high-frequency coil, which detailed an outer cylindrical primary winding of eight turns of fairly large diameter copper wire, spaced apart. A secondary winding is described of thinner cotton insulated wire, wound closely on a three inch diameter cardboard tube, twelve inches long, probably about 750 turns. Hence a turns ratio of about 94 to one. The secondary winding is mounted concentrically within the primary winding. The secondary windings are terminated each to a brass rod, each topped by a brass ball. If a battery, capacitor and a spark gap are connected to the primary winding, sparks should appear if a hand is near a brass ball. In the dark a brush discharge is evident around the secondary terminations and sparks may jump to the hand, with no sensation. I have taken this description at length, as a Tesla Coil may now not be familiar to many.
Nikola Tesla made his coil much larger and energised it from a high frequency alternator of his design and demonstrated it to the American IEE at Columbia College in 1891, producing spark discharges. He also held discharge tubes in his hands, not connected to a supply, which glowed when near the apparatus. He also came to the UK and gave a similar demonstration to the British IEE at the Royal Institution in 1892. These demonstrations were spectacular, and they still are. The technical press gave graphic descriptions and the reputation of Tesla was greatly enhanced. In my opinion Tesla reached the peak of his achievements around this time.
It had been agreed that the power of the Niagara Falls should be used for electricity generation by the Westinghouse Company and this was a great success. Many people thought that Tesla must have been involved, whether he was or not. This notoriety seems to have “gone to his head”. Tesla said of Marconi, who was rapidly developing his wireless equipment, that ‘Signor Marconi’s experiments are interesting, but they are not novel’. What Tesla had forgotten was that most developments are built on the achievements of others, including his own.
In 1897 Tesla filed another patent for generating high frequency electricity, with one terminal earthed and the other at an elevation, to pass electricity into higher, rarefied atmosphere, where he suggested that current would be freely conducted. He had a laboratory erected in Colorado Springs with a large version of his Oscillating Transformer as a transmitter, with a primary winding of two turns of thick cable and a secondary of one hundred turns of smaller cable. The secondary had one end grounded and the other attached to a large copper ball on top of a mast. He described it as a conductor via the earth of unlimited power, for the human voice. Unfortunately in 1895 fire destroyed his laboratory.
Nikola Tesla began to “enjoy the high life”, living in top hotels and eating in the best restaurants where he rubbed shoulders with famous people. He was making more amazing prophecies of the results of his inventions, for example that he had received faint signals from space and he started to lose the support of some of his friends.
Tesla managed to obtain funding in exchange for a majority interest in his latest patents and was able to build an even larger laboratory at Wardenclyffe, 65 miles from New York. This was topped by a tower about 190 feet tall which apparently produced lightning flashes at night. He said that he expected to be able to distribute electrical power through the earth, or alternatively messages. No one else noticed other than the flashes from the tower. At this time Marconi was forging ahead with his installations. Unfortunately for Tesla, some of his creditors foreclosed and Wardenclyffe was taken from his hands by 1904. Tesla moved to a less expensive hotel in New York where he died in his sleep on 7 January 1943, aged 86.
His work, and that of his contemporaries lives on in modern advances. His ideas and those of Maxwell, Hertz and others may be seen now in contemporary battery charging by high frequency electro-magnetic waves of mobile phones and soon for vehicles in non plug in supplies, as well as those we already take for granted.
Nikola Tesla was honoured by the international scientific community in 1960 by using his name for the unit of magnetic flux density, “the Tesla”, symbol “T”, in SI Units. As the song goes ‘Ah Yes, I remember it well’.
In his lifetime Tesla produced over 90 US patents, 30 British and 25 in other countries, some duplicated, mainly electrical. Latterly probably they were almost duplicates. It was unfortunate that he ended up penniless after all his efforts, having sold many of his patents in order to invest in more experiments.
This article is largely based on a recent book Nikola Tesla and the Electrical Future by Iwan Rhys Morus, Professor of History at Aberystwyth University, with grateful thanks. I apologise for so much essential technical detail in this article.
Bridport History Society will appear again on Zoom on Tuesday 8th June at 2 for 2.30 pm when Carlos Guarita will answer “What is Photo Archaeology”. For details contact Jane on 01308 425710 or email jferentzi@aol.com.
Cecil Amor, Hon President, Bridport History Society.