John Leslie | |
|---|---|
John Leslie | |
| Born | 10 April 1766 (1766-04-10) Largo, Fife |
| Died | 3 November 1832(1832-11-03) (aged 66) |
| Known for | Studies of heat Leslie cube |
| Awards | Rumford Medal(1804) |
| Scientific career | |
| Fields | Mathematics Physics |

Sir John Leslie,FRSEKH (10 April 1766 – 3 November 1832) was a Scottish mathematician andphysicist best remembered for his research into heat.[1]
Leslie gave the first modern account ofcapillary action in 1802[2] and froze water using anair-pump in 1810, the first artificial production ofice.
In 1804, he experimented withradiant heat using acubical vessel filled with boiling water. One side of the cube is composed of highly polished metal, two of dull metal (copper) and one side painted black. He showed that radiation was greatest from the black side and negligible from the polished side. The apparatus is known as aLeslie cube.
Leslie was born the son of Robert Leslie, a joiner and cabinetmaker, and his wife Anne Carstairs, inLargo inFife.[3] He received his early education there and atLeven. In his thirteenth year, encouraged by friends who had even then remarked his aptitude for mathematical and physical science, he entered theUniversity of St Andrews. On the completion of his course in 1784, he nominally studied divinity at theUniversity of Edinburgh but gained no further degrees.[4]
From 1788 to 1789 he spent rather more than a year as a private tutor in a Virginian family, and from 1791 until the close of 1792 he held a similar appointment atEtruria, Staffordshire, with the family ofJosiah Wedgwood, employing his spare time in experimental research and in preparing a translation ofBuffon'sNatural History of Birds, which was published in nine volumes in 1793, which brought him money.[4]


For the next twelve years (passed chiefly in London or at Largo, with an occasional visit to the continent of Europe) he continued his physical studies, which resulted in numerous papers contributed by him toNicholson'sPhilosophical Journal, and in the publication (1804) of theExperimental Inquiry into the Nature and Properties of Heat, a work which gained him theRumford Medal of theRoyal Society of London.[4]
In 1805, after having been rejected in several attempts to obtain a Chair at a Scottish university, Leslie was elected to succeedJohn Playfair in the chair of mathematics at Edinburgh, despite violent opposition on the part of a party who accused him of heresy.[5][4]
During his tenure of this chair he published two volumes ofA Course of Mathematics-the first, entitledElements of Geometry, Geometrical Analysis and Plane Trigonometry, in 1809, and the second,Geometry of Curve Lines, in 1813; the third volume, onDescriptive Geometry and the Theory of Solids was never completed. With reference to his invention (in 1810) of a process of artificialice-making, he published in 1813A Short Account of Experiments and Instruments depending on the relations of Air to Heat and Moisture; and in 1818 a paper by him,On certain impressions of cold transmitted from the higher atmosphere, with an instrument (theaethrioscope) adapted to measure them, appeared in theTransactions of the Royal Society of Edinburgh.[4]
In 1807 he became a member of theRoyal Society of Edinburgh.[6] His proposers wereJohn Playfair,Thomas Charles Hope andGeorge Dunbar.[7]
WhenJohn Playfair died in 1819, Leslie was promoted to the more congenial chair of natural philosophy, which he held until his death. He published a famous book about multiplication tableThe Philosophy of Arithmetic in 1820.[8] In 1823 he published, chiefly for the use of his class, the first volume of his never-completedElements of Natural Philosophy.[4]
Leslie's main contributions to physics were made by the help of the differential thermometer,[9] an instrument whose invention was contested with him byCount Rumford. By adapting to this instrument various ingenious devices, Leslie was able to employ it in a great variety of investigations, connected especially withphotometry,hygroscopy and the temperature of space. In 1820 he was elected a corresponding member of the Institute of France, the only distinction of the kind which he valued, and early in 1832 he was knighted.[4]
In his final years he is listed as living at 62 Queen Street, a large Georgian flat inEdinburgh's New Town.[10]
Leslie died oftyphus[11] in November 1832 (during the epidemic of that year) at Coates, a small property he had acquired near Largo inFife, at the age of 66.[4] He is buried inUpper Largo under a slab on the south side of the parish church.

Leslie was an atheist.[12]
John Leslie did not marry and had no children.
His nephew was the civil engineer,James Leslie, son of his brother, Alexander Leslie, an architect-builder in Largo. His great nephew (James's son) wasAlexander Leslie.