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be set to accurately fit the curviture of the cross section of the
street, and on six inches of concrete and backed up with same to
within six inches of top of curb. The concrete for this shall be
of same proportion and materials as that used for the concrete
foundation of the pavement.

CONCRETE FOUNDATION.

Upon the prepared sub-base shall be placed and thoroughly
tamped a five inch layer of Portland Cement concrete.

This concrete shall be composed of one (1) part Portland
Cement and nine (9) parts first calss pit gravel containing a proper
proportion of clean sharp rock sand and no gravel larger than two(2)
inch.

Separation of sand and gravel and recombination, will not
be insisted upon unless tests made on materials coming to the work
show an objectional disproportional of either element.

A barrel of Portland Cement will be considered as four
cubic feet. A standard bag will be considered as one cubic foot.

The approved pit gravel shall be measured in bottomless
boxes 6 feet long, four one-half feet wide and one foot high accura-
tely struck off. Three standard bags of cement being used to each
measure of gravel.

The work of measuring and mixing shall be done on a plat-
form of two inch planks of proper size, tight joint and
level. After the proper amount of cement shall have been evenly
spread upon the gravel the bottomless box shall be removed and the
mass thoroughly mixed by turning and re-turning with shovels.

The concrete shall be mixed at least four times. Two times
wet and two times dry.

After the mass has been mixed dry, water in sufficient
quantities shall be gradually added while the mass is being thorogh-
ly mixed. Care must be taken in the amount of water used in making
the concrete so that it is neither lacking in water to give its
proper setting nor too wet.

After the concrete has been properly made it shall be
placed by barrows or direct shovelling in a single layer five or six inches as
required thick and well tamped into place.

This concrete shall be allowed to set at least 4 days.