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XXIX. Geometry and Geometers. Collected by'V. S. Davies, 

 Esq., F.R.S. and F.S.A.* 



No. II. 



I HAVE already mentioned that there are twenty-seven 

 letters of Dr. Simson's to John Nourse in the collection 

 before me. There are also two from Simson's pupil, Dr. James 

 Moor; and three notes from Dr. Robert Smith of Cambridge 

 (the founder of the " Smith's prizes," to obtain which is now 

 quite as high a distinction as to be senior wrangler) : all of 

 which relate to Simson. To this series the present and the 

 next communications will be confined. 



Dr. Trail, in his Life of Simson, p. 26, has a passage which 

 will throw light on this correspondence. " The hesitation 

 about making additions to the Treatise of Apollonius [on Plane 

 Loci] probably contributed to the delay in printing the work, 

 which was not executed till 1749. He then met with some 

 unexpected difficulties in treating with a bookseller for the 

 sale of the whole impression, which alone prevented the pub- 

 lication at that time; and except a few copies distributed 

 amongst his friends in 1750, the book remained unpublished 

 till after his death." 



This information is founded on a letter of Dr. Simson to 

 Earl Stanhope (at least all but the statement of the actual time 

 of publication being after Simson's death ; which is a mere 

 inference, and an erroneous one), dated Sept. 10, 1750. Now 

 it appears in the course of these letters that Nourse was in 

 personal intercourse with the Earl at a period shortly after- 

 wards, and that this intercourse did not appear to be of recent 

 origin. Nothing is more likely than that the Earl at once 

 brought the matter under the notice of Nourse; for the first 

 letter of this series is dated Glasgow, Jan. 1, 1751, in answer 

 to one referred to in it, from Nourse of the " 25th Oct. last." 

 It will be seen from the first three of these letters, that the 

 Loci Plani was actually published in London almost imme- 

 diately, instead of being delayed till after Simson's death, as 

 Dr. Trail infers. A subsequent letter will also show that 

 the work " did not sell," — even in an age in which it has been 

 represented that geometry was more ardently cultivated than 

 it is in our own. 



"Glasgow, 1st Jan. 1751. 



" Sir, — I had the favour of Your letter of the 25th Octr. last in clue 

 time, and am much obliged to you, who are so good a Judge as several 

 have informed me, for the kind Opinion you entertain of any of my 



* Communicated by the Author. 

 Phil. Mag. S. 3. Vol. 33. No. 221 . Sept. 1848. P 



