covered with white paper, on which a pen having a slow movement in the direction of the axis of the cylinder describes a continuous spiral. This pen is deflected through the agency of an electromagnet every second, and thus the seconds of the clock are recorded on the chronograph by offsets from the spiral curve. An observer having his haml on a contact key in the same circuit can record in the same manner his observed times of transits of stars. The method of determination of difference of longitude is, therefore, virtually as follows. After the necessary observations for instrumental corrections, which are recorded only at the station of observation, the clock at A is put in connexion with the circuit so as to write on both chronographs, namely, that at A and that at B. Then the clock at B is made to write on both chronographs. It is clear that by this double operation one can eliminate the effect of the small interval of time consumed in the transmission of sig- nals, for the difference of longitude obtained from the one chronograph will be in excess by as much as that obtained from the other will be in defect. The determination of the personal errors of the observers in this delicate operation is a matter of the greatest importance, as therein lies pro-
bably the chief source of residual error.
Since the article Figure of the Earth was written, considerable additions to the data for the determination of the semiaxes of the earth have been obtained from India, viz., a new meridian are of 20°, the southern point of which is at Mangalorc, together with several arcs of longitude, the longest of which, between Bombay and Nizagapatam, extends over 10° 30’. The effect of the accession of these new measures is to alter the figure previously given to the following : the semiaxcs of the spheroid best representing the large arcs now available are
a=‘2U926'202; c=20S5~f895; c :a=292°~f65 : 293465.
This value of the major semiaxis exccetls that previou.sl_v given by 140 feet, whereas the new polar seniiaxis is less than the old by ‘.226 feet. 11' we admit that the figure may possibly be an ellipsoid (not of revolution), then the investigation leads us, through the solution of 51 equations, to these values of the semiaxes—
| a=209266‘39, |
| b=:7_09'.7.5105, |
| c=2085~f4()7. |
The greater axis of the equator lies in longitude 8° 15' west of Greenwich, a meridian which passing through Ireland and Portugal cuts off a portion of the north-west corner of Africa, and in the opposite hemisphere cuts off the north-east corner of Asia. The apparent ellipticity of the equator is much reduced by the addition of the new data, and it would not be right t.o put too much confi- dence in the ellipsoidal figure until many more arcs of longitude shall have furnished the means of testing the theory more decisively than can be done at present. (See I’hz'l0s0])ln'cal .l[u_r]u:im', August 1878.)
GEOFFREY OF MONMOUTH (1110?–1154), one of the most famous of the Latin chroniclers, was born at Monmouth early in the 12th century. Very little is known of his life. He became archdeacon of the church in Monmouth, and in 1152 was elected bishop of St Asaph. He died in 1154. Three works have been attributed to him—the C/u'oni— con sive Ilisloria Ilritonznn; a metrical LifeumlI’rrq)kec1'es of Jlerlin ; and the Cbmpendium Gaigfrerfi Je C'orporc C’/uisti et Srtr:ramcnto Euc/mristire. Of these the first only is genuine; internal evidence is fatal to the claims of the second ; and the Comlgenclimn is known to be written by Geoffrey of Auxerre. The Ilistoria Britomzm appeared in 1147, and created a great sensation. Geoffrey professed that the work was a translation of a Breton work he had got from his friend Walter C-ilenius, archdeacon of Oxford. It is highly probable that the Breton work never existed. The plea of translation was a literary fiction extremely common among writers in the .Iiddle Ages, and was adopted to give a mysterious importance to the communications of the author and to deepen the interest of his readers. We may compare with this Sir Walter Scott’s professed quota- tions from “Old Plays,” which he wrot.e as headings for chapters in his novels. If Geoffrey consulted a Breton book at all, it would probably be one of the Arthurian romances then popular in Armorica. llis history is a work of genius and imagination, in which the story is told with a Defoe-like minuteness of detail very likely to impose on a credulous age. It is founded largely on the previous histories of Gildas and the so-called N ennius; and many of the legends are taken direct from Virgil. The history of Merlin, as embodied in the Ilistorirz, is found in Persian and Indian books. Geoffrey's imagination may have been greatly stimulated by local English legends, especially in the numerous stories he gives in support of his fanciful derivations of names of places. Whatever hints Geoffrey may have got from popular tales, and whatever materials he may have accumulated in the course of his reading, the Jlistoriu is to be thought of as largely his own creation and as forming a splendid poetical whole. Geoffrey, at all events, gave these stories their permanent place in litera- ture. We have sufficient evidence to prove that in Wales the work was considered purely fabulous. (See Giraldus C'ambrcn.sis, Itincrarium C {nub-fire, lib. i., c. 5, and Cam- lzri/L’ Dcscfiptiu, c. vii.) “that fabler (Geoffrey) with his fables shall be straightway spat out by us all.” Geoffrey’s 1[i.-torict was the basis of a host of other works. It was abridged by Alfred of Beverley (1150), and translated into Anglo—.'orman verse, first by Geoffrey Gaimar (1154), and then by Wace (1180), whose work, Li Bomrms de I};-Hf, contained a good deal of new matter. Early in the 13th century was published Laya1non’s Brut ; and in 1278 appeared ltobert of Gloucester’s rhymed C/n~om'cle qfEn_r/land. These two works, being written in English, would make the legends popular with the common people. The same influence continued to show itself in the works of Roger of Wendovcr (1237), Matthew Paris (1259), Bartholomew Cotton (1300?), Matthew of Westminster (1310), Peter Langtoft, llobert de Brunne, Ralph Higden, John Harding, Robert Fabyan (1512), Itichard Grafton (1569), and Raphael Holinshed (1580), who is especially important as the immediate source of some of Shakespeare’s dramas. A large part of the introduction of .Iilton’s 1[istor_z/ qf If-nglaml consists of Geoffrey’s legends, which are not accepted by him as his- torical. The stories, thus preserved and handed down, have had an enormous influence on literature generally, but especially on English literature. They became familiar to the Continental nations; and they even appeared in Greek, and were known to the Arabs. With the exception of the translation of the Bible, probably no book has furnished so large an amount of _literary material to English writers. The germ of the popular nursery tale, Jae]: the (;'iant—1i'z'ller, is to be found in the adventures of his Corineus, the com- panion of Brutus, who settled in Cornwall, and had a desperate fight with giants there. Goemagot, one of these giants, is said to be the origin of Gog and .lagog——t’0 efligies formerly exhibited on the Lord Mayor's day in London, which are referred to in several of the English dramatists, and still have their well-known representatives in the Guildhall of the city. Chaucer gives Geoffrey a place in his “House of Fame,” where he mentions “Englyssh Gaunfride” (Geofi'rr.-y) as being “ besye for to here up Troye.”
place in literature. The Arthur of later poetry is a grand ideal personage, seemingly unconnected with either space or time, and performing feats of extraordinary and super- lnnnan valour. The real Arthur—if his historical existence
And William of Newbury says , is to be r:onceded—-was most probably a Cumbrian or