The electric motors

In parallel, an American scientist, Joseph Henry, came up with similar results. In 1831 he discovered self-induction and designed the first operable electric motor supplied with direct current from a battery. Henry devoted his experiments to a large extent to electromagnets. First, he constructed sets of electromagnets capable of lifting heavier and heavier weights and then took interest in their remote use.

 

In 1830 he linked a battery to one end of a pair of 1030 ft (314 m) long wires, and a signalling device (an electromagnet which caused a bell to strike) to the other end – when the current was switched on at one place it stirred an effect in another, completely distant place. In Henry’s own words: “This was the first discovery of the fact that a galvanic current could be transmitted a great distance with so little a diminution of force as to produce mechanical effects, and of the means by which the transmission could be accomplished. I saw that the electric telegraph was now practicable. I had not in mind any particular form of telegraph, but referred only to the general fact that it was now demonstrated that a galvanic current could be transmitted to great distances, with sufficient power to produce mechanical effects adequate to the desired object”.

 

The practical application of the concept of an electrical telegraph formulated by Henry was the work of many scientists. In 1833, Carl Friedrich Gauss and Wilhelm Weber built the first electrical telegraph in Germany. The first commercial telegraphic system for transmitting information was created by: Sir William Fothergill Cooke and Charles Wheatstone in 1837. Originally, it was used as an alarm system and in 1839 it was put into operation on the Great Western Railway line between Paddington and West Dayton – on a 21 km long section. The receiver comprised five needles moving across a board with letters of the alphabet. It did not support punctuation marks and did not distinguish between upper and lower case letters. Today, we tend to regard Samuel Morse as the “father” of telegraphy. In 1837, together with Alfred Veil, he developed an electrical telegraph capable of transmitting over long distances. Vail – Morse’s assistant – developed a special system of characters comprising sets of short and long pulses (so-called dots and dashes) corresponding to letters and digits. Six years later, US Congress assigned 30 thousand dollars for an experimental telegraph line between Baltimore and Washington and on 24 May 1844 Morse conducted the first public demonstration of his system. An excerpt from the Book of Numbers (23:23) – “What hath God wrought” was sent from the Supreme Court Chamber in Washington to the Baltimore & Oregon Railroad building in Baltimore. Over the next two decades, Morse’s telegraph system developed rapidly, thanks mainly to its simplicity and Alfred Vail’s improvements in electromagnets. Probably the most important and spectacular event in the history of the electrical telegraph was the 1866 launch of a transatlantic link between Valentia, an island off the western coast of Ireland and Newfoundland in the east of America. This was a groundbreaking event taking into account that previously it had taken about 10 days for a letter to reach America from Europe by sea provided the weather was good while it took only a few minutes to send and receive a telegram!

 

 

In the subsequent decades the most talented engineers and scientists continuously worked on improving the functioning of the telegraph. It often happened that they came up with new inventions. That was the case with Edison’s phonograph in 1877 as well as the telephone, a much more universal invention patented simultaneously by Alexander Graham Bell and Elisha Gray in 1870.

 

As often happens, a prototype of the telephone appeared much earlier. In 1857, Antonio Meucci, an Italian immigrant who had settled in New York seven years earlier, constructed a device that enabled communication between the cellar and the first storey of his house. Later, when his wife was bedridden due to severe arthritis, he also established a fixed line connecting the bedroom on the first floor with his laboratory. Unfortunately, he did not patent his invention. According to some, he did not have funds to do that, while according to others he did not speak English well enough to complete the bureaucratic procedures of the patent office. Both explanations seem a little exaggerated given that from 1859 until 1883 he was granted patents for fourteen other inventions. Meucci may well have underestimated the significance and development potential of the device he designed out of the necessity of the moment.

