Summarizing we have the following cost:

Materials—
Cement, 5.6 bags at $0.62$3.472
Gravel (excavating and screening)0.421
Hauling gravel and sand0.223
———
Total, materials$4.116
Labor—
Mixing concrete$0.819
Transporting concrete0.326
Depositing concrete1.394
Setting and moving forms0.498
———
Total, labor$3.037
Grand Total$7.153

COST OF CONCRETE WORK IN LINING NEW YORK RAPID TRANSIT SUBWAY.—The costs given here refer alone to the concrete work in constructing the jack arch and steel beam lining of the original standard subway. Figure 143 shows the character of this construction. Arch panel forms were set up between the wall beams and hung from the floor beams and filled behind and above with 1-2-4 trap rock concrete. The form panels were used over and over and the concrete was machine mixed. Common labor was paid $1.50 per 8-hour day; foremen, $3; carpenters, $3; enginemen, $3.50; and masons, $4. The costs cover three sections and are in each case the averages for the whole section. They are, we believe, the only itemized costs that have been published for concrete work on this road.

Two-Track Subway.—In this section of two-track subway there were 8,827 cu. yds. of foundation concrete and 6,664 cu. yds. of concrete in wall and roof arches. The two classes of work cost as follows:

Fig. 143.—Cross-Section of New York Rapid Transit Subway.

Foundations—Total.Per cu. yd.
Labor mixing$ 4,669$0.53
Labor placing5,1420.58
Materials and plant2110.02
Cement, sand, stone, etc.30,7193.48
———————
Total$40,741$4.61
Roof and side walls—
Labor mixing$ 5,444$0.82
Labor placing5,6230.84
Labor setting forms14,7462.21
Labor plastering arches4310.06
Materials and plant1,1760.18
Cement, sand, stone, etc.23,8883.58
———————
Total$51,308$7.69

Averaging the work we have 15,491 cu. yds. of concrete placed at a cost of $5.94 per cu. yd.

Four-Track Subway.—On two sections of four-track subway the labor cost of mixing and placing concrete similarly divided was as follows: