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between 100 degrees F., and 150 degrees F. The exact temperature shall be such as will insure uniform distribution and shall be'designated by the Engineer. The exact amount to be applied will depend on the character of the surface and shall be sufficient to coat the surface thoroughly and �p uniformly without having any excess to form folds or to flow off the base. If deemed necessary; the �. engineer may require that the bash be lightly r sprinkled with water in advance of the application of the prime. 2. Double Surface Treatment The bituminous material shall be asphalt grade I, AC -15, or an asphalt material which has had specific approval. The cover material shall be State Road Specification Rock Grade 15, or approved slag material. The first application of bituminous material shall be from 0.18 to 0.25 gallons per sgare yard, and the second application of cover material to be from 0.22 to 0.25 cubic feet per square yard. Aggregate for 1st and 2nd course shall comply to D.O.T. Specifications for this type of surface. The surface to be covered shall be swept clean and free from sand, dirt, dust, and other deleterious material by means of mechanical road sweepers, hand brooms, and approved mechanical blowers, and shall be free from moisture. The existing seal coat must have an approximate twC week curing period before the application of the first bituminous coat. No bituminous material shall be applied when the temperature of the air is less than 50 degrees F., or when in the opinion of the engineer, the weather conditions or the conditions of the existing surface is unsuitable. The asphalt material grade AC -15 shall be applied at a temperature of between 275 degrees and 325 degrees F. The exact temperature shall be desig- nated by the engineer. Immediately following the' application of bituminous material the cover mate- rial shall be distributed unformly over the bitum- inous surface by means of approved mechanical spreaders or trucks. Iimnediately after each appli- cation of cover material, brooming by experienced and skilled workmen shall be done to secure a uniform distribution which will insure a smooth surface. Additional aggregate shall be placed by hand on any areas not properly covered. Immediately' after spreading and dragging the cover material the -entire surface shall be rolled with a three ton to -8-