See also:

• HENRY
• HENRY (1129-1195)
• HENRY (c. 1108-1139)
• HENRY (c. 1174–1216)
• HENRY (Fr. Henri; Span. Enrique; Ger. Heinrich; Mid. H. Ger. Heinrich and Heimrich; O.H.G. Haimi- or Heimirih, i.e. " prince, or chief of the house," from O.H.G. heim, the Eng. home, and rih, Goth. reiks; compare Lat. rex " king "—" rich," therefore " mig
• HENRY, EDWARD LAMSON (1841– )
• HENRY, JAMES (1798-1876)
• HENRY, JOSEPH (1797-1878)
• HENRY, MATTHEW (1662-1714)
• HENRY, PATRICK (1736–1799)
• HENRY, PRINCE OF BATTENBERG (1858-1896)
• HENRY, ROBERT (1718-1790)
• HENRY, VICTOR (1850– )
• HENRY, WILLIAM (1795-1836)

HENRY See also:

• HENRY KATER (1777-1835)

KATER (1777-1835)  , See also:

• ENGLISH

English physicist of See also:

• GERMAN
• GERMAN, DUTCH AND SCANDINAVIAN

German descent, was See also:

• BORN, IGNAZ, EDLER VON (1742–1791)

born at See also:

• BRISTOL
• BRISTOL, EARLS AND MARQUESSES OF
• BRISTOL, GEORGE DIGBY, 2ND EARL OF1 (1612-1677)
• BRISTOL, JOHN DIGBY, 1ST EARL OF 6 (1580-1653)

Bristol on the 16th of See also:

• APRIL

April 1777 . At first he purposed to study See also:

• LAW
• LAW (0. Eng. lagu, M. Eng. lawe; from an old Teutonic root lag, " lie," what lies fixed or evenly; cf. Lat. lex, Fr. loi)
• LAW, JOHN (1671—1729)
• LAW, WILLIAM (1686-1761)

law; but this he abandoned on his See also:

• FATHER

father's See also:

• DEATH

death in 1794, and entered the See also:

• ARMY
• ARMY (from Fr. armee, Lat. armata)

army, obtaining a See also:

• COMMISSION (from Lat. commissio, committere)

commission in the 12th See also:

• REGIMENT (from Late Latin regimentum, rule, regere, to rule, govern, direct)

regiment of See also:

• FOOT

foot, then stationed in See also:

• INDIA
• INDIA, FRENCH

India, where he rendered valuable assistance in the See also:

• GREAT

great trigonometrical survey . Failing See also:

• HEALTH

health obliged him to return to See also:

• ENGLAND
• ENGLAND, THE CHURCH OF

England; and in 1808, being then a See also:

• LIEUTENANT

lieutenant, he entered on a distinguished student career in the See also:

• SENIOR, NASSAU WILLIAM (1790-1864)

senior See also:

• DEPARTMENT (Fr. departement, from departir, to separate into parts)

department of the Royal Military See also:

• COLLEGE (Collegium)

College at See also:

• SANDHURST

Sandhurst . Shortly after he was promoted to the See also:

• RANK (O.Fr. rant or rent, mod. rang, generally connected with the O.E. and O.H.G. bring, a ring)

rank of See also:

• CAPTAIN (derived from Lat. ca put, head, through the Low Lat. capitanus)

captain . In 1814 he retired on See also:

• HALF

half-pay, and devoted the See also:

• REMAINDER, REVERSION

remainder of his See also:

• LIFE

life to scientific See also:

• RESEARCH (O. Fr. recerche, from recercher, re- and cercer, mod. chercher, to search; Late Lat. circare, to go round in a circle, to explore)

research . He died at See also:

• LONDON

London on the 26th of April 1835 . His first important contribution to scientific knowledge was the comparison of the merits of the Cassegrainian and Gregorian telescopes, from which (Phil . Trans., 1813 and 1814) he deduced that the See also:

• ILLUMINATING

illuminating See also:

• POWER [WILLIAM GRATTAN] TYRONE (1797-1841)

power of the former exceeded that of the latter in the proportion of 5 : 2 . This inferiority of the Gregorian he explained as being probably due to the mutual interference of the rays as they crossed at the See also:

• PRINCIPAL

principal See also:

• FOCUS (Latin for " hearth " or " fireplace ")

focus before reflection at the second See also:

• MIRROR (through O. Fr. mirour, mod. miroir, from a sup-posed Late Lat. miratorium, from mirari, to admire)

mirror . His most valuable See also:

