James David Forbes (1809–1868) was a Scottish physicist and
glaciologist who worked extensively on the
conduction of heat and
seismology
Seismology (; from Ancient Greek σεισμός (''seismós'') meaning "earthquake" and -λογία (''-logía'') meaning "study of") is the scientific study of earthquakes and the propagation of elastic waves through the Earth or through other ...
. Forbes was a resident of
Edinburgh
Edinburgh ( ; gd, Dùn Èideann ) is the capital city of Scotland and one of its 32 Council areas of Scotland, council areas. Historically part of the county of Midlothian (interchangeably Edinburghshire before 1921), it is located in Lothian ...
for most of his life, educated at its
University
A university () is an institution of higher (or tertiary) education and research which awards academic degrees in several academic disciplines. Universities typically offer both undergraduate and postgraduate programs. In the United Stat ...
and a professor there from 1833 until he became principal of the
United College of St Andrews in 1859.
He invented an inverted pendulum
seismometer in 1842.
Life and work
Forbes was born on 20 April 1809 at 86
George Street in Edinburgh, the fourth son of Sir
William Forbes, 7th Baronet
There have been five Baronetcies created for people with the surname Forbes, four in the Baronetage of Nova Scotia and one in the Baronetage of the United Kingdom. The first holder of the Burn Baronetcy of Jessfield, created in the Baronetage of ...
, of
Monymusk and
Pitsligo
Pitsligo was a coastal parish in the historic county of Aberdeenshire, Scotland, containing the fishing villages of Rosehearty, Pittulie and Sandhaven, (1773–1828) and Williamina Belches of
Invermay
Invermay () is a diffuse settlement in Perth and Kinross, Scotland. It is situated approximately 2 km southeast of Forteviot on the Water of May, some 8 km southwest of Perth.
Before the mid 15th century, it was known as ''Innermeat ...
. His brothers were the advocate and agriculturalist Sir
John Stuart Hepburn Forbes
Sir John Stuart Hepburn Forbes, 8th Baronet, of Monymusk, of Fettercairn and Pitsligo, FRSE (1804–1866) was a Scottish baronet, landowner, advocate and agriculturalist. His name sometimes appears as Hepburn-Forbes.
Life
He was born in Dean ...
of Fettercairn and Pitsligo and the banker Charles Forbes.
He entered the
University of Edinburgh
The University of Edinburgh ( sco, University o Edinburgh, gd, Oilthigh Dhùn Èideann; abbreviated as ''Edin.'' in post-nominals) is a public research university based in Edinburgh, Scotland. Granted a royal charter by King James VI in 1 ...
in 1825, and soon afterwards began to contribute papers to the ''Edinburgh Philosophical Journal'' anonymously under the signature "Δ". At the age of nineteen he became a fellow of the
Royal Society of Edinburgh, and in 1832 he was elected to the
Royal Society of London
The Royal Society, formally The Royal Society of London for Improving Natural Knowledge, is a learned society and the United Kingdom's national academy of sciences. The society fulfils a number of roles: promoting science and its benefits, r ...
. At this time he maintained correspondence with Sir
David Brewster, who encouraged him to pursue an original research in science. A year later he was appointed professor of natural philosophy at the University of Edinburgh in succession to Sir
John Leslie, and during his tenure of that office, which he did not give up till 1860, he not only proved himself an active and efficient teacher, but also did much to improve the internal conditions of the university. In 1859 he was appointed successor to Brewster in the principalship of the United College of St Andrews, a position which he held until his death at Clifton in 1868.
As a scientific investigator he is best known for his researches on heat and on glaciers. Between 1836 and 1844 he published in the ''Trans. Roy. Soc. Ed.'' four series of "Researches on Heat," in the course of which he demonstrated that
tourmaline
Tourmaline ( ) is a crystalline Silicate mineral, silicate mineral group in which boron is compounded with elements such as aluminium, iron, magnesium, sodium, lithium, or potassium. Tourmaline is a gemstone and can be found in a wide variety o ...
would
polarise infrared
Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of Light, visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from ...
thermal radiation
Thermal radiation is electromagnetic radiation generated by the thermal motion of particles in matter. Thermal radiation is generated when heat from the movement of charges in the material (electrons and protons in common forms of matter) i ...
