The top of two iron bolts driven side by side and touching each other, situated at the intersection of Forest and Rose Streets and on the southeast corner of lot 5, block 68, New Whatcom, according to the plat of the town of New Whatcom, filed in the auditor’s office of the county of Whatcom, Washington, on August 31, 1883, which bolts shall be considered for all purposes of measurement in connection with grades and elevations in the city to be 105-42/100 feet above the base or datum plane, as is described in BMC 1.12.010, the bolts are driven six inches below the natural surface of the ground and also six inches below the top of the plug marking the south corner of the lot and block. [Code 1980 at § 13.04.020].