Henry Kater
Encyclopedia
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...
physicist
Physicist
A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...
of German
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
descent.
Early life
He was born at BristolBristol
Bristol is a city, unitary authority area and ceremonial county in South West England, with an estimated population of 433,100 for the unitary authority in 2009, and a surrounding Larger Urban Zone with an estimated 1,070,000 residents in 2007...
. At first he intended to study law
Law
Law is a system of rules and guidelines which are enforced through social institutions to govern behavior, wherever possible. It shapes politics, economics and society in numerous ways and serves as a social mediator of relations between people. Contract law regulates everything from buying a bus...
; but he gave up the idea on his father's death in 1794. He entered the army, obtaining a commission in the 12th Regiment of Foot, then stationed in India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
, where he assisted William Lambton
William Lambton
Lieutenant-Colonel William Lambton, FRS was a British soldier, surveyor, and geographer.Lambton was the Superintendent of the Trigonometrical Survey of India, which he began in 1802. He died and is buried at Hinganghat in Wardha district of Maharashtra...
in the Great Trigonometric Survey
Great Trigonometric Survey
The Great Trigonometric Survey was a project of the Survey of India throughout most of the 19th century. It was piloted in its initial stages by William Lambton, and later by George Everest. Among the many accomplishments of the Survey were the demarcation of the British territories in India and...
. Failing health obliged him to return to England; and in 1808, then a lieutenant, he entered on a student career in the senior department of the Royal Military College at Sandhurst
Royal Military Academy Sandhurst
The Royal Military Academy Sandhurst , commonly known simply as Sandhurst, is a British Army officer initial training centre located in Sandhurst, Berkshire, England...
. Shortly afterwards he was promoted to the rank of captain. In 1814 he retired on half-pay, and devoted the remainder of his life to scientific research.
Scientist
His first major contribution to science was the comparison of the merits of the Cassegrainian and Gregorian telescopeGregorian telescope
The Gregorian telescope is a type of reflecting telescope designed by Scottish mathematician and astronomer James Gregory in the 17th century, and first built in 1673 by Robert Hooke...
s; Kater determined the latter to be an inferior design.
His most substantial work was the invention of Kater's pendulum
Kater's pendulum
A Kater's pendulum is a reversible freeswinging pendulum invented by British physicist and army captain Henry Kater in 1817 for use as a gravimeter instrument to measure the local acceleration of gravity. Its advantage is that, unlike previous pendulum gravimetry methods, the pendulum's centre of...
, enabling the strength of gravity to be determined, first at London
London
London is the capital city of :England and the :United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its...
and subsequently at various stations throughout the country. As the inventor of the floating collimator
Collimator
A collimator is a device that narrows a beam of particles or waves. To "narrow" can mean either to cause the directions of motion to become more aligned in a specific direction or to cause the spatial cross section of the beam to become smaller.- Optical collimators :In optics, a collimator may...
, Kater rendered a service to practical astronomy
Astronomy
Astronomy is a natural science that deals with the study of celestial objects and phenomena that originate outside the atmosphere of Earth...
. He also published memoirs on British standards of length and mass
Metrology
Metrology is the science of measurement. Metrology includes all theoretical and practical aspects of measurement. The word comes from Greek μέτρον , "measure" + "λόγος" , amongst others meaning "speech, oration, discourse, quote, study, calculation, reason"...
; and in 1832 he published an account of his work on verifying the Russian standards of length. For these services to Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
he received in 1814 the decoration of the order of St. Anne
Order of St. Anna
The Order of St. Anna ) is a Holstein and then Russian Imperial order of chivalry established by Karl Friedrich, Duke of Holstein-Gottorp on 14 February 1735, in honour of his wife Anna Petrovna, daughter of Peter the Great of Russia...
; and the same year he was elected a Fellow of the Royal Society. In 1826, he was elected a foreign member of the Royal Swedish Academy of Sciences
Royal Swedish Academy of Sciences
The Royal Swedish Academy of Sciences or Kungliga Vetenskapsakademien is one of the Royal Academies of Sweden. The Academy is an independent, non-governmental scientific organization which acts to promote the sciences, primarily the natural sciences and mathematics.The Academy was founded on 2...
.
He won the Copley Medal
Copley Medal
The Copley Medal is an award given by the Royal Society of London for "outstanding achievements in research in any branch of science, and alternates between the physical sciences and the biological sciences"...
in 1817 and the Gold Medal of the Royal Astronomical Society
Gold Medal of the Royal Astronomical Society
-History:In the early years, more than one medal was often awarded in a year, but by 1833 only one medal was being awarded per year. This caused a problem when Neptune was discovered in 1846, because many felt an award should jointly be made to John Couch Adams and Urbain Le Verrier...
in 1831.
He is considered as the inventor of the prismatic compass, patented a year later by Charles Schmalcalder.
He also studied compass needles, his Bakerian lecture
Bakerian Lecture
The Bakerian Lecture is a prize lecture of the Royal Society, a lecture on physical sciences.In 1775 Henry Baker left £100 for a spoken lecture by a Fellow on such part of natural history or experimental philosophy as the Society shall determine....
containing the results of many experiments. The treatise on "Mechanics" in Dionysius Lardner
Dionysius Lardner
Dionysius Lardner , was an Irish scientific writer who popularised science and technology, and edited the 133-volume Cabinet Cyclopedia.-Early life in Dublin:...
's Cabinet Cyclopedia was partly written by him; and his interest in more purely astronomical questions was shown by two communications to the Astronomical Society
Astronomical society
There are numerous groups devoted to promoting astronomy research and education. See, for example:* Amateur Astronomers Association Delhi * Amateur Astronomers Association of New York * Amateur Astronomers Association of Pittsburgh...
's Memoirs for 1831–1833 — one on an observation of Saturn
Saturn
Saturn is the sixth planet from the Sun and the second largest planet in the Solar System, after Jupiter. Saturn is named after the Roman god Saturn, equated to the Greek Cronus , the Babylonian Ninurta and the Hindu Shani. Saturn's astronomical symbol represents the Roman god's sickle.Saturn,...
's outer ring, the other on a method of determining longitude
Longitude
Longitude is a geographic coordinate that specifies the east-west position of a point on the Earth's surface. It is an angular measurement, usually expressed in degrees, minutes and seconds, and denoted by the Greek letter lambda ....
by means of lunar eclipse
Lunar eclipse
A lunar eclipse occurs when the Moon passes behind the Earth so that the Earth blocks the Sun's rays from striking the Moon. This can occur only when the Sun, Earth, and Moon are aligned exactly, or very closely so, with the Earth in the middle. Hence, a lunar eclipse can only occur the night of a...
s.