144 SIMSON. 



a professor of Aberdeen, whose work, in 1612, was 

 much better, but confined to a small part only of the 

 subject. 



About the time that Dr. Simson finally published 

 the Loci Plani, he began his great labour of giving a 

 correct and full edition of the Elements. The manner 

 in which this has been accomplished by him is well 

 known. The utmost care was bestowed on the revi- 

 sion of the text; no pains were spared in collating 

 editions ; all commentaries were consulted ; and the 

 elegance and perfect method of the original has been 

 so admirably preserved, that no rival has ever yet risen 

 up to dispute with Simson's Euclid the possession of 

 the schools. The time bestowed on this useful work 

 was no less than nine years. It only was published in 

 1758. To the second edition, in 1762, he added a 

 similarly correct edition of the Data, comprising several 

 very valuable original propositions of his own, of Mr. 

 Stewart, and of Lord Stanhope, together with two 

 excellent problems to illustrate the use of the Data in 

 solutions. 



We thus find Dr. Simson employed in these various 

 works which he successively gave to the world, elabo- 

 rated with infinite care, and of which the fame and 

 the use will remain as long as the mathematics are 

 cultivated, some of them delighting students who pur- 

 sue the science for the mere speculative love of con- 

 templating abstract truths, and the gratification of fol- 

 lowing the rigorous proofs peculiar to that science; 

 some for the instruction of men in the elements, which 

 are to form the foundation of their practical applications 

 of geometry. But all the while his mind never could 

 be wholly weaned from the speculation which had in 

 his earliest days riveted his attention by its curious 

 and singular nature, and fired his youthful ambition by 

 its difficulty, and its having vanquished all his prede- 

 cessors in their efforts to master it. We have seen 

 that as early as 1715 at the latest, probably much 