, by transmission through a bundle of thin mica plates inclined to the transmitted ray, and by reflection from the multiplied surfaces of a pile of
mica plates placed at the polarising angle, and also its
circular polarisation by two internal reflections in
rhombs of
rock salt. His work won him the
Rumford Medal of the Royal Society in 1838, and in 1843 he received its
Royal Medal for a paper on the "Transparency of the Atmosphere and the Laws of Extinction of the Sun's Rays passing through it."
In response to a series of earthquakes near
Comrie in
Scotland
Scotland (, ) is a country that is part of the United Kingdom. Covering the northern third of the island of Great Britain, mainland Scotland has a border with England to the southeast and is otherwise surrounded by the Atlantic Ocean to ...
in 1839, a committee was formed in the
United Kingdom
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and ...
in order to produce better detection methods for earthquakes. The outcome of this was the production of one of the first modern
seismometers by Forbes, first presented in a report by
David Milne-Home in 1842.
This seismometer was an inverted pendulum, which recorded the measurements of seismic activity through the use of a pencil placed on paper above the pendulum. The designs provided did not prove effective, according to Milne's reports.
In 1846 he began experiments on the temperature of the earth at different depths and in different soils near Edinburgh, which yielded determinations of the thermal conductivity of trap-tufa,
sandstone
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks.
Most sandstone is composed of quartz or feldspar (both silicat ...
and pure loose
sand
Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural class ...
. Towards the end of his life he was occupied with experimental inquiries into the laws of the conduction of heat in iron bars, and his last piece of work was to show that the thermal conductivity of iron diminishes with increase of temperature.
His attention was directed to the question of the flow of glaciers in 1840 when he met
Louis Agassiz at the Glasgow meeting of the British Association, and in subsequent years he made several visits to Switzerland, where he was particularly impressed by
Bernhard Studer's theories, and also to Norway for the purpose of obtaining accurate data. His observations led him to the view that a glacier is an imperfect fluid or a viscous body which is urged down slopes of a certain inclination by the mutual pressure of its parts, and involved him in some controversy with Tyndall and others both as to priority and to scientific principle. A notable defender of Forbes in this controversy was
John Ruskin
John Ruskin (8 February 1819 20 January 1900) was an English writer, philosopher, art critic and polymath of the Victorian era. He wrote on subjects as varied as geology, architecture, myth, ornithology, literature, education, botany and pol ...
, the two having first met by coincidence in 1844 during a study tour of the
Alps
The Alps () ; german: Alpen ; it, Alpi ; rm, Alps ; sl, Alpe . are the highest and most extensive mountain range system that lies entirely in Europe, stretching approximately across seven Alpine countries (from west to east): France, Sw ...
.
During these expeditions, he made many measurements of the
boiling point
The boiling point of a substance is the temperature at which the vapor pressure of a liquid equals the pressure surrounding the liquid and the liquid changes into a vapor.
The boiling point of a liquid varies depending upon the surrounding env ...
of water at various altitudes. This data set, published in 1857, is often known in statistics as ''Forbes's data'', its utility being that:
*It illustrates how a
curvilinear relationship between a
dependent and
independent variable can be transformed into a
linear model by knowledge of the
physical phenomenon
A phenomenon ( : phenomena) is an observable event. The term came into its modern philosophical usage through Immanuel Kant, who contrasted it with the noumenon, which ''cannot'' be directly observed. Kant was heavily influenced by Gottfrie ...
observed.
*It emphasises the importance of
residuals analysis in
linear regression as the residuals manifest an
outlier that is not apparent in a visual inspection of the raw data.
