254 Account of the Life and Laloi/n 



attained to the age of twenty-one. He then went to Lon- 

 don, to seek for some occupation more suited to his genius. 

 Besides other things, he appHed to engraving under Bur- 

 ton* : and a fortunate circumstance conducted him to that 

 object for w hich nature seemed to have destined him, whicli 

 was to be the reviver and father of the instrumental part of 

 astronomy. Mathematical instruments were often brought 

 to him to be engraven : the more he examined them the 

 more he was sensible of their defects, and a secret instmct 

 made him desirous of constructing better ones. He there- 

 fore resolved to make an attempt in this line : he soon ac- 

 quired the use of the file, and made himself acquainted 

 with the metliod of turning brass, and even of grinding 

 glasses. In the year 1763 he constructed instruments for 

 Sisson, Dollond, Nairne, Adams, and other mathematical 

 instrument makers. He then established a shop on his 

 own account, in the Hay-market, about the year 1768j 

 from which he removed to Piccadilly in 1 77v5. Having form- 

 ed a design of examining all the astronomical instruments, 

 he resolved to correct those which being founded on good 

 principles were defective only in the constrviction, and to 

 set aside those which were wrong in both these respects. 



Hadley's sextant, which is so much employed in the 

 British navy, appeared to him one of the most useful, but 

 it was then veiy mrperfect; the essential parts were not of 

 sufficient strength; the centre was subject to too much 

 friction ; and the index could be moved several minutes 

 w^ithout any change bcmg produced in the position of the 

 mirror; the divisions in general were verv coarse; and Mr. 

 Ramsdcn found that the abbe de la Caille was right, when he 

 estimated at five minutes the error which might take place 

 ill the observed distances of the moon and stars, and which 



* Mr. Burton was a thermometer and barometer maker, and divider 

 of instruments. Instruments at tins period were divided by means of a 

 plate applied to them, and the divisions were in this manner marked off. 

 Mr. Burton was one of the best workmen of his time, and worked for 

 Short. Bird, and other eni'nent artists. ]VIr. Ramsden bouiid himself ap- 

 prentice to Mr. Burton for four years ; and after his time was expired 

 entered into partnership with Mr. Fairbone, who lived afterwards in 

 New-street, Shoe-lane. This partnership, however, did not long con- 

 tinue. Mr. Ramsden opened a shop on his own account in the btiand, 

 and, having married miss Dollond, became possessed of a p rt of Mr. 

 Dollond's patent for achromatic telescopes. Mr. Ransden in the course 

 of a few years removed to t;:e Hay-market, and then to Piccadilly, wiiere 

 he died in the year i8oo. Mr. Ramsden had seven children ; but none 

 of them are now alive, except one son, captain John Ramsden of the 

 East India company's service, and late commander of the Doichester.— 

 EuiroR. 



3 might 