• WORK

work was the determination of the length of the second's pendulum, first at London and subsequently at various stations throughout the See also:

• COUNTRY (from the Mid. Eng. contre or contrie, and O. Fr. cuntree; Late Lat. contrata, showing the derivation from contra, opposite, over against, thus the tract of land which fronts the sight, cf. Ger. Gegend, neighbourhood)

country (Phil . Trans., 1818, 1819) . In these researches he skilfully took See also:

• ADVANTAGE

advantage of the well-known See also:

• PROPERTY

property of See also:

• RECIPROCITY (Lat. reciprocus, returning back the same way, alternating, probably from re back and pro forward)

reciprocity between the centres of suspension and oscillation of an oscillating See also:

• BODY

body, so as to determine experimentally the precise position of the centre of oscillation; the distance between these centres was then the length of the ideal See also:

• SIMPLE

simple pendulum having the same See also:

• TIME (0. Eng. Lima, cf. Icel. timi, Swed. timme, hour, Dan. time; from the root also seen in " tide," properly the time of between the flow and ebb of the sea, cf. O. Eng. getidan, to happen, " even-tide," &c.; it is not directly related to Lat. tempus)
• TIME, MEASUREMENT OF
• TIME, STANDARD

time of oscillation .

As the inventor of the floating collimator, See also:

• KATER, HENRY (1777-1835)

Kater rendered a great service to See also:

• PRACTICAL

practical See also:

• ASTRONOMY (from Gr. &arpov, a star, and v ,usiv, to classify or arrange)

astronomy (Phil . Trans., 1825, 1828) . He also published See also:

• MEMOIRS

memoirs (Phil . Trans., 1821, 1831) on See also:

• BRITISH

British See also:

• STANDARDS

standards of length and See also:

• MASS (O.E. maesse; Fr. messe; Ger. Messe; Ital. messa; from eccl. Lat. missa)
• MASS, IN

mass; and in 1832 he published an See also:

• ACCOUNT
• ACCOUNT (through O. Fr. acont, Late Lat. comptum, cornputare, to calculate)

account of his labours in verifying the See also:

• RUSSIAN

Russian standards of length . For his services to See also:

• RUSSIA
• RUSSIA (Rossiya)

Russia in this respect he received in 1814 the decoration of the See also:

• ORDER
• ORDER (through Fr. ordre, for earlier ordene, from Lat. ordo, ordinis, rank, service, arrangement; the ultimate source is generally taken to be the root seen in Lat. oriri, rise, arise, begin; cf. " origin ")
• ORDER, HOLY

order of St . See also:

• ANNE (1665-1714)
• ANNE (1693-1740)

Anne; and the same See also:

• YEAR

year he was elected a See also:

• FELLOW

fellow of the Royal Society . His See also:

• ATTENTION (from Lat. ad-tendo, await, expect; the condition of being " stretched " or " tense ")

attention was also turned to the subject of See also:

• COMPASS (Fr. corn pas, ultimately from Lat. cum, with, and passus, step)

compass needles, his Bakerian lecture " On the Best See also:

• KIND (O. E. ge-cynde, from the same root as is seen in " kin," supra)

Kind of See also:

• STEEL, FLORA ANNIE (1847– )

Steel and See also:

• FORM (Lat. forma)

Form for a Compass See also:

• NEEDLE (O. Eng. ncedl; the word appears in various forms in Teutonic languages, Ger. Nadel, Dutch naal, the root being ne-, to sew, cf. Ger. nahen, and probably Lat. nere, to spin, Gr. vi)ats, spinning)

Needle" (Phil . Trans., 1821) containing the results of many experiments . The See also:

• TREATISE

treatise on " See also:

• MECHANICS

Mechanics " in See also:

• LARDNER, DIONYSIUS (1793-1859)
• LARDNER, NATHANIEL (1684-1768)

Lardner's Cyclopaedia was partly written by him; and his See also:

• INTEREST

interest in more purely astronomical questions was evidenced by two communications to the Astronomical Society's Memoirs for 1831–1833—the one on an observation of See also:

• SATURN
• SATURN [SATURNUS]

Saturn's See also:

• OUTER

outer See also:

• RING (O.E. hring; a word common to Teutonic languages; and probably cognate with the Lat. circus, Gr. KtpKOS or KpLKOS, Skt'. chakra, wheel, circle, cf. also " harangue "); in art, a band of circular shape of varying sizes, made of any material and used f

ring, the other on a method of determining See also:

• LONGITUDE (from Lat. longitudo, " length ")

longitude by means of lunar eclipses .