620 MISCELLANEOUS PAPERS. 



No. 14. Sir George Shuckburg's scale (179G) ; a Hue measure, upou a 

 brass bar l.i iuclies broad, 0.42 of an inch thick, and 67.7 inches long. 

 Space compared, inch to 36 inches. Phil. Traus., 1798, p. 133, and 

 Mem. Ro3\ Ast. Soc, vol. 9, pp. 84-85. 



No. 15. Ditto. Space compared, 10 inches to 46 inches. 



No. 16. Ordnance yard lA (1827); a line measure, upon an irou bar 

 1.45 inches broad, 2.5 inches deep, aud rather more than 3 feet loug. 

 Measurement of Lough Foyle Base, pp. 71, 82, and [28]. 



No. 17. Ordnance yard 2A( 1827). Similar to lA. Same authorities. 



No. 18. Captain Kater's Eoyal Society yard (1831); aline measure, 

 upon a brasb plate 0.07 of an inch thick. Phil. Trans., 1831, p. 345. 



No. 19. The Eoyal Astronomical Society's standard scale (1834) ; a 

 line measure, upon a brass tube 1.12 inches exterior diameter, 0.74 of 

 an inch interior diameter, and 63 inches long. The central yard was 

 the space compared. Mem. Boy. Ast. Soc, vol. 9, p. 09. 



No. 20. "Colonel Lambton's standard;" a line measure, upon a brass 

 plate 0.92 of an inch broad, 0.21 of an inch thick, aud QQh inches long ; 

 strengthened by an edge bar of nearly the same breadth, but only 0.08 

 of an inch thick. Phil. Trans., 1821, p. 88, and Mem. Roy. Ast. Soc, 

 vol. 9, pp. 82-83. 



The authorities for the comparisons given in the various columns of 

 the table are as follows : 



Column A. Comparisons by Mr. George Graham. Phil. Trans., 1743, 

 pp. 187 and 547-550. 



Column B. Comparisons by Sir George Shuckburgh. Phil. Trans., 

 1798, pp. 167-181. 



Column C. Comparisons by Captain Kater, Phil. Trans., 1818, p. 55, 

 and 1821, p. 91. 



Column D. Comparisons by Captain Kater. Phil. Trans., 1830, p. 

 377, and 1831, p. 347. 



Column E. Comparisons by Francis Baily, esq. Mem. Eoy. Ast. Soc, 

 vol. 9, p. 145. 



Column F. Comparisons by Francis Baily, esq. Mem. Eoy. Ast. Soc, 

 vol. 9, p. 120. 



Column G. Values adopted by E. Sheepshanks, esq. Phil. Trans., 

 1857, p. 661. 



The values used by Mr. Sheepshanks in 1848 to determine the length 

 of the present Imperial standard yard were Nos. 14 D, 15 F, 16 and 17 

 G, and 18 D. 



It will be observed that several different units are employed in the 

 various columns of the table, and care must be taken to allow for that 

 circumstance when comparing numbers not situated in the same column. 



