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 equally a fellow. We have, too, his own reference to himself as a landsman, with an apology for his seeming presumption in writing of nautical matters. But, in fact, with the exception of his account of the voyage of 1589 (published separately in 1599, and also in Hakluyt's ‘Principal Navigations,’ II. ii. 143), all his nautical writings relate to navigation considered as a branch of mathematics. It is on these that his fame rests. He did, in fact, effect a complete revolution in the science, bringing to it for the first time a sound mathematical training.

From a very early date navigators had used a plane chart, in which the meridians, represented by parallel straight lines, were crossed at equal distances by parallels of latitude, the degrees of latitude and longitude being thus shown of equal length. Such a chart had not only the great fault of grossly distorting the ratio of length to breadth, but, from the navigator's point of view, the still greater one of not permitting the course from one place to another to be laid off at sight. What was wanted was a chart which would show as a straight line the curve drawn on a globe cutting each meridian at a constant angle. Such a curve, it may be said, is called by navigators a rhumb, or rhumb line. Now, a year or two before Wright was born, Mercator in Holland had attempted to draw such a chart (1556) by lengthening the degrees of latitude in some rough proportion to the lengthening of the degrees of longitude, apparently by noting on the sphere where the rhumbs cut the meridians; but these charts were not thought much of by navigators, and when Wright first went to sea he found the old plane chart still in common use. The problem, as it appeared to him, was to devise a chart in which the degrees of latitude should be lengthened in the same proportion as the degrees of longitude were when the meridians were represented by parallel straight lines.

The solution of this problem is now easy by the use of the integral calculus, but in 1589 very little was known of the doctrine of limits, even in its most elementary form. What little was known Wright applied; he arrived at a correct and practical answer to the question, and constructed a table for lengthening the degrees of latitude such as is now commonly printed as a ‘table of meridional parts.’ Wright's first table was very rough, and he himself was doubtful of its practical value; but when Hondius in Germany without acknowledgment, and Thomas Blundeville [q. v.] in England with acknowledgment (Exercises, 1594, p. 326 b), adopted it, and others were preparing to put the method forward as their own, he conceived the time had come to claim it publicly, and in 1599 published ‘Certaine Errors in Navigation, arising either of the ordinarie erroneous making or using of the sea chart, compasse, crosse staffe, and tables of declination of the sunne and fixed starres, detected and corrected’ (sm. 4to, London, printed for Valentine Simms; 2nd edit. 1610, with additions; 3rd edit. [see ], 1657; there is a beautiful copy of the rare first edition in the Grenville Library, British Museum. In this the question of the chart was fully and clearly discussed, once for all, as a mathematical problem. Practically speaking, the so-called Mercator's charts in use at the present time are drawn on the projection laid down by Wright.

Wright is said to have been tutor to Prince Henry, a report which seems corroborated by the dedication to the prince of the second edition of the ‘Certaine Errors.’ It is also said that he conceived the plan of bringing water to London by a canal, which was known as the New River, ‘but by the tricks of others he was hindered from completing the work he had begun.’ He was appointed by Sir Thomas Smith (Smythe) [q. v.] and (Sir) John Wolstenholme [q. v.] to lecture on navigation, which he did in Smythe's house, till in 1614 the matter was taken up by the court of the East India Company, and Wright was appointed by them at a salary of 50l. a year to lecture on navigation, to examine their journals and mariners, and to prepare their plots. He died in London in 1615, ‘vir morum simplicitate et candore omnibus gratus.’ He was married and left one son, Samuel, who entered at Caius College in 1612, and died apparently in 1616.

Besides the ‘Certaine Errors’ and the ‘Voyage to the Azores,’ Wright published: 1. ‘The Haven finding Art, or the way to find any Haven or place at Sea by the latitude and variation’ (1599, sm. 4to); an adaptation and extension of Simon Stevin's ‘De Havenvinding,’ which was translated into Latin by the elder Groot under the title of ‘Λιμενευρετική sive portuum investigandorum ratio.’ Bearing in mind that there was then absolutely no way of determining the longitude at sea, the proposal was to determine a position by the latitude and variation of the compass, assumed as constant in the same place, which is only approximately true for a few years. 2. ‘The Description and Use of the Sphære’ (1613, sm. 4to). 3. ‘A Short Treatise of Dialling’ (1614, sm. 4to). 4. ‘A Description of