38 



instruments; and I reflect with pleasure on the opportunities I 

 have enjoyed of cultivating an acquaintance and friendship with the 

 person that, of all others, has most contributed to their improve- 

 ment. For I am sensible that if my own endeavours have in any 

 respect been to the advantage of astronomy, it has principally been 

 owing to the advice and assistance given me by our worthy member 

 Mr. George Graham, whose great skill and judgment in mechanics, 

 joined with a complete and practical knowledge of the uses of 

 astronomical instruments, enable him to contrive and execute them 

 in the most perfect manner. The gentlemen of the Royal Academy 

 of Sciences, to whom we are so highly obliged for their exact 

 admeasurement of the quantity of a degree under the arctic circle, 

 have already given the world very convincing proofs of his care 

 and abilities in those respects ; and the particular delineation which 

 they have lately published of the several parts of the Sector which 

 he made for them, hathgnow rendered it needless for me to enter 

 into any minute description of mine at Wanstead, both being con- 

 structed upon^the same principles, and differing in their component 

 parts chiefly on account of the different purposes for which they 

 were intended." 



It is worthy of remark that this same Zenith Sector was used 

 at the Cape of Good Hope between the years 1838 and 1848, for 

 observations connected with the measurement of an arc of the 

 meridian, and is now preserved at Greenwich. 



Graham also gave'much attention to the subject of Magnetism; 

 he discovered the diurnal variation of the compass, and made 

 many observations with the dipping needle, throwing much light 

 on this obscure but interesting subject. He also investigated with 

 acuteness and labour, the standards of weights and measures 

 in the Exchequer, and others which were kept for public purposes; 

 but it is not needful to allude to them further than to show the 

 range and importance of his researches. 



In connection with his business as a watch-maker, some 

 characteristic anecdotes have come down to us. It is related that 

 on the occasion of a person applying to him on the subject of a 

 watch upon which his name had fraudulently appeared, he at once 



