With the one serious objection of slipperiness, compressed asphalte seems a most suitable material for the surface of a roadway, but that objection is of considerable weight when we reflect that the great object of roadways is that of “traffic,” and it is for that purpose they are constructed; still, in cities where a heavy _business_ traffic is going on, this class of roadway has so many advantages that where cheap horses are driven it might be used; where, however, valuable horses are used for pleasure driving, as in the west end of London and the corresponding better parts of cities, some other description of roadway should be maintained. Mastic asphalte will be described in the chapter on footpaths. _Specimen Specification for a Compressed Asphalte Roadway._ _Excavation and Concrete._--The excavation and concrete[98] foundation may be specified to be executed in a manner similar to that contained in the specimen specification for wood paving,[99] except of course that the excavation will be shallower in this case. _Asphalte._--The asphalte to be used shall be the pure unadulterated natural rock known as the Val de Travers, and be unmixed with any foreign or other matter whatever. The rock after being properly broken, shall be ground in a Carr’s disintegrator to a powder of such fineness, that not more than      per cent. shall be left on a sieve containing      meshes to the square inch and decrepitation by heat will not be accepted. This powder shall be heated to 240° F. or such other temperature as shall be found desirable, so as to eliminate all moisture, and carefully transported to the street in covered iron carts, in order that not more than 20° F. of heat shall be lost in transit. The powder must be spread upon the concrete    inches in thickness[100] and carefully raked so as to have regularity of depth and surface. _Ramming._--The powder must then be rammed with iron punners of not less weight than 10 lb. heated so as to prevent the adhesion of the asphalte. The ramming must be done lightly at first, so as to ensure equality of thickness, and afterwards augmented to heavy blows. Where the rammers are not available a T tool must be employed. To meet some of the objections to compressed asphalte as a material for roadways the “Imperishable Stone Paving Blocks” have been introduced in America; they consist of asphalte formed into rectangular blocks under pressure of about one ton to the square inch, these are laid close together without any grouting, and a pavement of this description is said to combine all the advantages of wood and asphalte, though sufficient time has not yet elapsed to prove this. In Salford, Manchester, etc., I believe “Woodward’s Patent Molten Ironstone Blocks” are used with some success where there is not any very exceptionally heavy traffic.