Summary

Thomas Severi (1650-1715) was an English mechanic and inventor. One of the creators of the first thermal (steam) engine.

He was born at Shilston, near Modbury, Devonshire, supposedly in 1650.

The manager of one of the mines in Cornwall.

F.R.S. (Fellow of the Royal Society) - Member of the Royal Society (English Academy of Sciences). He died in May 1715 in London. On July 2, 1698 Severi patented the first steam engine, "a new invention for raising water for all kinds of mills by the motive power of fire, will have great use and advantages." He showed it to the Royal Society of London on June 14, 1699. The patent contained no illustration or even a description, but in 1702 Severi described the machine in his book The Miner's Friend, or the Engine for Raising Water by Fire, in which he claimed that it could pump water out of mines.

The Severi machine was a steam pump, not an engine: it did not have a cylinder with a piston that would drive anything as it moved. The most important thing about this device was that the steam to run the pump was generated in a separate boiler. It went like this. Steam was produced in the boiler, which was continuously heated. By opening a tap on a pipe, steam could be drawn into the pumping tank. There were two pipes that departed from it: one (suction pipe) went down into the shaft, the other (discharge pipe) went into the waste chute.

When steam was introduced into the tank, it began to push the water in the tank through the discharge pipe into the drain. The main disadvantage of the design that reduced its efficiency was that the steam entering the tank, came into contact with cold water from the mine (<100°C) and by the principle of the cold wall instantly condensing, heating the mine water, and not working until the surface layer is heated to 100 ° C, the device would have been improved if the separating heat insulating circle (say wooden), quickly heated by steam regardless of the temperature of the ejected water floated on the water surface. Thanks to such a solution, the described disadvantage was absent in D.Papen's machine, but it lacked a highly efficient steam condensation cycle. Then steam supply was stopped and cold water was injected into the tank through a special tube. Steam condensed, turning into water, and occupied a small volume, i.e. a reduced pressure was formed in the tank. The mine water was displaced by atmospheric pressure, directed through the suction pipe to the "empty" tank. Valves were installed on the suction and discharge pipes, letting water only from the shaft to the tank and from the tank to the drain, in the opposite direction they did not let water pass.

Severi was rather cautious about how powerful his pump was and was the first to use the term "horsepower". The Severi pump had serious shortcomings: it was low-powered, ate a lot of fuel during operation, and worked intermittently - water was pumped out in separate portions. It could not be used as a universal engine to drive various machines and mechanisms, because they mostly work continuously. Nevertheless, Severi's installation helped inventors to perceive the simple idea that steam from a separate boiler should be used in steam machines.

On July 2, 1698, he received the world's first royal patent for "a new invention for raising water and creating motion in any factory by means of the motive power of fire, which will have great use and advantage for draining mines, supplying cities with water, and for operating any factories in the absence of water streams or constantly blowing winds; for a term of 14 years; under ordinary conditions," in other words for a steam pump, which he himself called "fire engine" - fire engine.

There is reason to believe that in 1699 there was a presentation of the invention (working model) to the reigning King of Great Britain William III of Orange. These demonstrations yielded definite positive results. Initially the patent protected Severi's invention for a period of 14 years, but after the demonstrations by a special Act of Parliament called the "Fire Engine Act" the patent was extended for 21 years - up to 1733.

The author of A Miner's Friend, or, An Engine to Raise Water by Fire, Pater Noster Row, 1702, which describes the construction and operation of the "fire engine," with the second part in the spirit of an "FAQ," as the book's author answers questions from an imaginary customer. The book is signed Capt. Thomas Savery.

As a consequence, one often sees (even in university literature) that Captain Severi was supposedly a military engineer.

"Томас Сэвери ок. 1650-1715, английский инженер. Он стал военным инженером, дослужившись до звания капитана к 1702 году". (Колумбийская энциклопедия, шестое издание.)

"Thomas Severi, circa 1650-1715, an English engineer. He was a military engineer who attained the rank of captain in 1702." (Columbia Encyclopedia, Sixth Edition, Columbia University, New York, USA.)

"Savery, Thomas (c. 1650-1715). Savery was a military engineer who attained the rank of trench master by 1696, and acquired the title of 'Captain'."

"Severy Thomas (circa 1650-1715). Severi was a military engineer who attained the rank of trench master (perhaps "trench master" is better translated as "commander of sappers"?) in 1696 and achieved the rank of Captain."

The accounts of Captain Severi's military service are greatly exaggerated. He was one of the miners' captains.

MINE CAPTAIN. Usually dressed in a white work coat. It was the manager who ran the field on a day-to-day basis. In the larger mines there were several Captains, each in charge of a particular area and a "Grass Captain" who supervised the workers employed on the surface.

Presumably the very first "fire engine" Thomas Severi installed at the Wheal Vor mine on the south coast of Cornwall, near the village of Carleen, located about 2 miles northwest of Helston.

In 1717-18 the "fire engine" by order of Tsar Peter I was installed in St. Petersburg to supply water to about 50 fountains of the Summer Garden. It was none other than John Theophilus Desaguliers, a Frenchman by birth, who became a priest of rather high rank in England and the head of the first English Masonic lodge, who supervised the manufacturing and installation. Here is how Desagoulier himself writes about it:

"Beginning in 1717 or 1718, I built seven improved fire engines. The first was for the late Tsar Peter the Great, for his garden in St. Petersburg."

John Theophilus Desaguliers clearly disliked Thomas Severi, for in his "Experimental Philosophy," essentially the world's first course in general physics, he described the miner's captain's invention this way [J.T.Desaguliers. A Course of Experimental Philosophy Vol.2. - London, M.DCC.XLIV(1744)]:

Captain Severy, who had read the book of the Marquis of Worcester [meaning A Century of Inventions, printed in London in 1663], was the first to raise water by fire in practice and to suggest this method for draining mines. His engine is described in Harris's Dictionary, (see the word Engine), which, being compared with the description of the Marquis of Worcester, was simply borrowed from there. This fact Captain Severi denied, and, to better conceal it, bought up all the books of the Marquis of Wooster that he could find in Pater-Noster-Row and elsewhere, and burned them in the presence of a certain gentleman, a friend of his, who told me so.

Sources

1. Thomas Savery
2. Севери, Томас
3. ^ Elizabeth H. Oakes, A to Z of STS scientists, Facts on File Inc - 2002, ISBN 978-0-8160-4606-5 archive.org, p. 267
4. Thomas Savery // Store norske leksikon (бук.) — 1978. — ISSN 2464-1480
5. Thomas Savery // Gran Enciclopèdia Catalana (кат.) — Grup Enciclopèdia, 1968.
6. W.H.G. Armytage: A Social History of Engineering. Westview Press, 1976, ISBN 0-89158-508-7, S. 86.
7. J.A. Ewing: Encyclopaedia Britannica. 9. Auflage. Band 22. Charles Scribner's Sons, New York 1887, S. 473.
8. «Thomas Savery - Encyclopædia Britannica». Consultado em 7 de novembro de 2017