Thomas Melvill
Encyclopedia
Thomas Melvill (1726–1753) was a Scottish
natural philosopher
, who was active in the fields of spectroscopy
and astronomy
.
The son of Helen Whytt and the Rev Andrew Melville, minister of Monimail (d. 29 July 1736), Thomas was a student at Glasgow University. In 1749, with Alexander Wilson, his landlord and later the first professor of astronomy at Glasgow University, made the first recorded use of kites in meteorology. They measured air temperature at various levels above the ground simultaneously with a train of kites.
He most notably delivered a lecture entitled Observations on light and colours to the Medical Society of Edinburgh
in 1752, in which he described what has been seen as the first flame test
. In it he described how he had used a prism
to observe a flame coloured by various salts. He reported that a yellow line was always seen at the same place in the spectrum; this was derived from the sodium
which was present as an impurity in all his salts. Because of this, he is sometimes described as the father of flame emission spectroscopy, though he did not identify the source of the line, or propose his experiment as a method of analysis. He also proposed that light rays of different colours travelled at different speeds to explain the action of a prism, and suggested that this could be verified if the moons of Jupiter
appeared as slightly different colours at different stages of their orbit. An experiment by James Short failed to confirm his hypothesis. Melvill died in Geneva
in 1753, aged 27.
Scotland
Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...
natural philosopher
Natural philosophy
Natural philosophy or the philosophy of nature , is a term applied to the study of nature and the physical universe that was dominant before the development of modern science...
, who was active in the fields of spectroscopy
Spectroscopy
Spectroscopy is the study of the interaction between matter and radiated energy. Historically, spectroscopy originated through the study of visible light dispersed according to its wavelength, e.g., by a prism. Later the concept was expanded greatly to comprise any interaction with radiative...
and astronomy
Astronomy
Astronomy is a natural science that deals with the study of celestial objects and phenomena that originate outside the atmosphere of Earth...
.
The son of Helen Whytt and the Rev Andrew Melville, minister of Monimail (d. 29 July 1736), Thomas was a student at Glasgow University. In 1749, with Alexander Wilson, his landlord and later the first professor of astronomy at Glasgow University, made the first recorded use of kites in meteorology. They measured air temperature at various levels above the ground simultaneously with a train of kites.
He most notably delivered a lecture entitled Observations on light and colours to the Medical Society of Edinburgh
Royal Medical Society
The Royal Medical Society is the oldest medical society in the United Kingdom . Known originally as 'the Medical Society' when it was established in 1737, it was granted a Royal Charter in 1778...
in 1752, in which he described what has been seen as the first flame test
Flame test
A flame test is a procedure used in chemistry to detect the presence of certain metal ions, based on each element's characteristic emission spectrum. The color of flames in general also depends on temperature; see flame color....
. In it he described how he had used a prism
Dispersive prism
In optics, a dispersive prism is a type of optical prism, normally having the shape of a geometrical triangular prism. It is the most widely-known type of optical prism, although perhaps not the most common in actual use. Triangular prisms are used to disperse light, that is, to break light up into...
to observe a flame coloured by various salts. He reported that a yellow line was always seen at the same place in the spectrum; this was derived from the sodium
Sodium
Sodium is a chemical element with the symbol Na and atomic number 11. It is a soft, silvery-white, highly reactive metal and is a member of the alkali metals; its only stable isotope is 23Na. It is an abundant element that exists in numerous minerals, most commonly as sodium chloride...
which was present as an impurity in all his salts. Because of this, he is sometimes described as the father of flame emission spectroscopy, though he did not identify the source of the line, or propose his experiment as a method of analysis. He also proposed that light rays of different colours travelled at different speeds to explain the action of a prism, and suggested that this could be verified if the moons of Jupiter
Jupiter
Jupiter is the fifth planet from the Sun and the largest planet within the Solar System. It is a gas giant with mass one-thousandth that of the Sun but is two and a half times the mass of all the other planets in our Solar System combined. Jupiter is classified as a gas giant along with Saturn,...
appeared as slightly different colours at different stages of their orbit. An experiment by James Short failed to confirm his hypothesis. Melvill died in Geneva
Geneva
Geneva In the national languages of Switzerland the city is known as Genf , Ginevra and Genevra is the second-most-populous city in Switzerland and is the most populous city of Romandie, the French-speaking part of Switzerland...
in 1753, aged 27.