Bureau of Foreign and Domestic Commerce, "Construction Activity in the United States 1915-1937," 1938.

B. Percentage Distribution of Gainful Workers in Manufacturing, Mechanical, and Construction Industries in the United States from 1870 to 1930.

Note that in 139A above, the division at the very top is labelled "Manufacturing, Mechanical and Construction." This chart is a further break-down of that one component. In the same way each of the component parts of 139A could be divided.

GRAPHIC PRESENTATION

-- LEG END --

I I Unshaded areas show supplemental KVAXVVj Available watar for soil havioq

■ ' water re^uirod Kr/ii\wiiM nfiltration capoci^Y o* OS ifKh per do^

IHHH "^ter requiredlaches permoolh. t^^t^y>^ Do liocb per day

I. ./' "l Actual roirifoll t '.'/.tS'/W^ Oo 1 5 inches per day

National Resources Board, "Report of Water Planning Committee, Part III," 1Q34.

SCALE .7

Supplemental Water Required to Provide 18 Inches Total Water for Crop Use Per Day from May to October on Soils Having Various Infiltration Capacities in Atlanta, Georgia, and Bismarck, North Dakota, from 1930 to 1932.

1. These cities were only two of several for which this analysis was made.

2. The necessity for reservoirs and dams is clearly shown in an effective form.

COMPARISON OF COMPONENT BAR CHARTS

•^te

...» \i, ^

-S

I-

I.

1.-"

1-3

M.OCM TOTAL

<«t*g r^wLT wCDwt wa howtw

O iliOO'lt ntClaT«4i 0> BIT

AytBAti rAKLY Mirr h» womtm

$SI •«

Land Utilization Comiriittfp. New York Building Congress, Arthur C. HoUlfn, Chairman. SCALE .8