 

Returning to the subject of induction and its practical application, an electric motor was first put into practical use by Moritz Herman Jacobi, who in 1834 used it to drive an eight-metre-long boat carrying 12 passengers on the Neva river. Three years later in the USA, a blacksmith from Vermont, Thomas Davenport, patented his own model of an electric motor successfully used in his workshop to drive a wood drilling machine and a turning lathe. Unfortunately, due to a number of factors, and above all due to the lack of adequate sources of power supply (a motor connected to batteries could not compete with steam engines), Davenport’s invention was a commercial failure. The inventor himself, having failed to find investors in New York and elsewhere, returned to Vermont as a bankrupt and began working on a book describing the prospects of using his patent. He died in 1851, leaving the book unfinished.

 

Many scientists worked on electricity generators initiated by Faraday. In 1831 a Frenchman, Hippolyte Pixii, demonstrated a generator equipped with permanent magnets. Twenty years later, Floris Nollet patented and launched a serial production of an improved model of the above-mentioned generator supplying current up to 50 V. It was used in electroplating for making metallic coatings on various materials – thus, industrial use of electrical energy became a fact. In 1845, Charles Wheatstone, an author of many inventions, replaced permanent magnets in a current generator with electromagnets. Over the following 21 years he worked (among other reasons) to improve this solution, and finally on 4 February 1867 he reported the results of his studies to the Royal Society. By coincidence, ten days before, a similar dossier was sent to London by Ernst Werner von Siemens and both inventions – developed independently of each other – were announced to the public on the same day. In subsequent years, as the use of current became more and more common and as the requirement for this type of energy grew, current generators were regularly improved.

 


In 1879, at the Great Industrial Exhibition in Berlin, von Siemens presented an electric railway carrying passengers along a 300-metre-long circular track. The locomotive was supplied with power from a third rail placed between the running rails and it pulled three carriages. The first regular electric tramway line opened on 16 May 1881 in the present Berlin district of Gross Lichterfelde. Power was supplied to carriages via running rails placed on wooden sleepers. In the mid-1880s, in the USA and Germany a system was implemented where underground slotted conduits contained additional rails supplying power to the carriages. In the United States the conduits were usually located between or beside the running rails, while in Germany the preferred option was to lay them underneath the running rails. The power railed along which current collectors travelled were laid in the conduits. This solution was used for the first time in Cleveland (USA) in 1884, then in Budapest, and later in Berlin, Dresden, Vienna, London and Brussels. Around 1895, experiments were carried out with storage batteries but they proved too expensive to use.

 

A groundbreaking solution to the problem of supplying tram cars with power was the invention by Frank J. Sprague who in 1887 used wheels attached to the end of trolley poles spring-loaded to keep them in contact with the wires. Over the next few years, electric trams with an overhead line became widely used, first in American and after 1891 in European cities. At around the same time sliding current collectors were used on the tramway line in Gross Lichterfelde. They later evolved into the present-day pantographs.

 

 

The twentieth century automotive industry was dominated by internal combustion engines but by the time they achieved the parameters that ensured their supremacy, many speed and distance records had been set by vehicles propelled by electric motors. A watershed event was the breaking of the symbolic 100 km/h barrier by Camille Jenatzy, a Belgian who reached the maximum speed of 105.88 km/h in his futuristic vehicle bearing the meaningful name La Jamais Contente (Never Satisfied) on 29 April 1899. In the early 1900s electric vehicles had practically no rivals: they were free from vibration problems, and did not emit any stench or noise. They were very popular among wealthy buyers, in particular in cities. They were advertised as particularly suitable for women – with regard to the fact that were easy to start (the arduous turning of the starting crank was not required) and simple to drive (no need to change gears). The concept of electric cars did not die with the market success of internal combustion motor vehicles and new electric models appeared throughout the twentieth century. However, due to the limited battery capacity and relatively long charging time compared to filling a fuel tank, they tended to be regarded as experiments rather than cars for the masses. At the beginning of the 21st century we are returning to these concepts: on the tide of popularity of environment-friendly solutions, electric cars are back in fashion.