The material of all sidewalks, laid, constructed or repaired within the corporation limits shall be as follows: The material to be used in the construction of sidewalks in the City shall consist of flagstone, artificial stone or cement, and where flagstone is used the stone shall be sound and durable, not less than two and one-half inches thick; edges to be made square and smooth so all joints will fit closely together. The bed shall be prepared with gravel or cinder to a depth of from four to five inches, covered with a layer of sand from three to five inches deep, in which to imbed the stone; all of which shall be tamped until it is solid so that each stone shall have a firm bearing throughout and be even in height at the joints.
(1955 Code. §303.01)