EPOCH 



Epoch (Gr. epoche, pause). In 

 astronomy, a date arbitrarily fixecty 

 and necessary for computing the 

 place of a heavenly body. Jan. 1, 

 1901, might, for example, be the 

 date for the definition of the posi- 

 tions of the planet Mercury, and all 

 the changes in its positions would 

 then be noted in succeeding periods 

 of time. See Chronology. 



Epode (Gr. epi, on ; ode, ode). 

 Third part of the triple system of 

 the Greek ode, which consisted of 

 strophe, antistrophe, and epode. 

 The term subsequently came to be 

 loosely used in a wider signification, 

 being applied to certain of the 

 lyrics of Archilochus and his imita- 

 tor Horace. See Ode. 



Eponym (Gr. epi, on ; onoma, 

 name ). Name of a real or fictitious 

 person, the reputed founder of a 

 country or people. Such are the 

 mythical Brutus, from whom the 

 name Britain is supposed to be 

 derived, and Hellen, the traditional 

 founder of the Hellenes or Greeks. 



Eponym Canon. Assyrian 

 chronological table. The Sumerian 

 identification of years by signifi- 

 cant local events was simplified in 

 Assyrian records by naming years 

 after official personages in an or- 

 derly sequence. The word eponym 

 is used after the analogy of the 

 Greek archon (q.v. ). The king was 

 eponym in his first year, followed 

 by his commander-in-chief, court 

 officials, city governors, and others. 

 Inaugurated in 1500 B.C. if not 

 earlier, the canon hitherto re- 

 covered comprises fragmentary 

 name-lists from Ashurbanipal's 

 Nineveh library dated continu- 

 ously from 893 to 666, and discon- 

 tinuously from 911 to 640. From a 

 supplementary list mentioning im- 

 portant events as well, an eclipse 

 record was dated by astronomical 

 calculation June 15, 763, thus 

 fixing the whole series. 



Epping. Market town and urban 

 district of Essex. It stands on 

 the summit of a hilly ridge, 382 ft. 

 above sea level, near Epping 

 Forest, 17m. N.E. of London by the 

 G.E. Ely. The church of S. John 

 Baptist (1832) was rebuilt in 1890 

 and superseded All Saints at Epping 

 Upland as the parish church in 

 1 889. Its tower was added in 1 908. 

 The town hall was built in 1863. 

 Epping has an agricultural trade, 

 while cattle fairs are held here. It 

 gives its name to a division return- 

 ing one member to Parliament. 

 Market day, Fri. Pop. 4,253. 



Epping Forest. Stretch of wild 

 woodland in Essex, England. All 

 that remains of the old Royal 

 Forest of Essex, known after the 

 13th century as the Forest of Wal- 

 tham, it consists of about 6,800 

 acres between Leytonstone, S., and 



2954 



Epping, Essex. The High Street, looking towards the 

 new parish church oi S. John Baptist 



Epping, N., with Loughton, E., and 

 Chingford, W., on high ground be- 

 tween the valleys of the Lea and 

 Roding. The best of the wooded 

 section includes Monkwood, N.W. 

 of Loughton, and Epping Thicks, 

 N.W. of Theydon Bois. Dark 

 brown fallow deer run wild ; a few 

 small roe deer were introduced 

 from Dorsetshire in 1883. The last 

 of the old red deer were removed 

 to Windsor in 1827. Rabbits are 

 numerous, and a certain number 

 of badgers, foxes, squirrels, and 

 weasels are also found. 



While the pollarded hornbeam is 

 a striking feature, there are a few 

 aged oaks, and the beech, black- 

 thorn, crab-apple, birch, willow, 

 holly, and brushwood, together with 

 gorse, broom, wild rose, and honey- 

 suckle, lend charm and variety to 

 the landscape. Of two ancient 

 camps, Ambresbury Banks, 2 m. N. 

 of Loughton, is popularly assigned 

 to Queen Boadicea ; and Loughton 

 Camp, about 11 acres, to early 

 British or pre-Roman origin. After 

 protracted legal proceedings Epping 

 Forest was secured to the public by 

 the City Corporation and the Com- 

 mons Preservation Society, at a 

 cost of 250,000, and was opened 

 by Queen Victoria, May 6, 1882. 

 It is controlled by a committee of 

 the City Corporation. There is an 

 excellent Guide by E. N. Buxton, 

 1911 ; see also The Forest of Essex, 

 R. Fisher, 1887 ; the Royal Forests 

 of England, 1905 ; and Memorials 

 of Old Essex. 1908, J. C. Cox. See 

 Essex; Forests. 



Epr cuvette (Fr., testing appar- 

 atus). Instrument for measuring 

 the strength of gunpowder. The 

 first recorded specimen is that de- 

 scribed by William Bourne in In- 

 ventions or Devises, 1578. It con- 

 sisted of a small metal cylinder to 

 which was hinged a heavy metal 

 lid, which was prevented from 

 falling by engaging with a ratchet. 

 The strength of the powder was 

 measured by firing a standard 

 weight of explosive in the cylinder 

 with the lid closed and noting the 

 angle to which the latter was raised. 



EPSOM SALTS 



In 1627 Curten- 

 bach devised a 

 small mortar, on 

 the mouth of 

 which rested a 

 heavy conical shot 

 which travelled 

 vertically up a 

 stretched wire 

 passing through 

 it. The power was 

 measured by the 

 height to which 

 the charge raised 

 this shot. In 1647 

 Nye, a master 

 gunner, proposed 

 to measure the strength of gun- 

 powder by noting the depth to 

 which bullets fired from a pistol 

 penetrated into clay. He also sug- 

 gested measuring the strength of 

 powder by the distance which a 

 heavy spherical shot travelled 

 when fired from a mortar. This 

 method was taken up by the French 

 government and the mortar was 

 called eprouvette. In 1742 a fur- 

 ther advance was made, when 

 Robins invented the ballistic pen- 

 dulum, by means of which the 

 actual velocity of a projectile could 

 be measured. About 1820 much 

 use was made by sportsmen of the 

 hinged lid eprouvette in the form of 

 a flint lock pistol. For the testing 

 of modern explosives much more 

 complicated and accurate instru- 

 ments have been designed to esti- 

 mate the various characteristics of 

 the explosives. See Gunpowder. 



Epsom. Urban district and mar- 

 ket town of Surrey, England. It is 

 14 m. S.W. of London on both the 

 L.B & S.C. and L. & S.W. Rlys. 

 It was first known for its mineral 

 springs accidentally discovered in 

 1618 by Henry Wicker when graz- 

 ing his cattle. The town became a 

 fashionable spa in the 17th century 

 and was visited by royalty and 

 London society, being especially 

 popular about 1690. S. Martin's, 

 the parish church, has works by 

 Flaxman and Chantrey. Epsom 

 College is a public school, especially 

 associated with the medical pro- 

 fession. Near the town is Lord 

 Rosebery's seat, The Durdans. 



Epsom is known for its race 

 meetings, held on the downs, which 

 stretch for some miles. Here the 

 Derby, the Oaks, and other races are 

 run and there are several large rac- 

 ing stables around. The town has 

 some industries and is an outer sub- 

 urb of London. It gives its name 

 to a division sending one member 

 to Parliament. Pop. 19,150. See 

 Derby ; Horse-racing ; Oaks. 



Epsom Salts. Magnesium sul- 

 phate (MgS0 4 7H 2 O). It crystallises 

 in small rhombic prisms, and forms 

 a useful saline purgative. 



