THE NEW NATIONAL STANDAED OF LENG-TH, AND ITS PEINCIPAL COPIES. 
On my application to the Lords Commissioners of the Treasury, the ruined Imj)erial 
Standard was in March 1844 placed in the hands of Mr. Baily ; and the experiments 
on its expansion are here detailed after the others. 
It will be remarked that some comparisons are made with the temperature rising and 
some with the temperature falling. There appears to be no sensible difference in the 
results. 
Description and length 
of bar. 
Thermometer-reading. 
Change of 
length. 
Modulus for 
1° Fahr. 
Modulus deduced 
from the compound 
expansion. 
First. 
Seeond. 
Gun-metal (?) No. 1,_^ 
40 inches. 
46-90 
47'20 
33-70 
94-63 
67-05 
98-25 
94-37 
94-65 
67-05 
46-50 
div. 
780-00 
716-00 
933-50 
437-50 
285-00 
-0000095970 
95959 
96823 
100209 
87674 
' 
-0000094859 
Gun-metal No. 2, j 
40 inches. 
46-90 
97-15 
41-55 
97-15 
42-25 
95-55 
771-50 
881-00 
799-70 
-0000097059 
101447 
93621 
Gun-metal No. 3, 
40 inches. 
38-35 
96-95 
32-00 
98-30 
45-35 
97-85 
935-30 
817-60 
1005-00 
-0000098627 
100168 
96482 
Gun-metal No. 4, f 
40 inches. \ 
33-63 
99-05 
99-05 
42-95 
994-03 
818-23 
-OOOOO96O86 
92204 
Brass tube, 40 inches. 
32- 70 
98-52 
170- 25 
35-15 
98- 67 
171- 50 
118-10 
34-35 
106-35 
183-75 
99- 02 
33- 65 
97-23 
176-17 
98-52 
170- 25 
32-65 
98- 67 
171- 50 
118-10 
40-93 
106-35 
183-75 
99- 02 
37-20 
97-23 
176-17 
100-45 
1047-75 
1179-10 
2233-85 
1020-50 
1188-83 
858-83 
1283-60 
1181-30 
1302-10 
1442-95 
1004-00 
1033-67 
1353-60 
1293-17 
-0000100632 
103932 
103548 
101364 
103206 
102170 
103174 
103738 
106351 
107661 
102699 
102778 
108405 
108132 
■ 
■ 
. -0000102345 
102433 
103745 
105092 
105554 
105892 
Brass bar, 40 indies. < 
i 
40-60 
98- 91 
45-00 
99- 72 
177-95 
98-35 
35-05 
100-17 
176-92 
88-75 
98- 91 
45-35 
99- 72 
177-95 
98-35 
37-45 
100-17 
176-92 
88-75 
35-80 
890-55 
828-75 
858-26 
1267-49 
1307-65 
940-50 
1004-40 
1246-72 
1446-27 
805-90 
-0000096550 
97818 
99154 
102425 
103852 
97629 
97491 
102690 
103697 
96217 
' 
. -0000101079 
101155 
100310 
100890 
Steel bar, 40 inches. < 
L 
37-25 i 97-13 
97-13 ! 43-75 
33-25 89-22 
89-22 176-10 
176-10 100-58 
100-58 34-67 
559-47 
520-07 
516-35 
891-03 
787-24 
620-73 
-0000059056 
61592 
58321 
64836 
65900 
59537 
■ 
. -0000062284 
> 62935 
4 o 2 
