The first three hundred seventy-five (375) of these bonds will be payable July 3, 1923. Three hundred and seventy-five (375) more will be payable on July 3rd of each year thereafter until the final payment in 1962. Interest payments are to be made semi-annually.

The Constitutional Amendment adopted July 1, 1919, provided for a third State Highway Bond Issue in the sum of $40,000,000. These consist of forty thousand (40,000) bonds of the par value of $1,000 each. The interest rate is four and one-half per cent, payable on January 3rd and July 3rd of each year. The bonds become due and payable in parcels of one thousand (1,000) commencing July 3, 1926 and ending July 3, 1965.

Routes and Mileage

The following routes and mileage of State highways, under the three bond issues, were proposed to the voters:

*Route 30 has been abandoned, and Route 21 extended to cover approximately same mileage.

STANDARD SECTIONS OF CALIFORNIA ROADS

Pages 27 to 30 show typical sections that were adopted from time to time by the California Highway Commission for the building of the State highways.

There is also shown on Page 30 typical cross section of the pavement being built by the State of Washington.

Table No. 1 (Page 31) gives the width and thickness of various State pavements.

is difficult to make comparisons because the different States have various standard widths and also widths of pavements used for special localities. The standard width of the California pavements is 15 feet on trunk roads with increased widths on mountain grades and approaching cities. Some 8-foot widths have also been built.

Out of the thirty-five States listed, three are shown as building narrower pavements. They are Delaware (14 feet to 18 feet), Mississippi (9 feet to 18 feet) and Nevada (9 feet to 16 feet). Maryland and Texas have a fifteen to eighteen-foot pavement. The remaining thirty States build wider pavements than California.

California has recently increased the standard thickness of its slab from 4 to 5 inches and reinforced it. No other State is reported as building a standard pavement as thin as either four or five inches with the exception of Georgia which has a five-inch thickness of reinforced slab similar to California. All of the rest build thicker pavements. Reinforcing

does not materially add to the strength of the pavements. It does, however, hold together the fragments when it is broken.

The mixture now used in California is one of cement, two of sand and four of stone. One (Mississippi) of the thirty-five States uses a leaner mixture. Nine others used a similar mixture to California. The remaining twenty-five States use richer mixtures.

Table No. 2 (Page 32) shows details in which different States build their pavements as to reinforcement, joints, method of curing, etc. Most of them require a longer period of curing than California. Of the forty-eight States shown in the table, thirty-five require expansion joints in the construction of the concrete slab. The others either do not require it or do not specify. The expansion joints in roads in Washington and Oregon are placed usually thirty feet apart and filled with elastite. This filler is one-quarter of an inch thick when placed in the summer and thicker when placed in the cooler months. It gives a finished appearance to the work.

In making the concrete in Washington, the different aggregates are graded in size and usually washed.

In the very important feature of trueness of surface of the pavement when finished, California requirements are as exacting as those used in most other States. It allows for a variation of a quarter of an inch in five feet. New Jersey allows a quarter of an inch in ten feet, as does Pennsylvania. A smooth surface avoids road shock and thus extends the life of the pavement. The most exacting results should be insisted on in this particular. The following data relates to Southern California County Concrete Highways in 1920: