688 
ME. AIET’S ACCOUNT OF THE COXSTErCTIOX OF 
temperature 62° Fahrenheit, 
Iron 70 + Steel 72 exceed 2 X Steel B by +0‘^’74. 
+ — d. 
Steel 73 with Iron 70, by 48 observations, exceed Steel B by +13-97 
+ — 
Iron 70 with Steel 73, by 48 obseiwations, exceed Steel B by —16-73 
Therefore Steel 73+Iron 70 exceed 2 X Steel B by — 2‘*-76. 
These comparisons were made at mean temperature 51°-69. The coiTection for 
expansion is +3‘*-89. Hence at 62° Fahrenheit, 
Steel 73+Iron 70 exceed 2 X Steel B by +1‘^-I3. 
Solving the three equations, 
d. 
Iron End-bar No. 70 = Line-measure Steel B+0-24 
Steel End-bar No. 72= Line-measure Steel B + 0-50 
Steel End-bar No. 73= Line-measure Steel B+0-89 
But Line-measure Steel B= Bronze 28 — 0'^-66. 
Hence, finally, 
d. 
Iron End-bar No. 70= Line-measure Bronze 28 — 0-42 
Iron End-bar No. 72 = Line-measure Bronze 28 — 0-16 
Iron End-bar No. 73 = Line-measure Bronze 28 + 0-23 
For obtaining the length of another Iron End-bar No. 71, the End-bars Iron No. 70 
and Iron 71 were compared with the Iron line-measure Low Moor B : 
+ — d. 
Iron 70 with Iron 71, by 48 observations, exceed Low Moor B by —13-48 
+ — 
Iron 71 with Iron 70, by 48 observations, exceed Low Moor B by +11-95 
Therefore Iron 70+Iron 71 exceed 2xLow Moor B by — 1‘^-63. 
But Low Moor B=Bronze 28+0‘^-61: and Iron 70=Bronze 28 — 0^-42. Hence 
Iron 71=Bronze 28+l‘'-02 + 0‘>-42-l‘’-53. Or 
Iron End-bar No. 71=Line-measui-e Bronze 28 — 0*^ 09. 
These are all the End-bars whose lengths were independently determined. 
Section IX. — Closing proceedings of Official Character ; Extracts from the Final Report 
of the Commission; Extracts from the Act of Parliament legalizing thedSeio Standard; 
standard temperatures for the compared bars; disposal of the bars. 
The very elaborate comparison of Bars described in Section VI., and the careful com- 
parison of other Bars in Section VH., gave the Committee ample choice of Bai-s for 
National Standards. At the suggestion of Mr. Sheepshanks, the selection was in some 
measure guided, not only by the near approach in length to the presumed length of the 
I.ost Imperial Standard, but also by the clearness of the division and the general good 
workmanship. 
It will be remarked that no one of the Bars compared agrees preoiselg in length with 
