_Cost of Laying 100 Yards of Double Conductor of Bare Copper carried
on Insulators in a Culvert._
---------------------------+----------+---------+---------+
Area in square inches | 0·25 | 0·5 | 1·0 |
Area in square millimetres | 161·25 | 322·5 | 645 |
Weight of copper in lb. | | | |
per 100 yards | 576 | 1153 | 2306 |
Cost of copper at | | | |
7¾_d._ per lb. | £18 15 0| 37 5 0| 74 10 0|
Laying | 9 0 0| 9 12 0| 9 12 0|
Insulators | 0 4 6| 0 4 6| 0 4 6|
6 surface boxes and | | | |
connections | 10 0 0| 10 0 0| 10 0 0|
Culvert, 18 inches × | | | |
12 inches, for | | | |
two lines conductor, | | | |
in brickwork | 53 8 0| 53 8 0| 53 8 0|
and cement, replacing | | | |
pavement | | | |
Engineers and | | | |
superintendence | 6 0 0| 10 0 0| 10 0 0|
+----------+---------+---------+
Total | £97 7 6|120 9 6|157 14 6|
Extra for copper at | | | |
9½_d._ per lb. | 3 5 0| 8 10 0| 17 0 0|
+----------+---------+---------+
Total |£100 12 6|128 19 6|174 14 6|
Cost of copper per lb. | | | |
laid complete | 42_d._ | 27_d._ | 18·2_d._|
Current in ampères | 90 | 180 | 360 |
Cost per ampère | 1 2 3| 0 14 5| 0 9 8|
---------------------------+----------+---------+---------+
---------------------------+---------+---------+-------------
Area in square inches | 2·0 | 2·55 | 3·00
Area in square millimetres | 1290 | 1645 | 1935
Weight of copper in lb. | | |
per 100 yards | 4612 | 6125 | 6918
Cost of copper at | | |
7¾_d._ per lb. |149 0 0|190 0 0|224 0 0
Laying | 9 15 0| 9 15 0| 10 0 0
Insulators | 0 4 6| 0 4 6| 0 4 6
6 surface boxes and | | |
connections | 10 0 0| 10 0 0| 10 0 0
Culvert, 18 inches × | | |
12 inches, for | | |
two lines conductor, | | |
in brickwork | 53 8 0| 53 8 0| 53 8 0
and cement, | | |
replacing pavement | | |
Engineers and | | |
superintendence | 10 0 0| 10 0 0| 15 0 0
+---------+---------+-------------
Total |232 7 6|263 7 6|312 12 6
Extra for copper at | | |
9½_d._ per lb. | 34 0 0| 43 10 0| 51 0 0
+---------+---------+-------------
Total |266 7 6|306 7 6|363 12 6
Cost of copper per lb. | | |
laid complete | 13·8_d._| 12_d._ | 12 6_d._
Current in ampères | 720 | 910 | 1080
Cost per ampère | 0 7 5| 0 6 9| 0 6 8½
---------------------------+---------+---------+-------------