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CHAPTER VI.

Quantities of Materials.

I. Volumes from Cross Sections.

3. Volumes of Continuous Prismoids.

b. Volumes from Field Notes direct.

Form of Field Notes.

In the particular case we are using for illustration let us suppose the cross-section notes in our field book to be as follows:
Station 0— 34.0
–––
12.0		 c
–––
16.0		 37.0
–––
14.0
Station 1— 35.2
–––
12.8		 c
–––
17.0		 38.5
–––
15.0
Station 2— 37.3
–––
14.2		 c
–––
17.8		 39.7
–––
15.8
Station 3— 39.1
–––
15.4		 c
–––
18.8		 41.2
–––
16.8
Station 4— 40.9
–––
16.6		 c
–––
20.2		 43.6
–––
18.4

which is the form of all cross-section notes and in which the numbers above the horizontal lines are the number of feet out on each side of the Center line that the slopes of the sections intersect the surface of the ground, while the figures under the lines give the height of those points above the finished grade of the road-bed. For example, at Station 0 the surface of the ground at the Center line at this section is 16.0 feet above the finished grade while the side slopes, which have a slope ratio of 1½ to 1, intersect the surface of the ground, the right hand slope at 37.0 and the left hand slope at 34.0 feet respectively from the Center line, while the elevation of these point of intersection are 14.0 ft. and 12.0 respectively above the finished grade of road-bed.

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