GELLIBRAND. 



father. His sole attention was now de- 

 voted to the mathematics, in which he 

 made such proficiency, at the time of 

 his taking his degree of M. A. in 1623, 

 that he attracted the notice and friend- 

 ship of several able mathematicians who 

 flourished at that time, particularly of 

 the celebrated Henry Briggs, then Savil- 

 lian professor of geometry at Oxford. 

 While he continued in the pursuit of 

 these studies, the professorship of as- 

 tronomy in Gresham College, London, 

 becoming vacant by the death of the in- 

 genious Edmund Gunter, Mr. Briggs en- 

 couraged Mr. Gellibrand to become a 

 candidate for that chair. Accordingly 

 he proceeded to London, with strong 

 testimonials in his favour from the Presi- 

 dent, Vice President, and Fellows of his 

 College, and other active friends, and 

 was chosen to fill that post by the elec- 

 tors, in the month of January, 1626. 

 From that time he lived, as he had done 

 before, in a close intimacy with Mr. 

 Briggs, who took great pleasure in com- 

 municating to him his mathematical opi- 

 nions and discoveries, and at the time of 

 his death confided to him the task of 

 completing his " British Trigonometry," 

 which he did not live to finish. While 

 Mr. Gellibrand was preparing that work 

 for the press, he was cited, together 

 with his servant William Beale, into the 

 High Commission Court, by Doctor Laud, 

 then Bishop of London, on account of an 

 almanac for the year 1631, which Beale 

 had published with the approbation of 

 his master. In this almanac, the Popish 

 saints usually put into the calendar were 

 omitted, and the names of other saints 

 and martyrs, mentioned in " Fox's Acts 

 and Monuments of the Church/' were 

 inserted, as they stood in Fox's calendar. 

 This circumstance gave great offence to 

 the haughty prelate, and determined him 

 to prosecute them for a measure, which 

 he considered to be an unequivocal evi- 

 dence of their Puritanism. But when 

 their cause came to a hearing, by shew- 

 ing that what they had done was no in- 

 novation, and pleading that they had no 

 ill intention, they were acquitted by 

 Archbishop Abbot and the whole court, 

 Laud only excepted ; which was made an 

 article of accusation against the last-men- 

 tioned prelate at his own trial. This 

 prosecution proved the means of retard- 

 ing the publication of Mr. Briggs' work ; 

 but when Mr. Gellibrand had escaped 

 from the vengeance of Laud, he again 

 applied to the completion of his friend's 

 Design, and having added to it a preface, 



and the application of the logarithms to 

 plane and spherical trigonometry, &c. 

 constituting the second book of the work, 

 the whole was printed at Gouda in Hol- 

 land, under the care of Adrian Vlacq, in 

 1636. It was eatitled " Trigonometria 

 Britannica, sive de Doctrina Triangulo- 

 rum, Libri duo, &c." folio. 



Mr. Gellibrand, however, though an 

 industrious mathematician, had not suffi- 

 cient comprehension of mind to admit the 

 evidence, which Galileo had lately pro- 

 duced in support of the Copernican sys- 

 tem. This appears from the account 

 which he has given of a conversation 

 which he had, when he went over to 

 Holland on the business of printing the 

 Trigonometry ,with Lansberg,an eminent 

 astronomer in Zealand, who insisted on 

 the truth of that system. " This, which 

 he was pleased to style a truth," says 

 our author, " I should readily receive as 

 an hypothesis, and so be easily led on 

 to the consideration of the imbecility of 

 man's apprehension, as not able rightly 

 to conceive of this admirable opifice of 

 God, or frame of the world, without 

 falling foul of so great an absurdity. 

 Yet, sure I am, it is a probable induce- 

 ment to shake a wavering understand- 

 ing-" 



From Mr. Gellibrand's situation at 

 Gresham College, and his intercourse 

 with the lovers of mathematical studies, 

 he had an opportunity of contributing 

 some pieces, mentioned below, to the 

 imp"ovement of navigation, which sci- 

 ence would probably have been farther 

 benefitted by him, had he not been imma- 

 turely carried off by a fever in 1636, when 

 in the fortieth year of his age. That his 

 mathematical knowledge was consider- 

 able, and usefully applied, is sufficiently 

 apparent from the treatises which he left 

 behind him, and the estimation in which 

 he was held by the most respectable 

 men of science among his contempora- 

 ries, both at Oxford and London. But he 

 is entitled more to the praise of close and 

 unwearied industry than of invention or 

 genius. Besides his part of the " Tri- 

 gonometria Britannica," he was the au- 

 thor of " An Appendix concerning Longi- 

 tude," subjoined to Captain Thomas 

 James's Voyage for the Discoverv of the 

 North West Passage, 1633, quarto; " A 

 Discourse mathematical, on the varia- 

 tion of the Magnetic Needle, together 

 with the admirable diminution lately dis- 

 covered," annexed to Wright's " Errors 

 in Navigation Detected, &c." 1635, 



