Good maps must of course be obtained. Government contour maps when available will assist materially in selecting roads that will come within a ruling grade. On these maps will first be noted the trunk line terminals and other ruling points. The trunk lines should be as direct as practicable from one ruling point to the next. An endeavor should be made to have the roads with the greatest travel upon them the straightest, so that the total future haul may be a minimum. The roads having the greatest travel will usually be those connecting the largest cities of the state or articulating with roads leading to large cities of other states. Then will be drawn in branch lines and detours so that when the plan is complete every county seat, every village of more than 1000 inhabitants, and every manufacturing, scenic, and pleasure resort of importance will have been reached, as well as connections with the main roads of adjacent states.
This will form a tentative system. Observation upon the roads themselves will now be necessary. A reconnaissance survey may be made quite rapidly from an automobile. Two men are necessary. The engineer will ordinarily drive while the topographer will be supplied with a clip board and ruled sheets of paper. The straight line up the center of the sheet represents the roadway. Small squares on the sheets represent distances and areas. The scale should be made according to the work. On a road with few houses and few topographical features to be recorded 1 inch to the mile might be sufficient. With more houses, and other features, 1 inch to the quarter mile might be none too much. As speedometers (odometers) usually read to a tenth of a mile cross-section paper with ten smaller divisions equal to one larger is convenient. The engineer will observe features and the recorder will record them as the machine is driven along. The miles may be marked off on the sheets ahead then very quickly by a series of notations, such as a
for a farm house, a dot with a roof over it
for a school house, a steeple or cross on top
makes a church. A crossing wagon road
, railroad track