Forbes was also interested in geology, and published memoirs on the thermal springs of the
Pyrenees
The Pyrenees (; es, Pirineos ; french: Pyrénées ; ca, Pirineu ; eu, Pirinioak ; oc, Pirenèus ; an, Pirineus) is a mountain range straddling the border of France and Spain. It extends nearly from its union with the Cantabrian Mountains to ...
, on the extinct volcanoes of the Vivarais (
Ardèche), on the geology of the Cuchullin and Eildon hills, etc. In addition to about 150 scientific papers, he wrote ''Travels through the Alps of Savoy and Other Parts of the Pennine Chain, with Observations on the Phenomena of Glaciers'' (1843); ''Norway and its Glaciers'' (1853); ''Occasional Papers on the Theory of Glaciers'' (1859); ''A Tour of Mont Blanc and Monte Rosa'' (1855). He was also the author (1852) of the "Dissertation on the Progress of Mathematical and Physical Science," published in the eighth edition of the ''
Encyclopædia Britannica
The (Latin for "British Encyclopædia") is a general knowledge English-language encyclopaedia. It is published by Encyclopædia Britannica, Inc.; the company has existed since the 18th century, although it has changed ownership various t ...
''.
The
Forbes River and
Forbes Glaciers in New Zealand are named after him as is Aiguille Forbes between the
Glacier de Saleina and the Glacier du Tour in the
Mont Blanc massif
The Mont Blanc massif (french: Massif du Mont-Blanc; it, Massiccio del Monte Bianco) is a mountain range in the Alps, located mostly in France and Italy, but also straddling Switzerland at its northeastern end. It contains eleven major indep ...
.
James David Forbes was a devout Christian, as can be seen in the work "''Life and Letters of James David Forbes"'' (1873), a compilation of personal letters written by Forbes, co-authored by
John Campbell Shairp
John Campbell Shairp (30 July 1819 – 18 September 1885) was a Scottish critic and man of letters.
Life
He was born at Houstoun House, Linlithgowshire, the third son of Major Norman Shairp of Houstoun, and was educated at Edinburgh Acade ...
and Forbes's student
Peter Guthrie Tait.
He died on 31 December 1868 and is buried in
Dean Cemetery in
Edinburgh
Edinburgh ( ; gd, Dùn Èideann ) is the capital city of Scotland and one of its 32 Council areas of Scotland, council areas. Historically part of the county of Midlothian (interchangeably Edinburghshire before 1921), it is located in Lothian ...
. The grave is marked by a simple but large grey granite
Celtic cross and lies on the south side of the main path just west of the roundel. His wife, Alicia Wauchope (1824–1885), is buried with him. His cousins were
Scottish Episcopal Church
The Scottish Episcopal Church ( gd, Eaglais Easbaigeach na h-Alba; sco, Scots Episcopal(ian) Kirk) is the ecclesiastical province of the Anglican Communion in Scotland.
A continuation of the Church of Scotland as intended by King James VI, and ...
leaders
Alexander Penrose Forbes and
George Hay Forbes. His son was the scientist
George Forbes.
Selected publications
*
*
*
*
References
Further reading
*
*''Professor Forbes and his Biographers'', by
John Tyndall (1873)
External links
*
Pictures and texts of ''Travels through the Alps of Savoy and other parts of the Pennine Chain'' by James David Forbes can be found in the database VIATIMAGES
Papers of James David Forbes University of St Andrews.
{{DEFAULTSORT:Forbes, James David
1809 births
1868 deaths
Scientists from Edinburgh
Alumni of the University of Edinburgh
Academics of the University of Edinburgh
Principals of the University of St Andrews
Scottish mountain climbers
Scottish physicists
Scottish inventors
Fellows of the Royal Society of Edinburgh
Fellows of the Royal Society
British glaciologists
Royal Medal winners
19th-century Scottish people
Scottish geologists
Burials at the Dean Cemetery
British seismologists
Scottish Christians