| Situation. | Description of Asphalte. | Years to be maintained by Contractor. | First Cost per Square Yard. | Agreed Cost of maintenance per Square Yard for the Contract Term. | Total Cost of Pavements during Contract Term per Square Yard. | Average Cost per Square Yard per Annum. | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| £ | s. | d. | £ | s. | d. | £ | s. | d. | ||||||||||||
| Cheapside and Poultry | Val de Travers (Compressed) | 17 | 0 | 18 | 0 | - | 2 | years free | - | 2 | 0 | 6 | 0 | 2 | 4 | ¹⁄₂ | ||||
| 15 | years at 1s. 6d. | = | £1 2s. 6d. | |||||||||||||||||
| Gracechurch Street | Ditto | 17 | 0 | 17 | 0 | - | 2 | years free | - | 1 | 12 | 0 | 0 | 10 | 1 | ¹⁄₂ | ||||
| 15 | years at 1s. | = | 15s. 0d. | |||||||||||||||||
| Finsbury Pavement | Ditto | 17 | 0 | 16 | 0 | - | 2 | years free | - | 1 | 7 | 3 | 0 | 1 | 7 | ¹⁄₄ | ||||
| 15 | years at 9d. | = | 11s. 3d. | |||||||||||||||||
| Moorgate Street | Ditto | 17 | 0 | 16 | 0 | - | 2 | years free | - | 1 | 7 | 3 | 0 | 1 | 7 | ¹⁄₄ | ||||
| 15 | years at 9d. | = | 11s. 3d. | |||||||||||||||||
| Ditto | Limmer (Mastic) | 17 | 0 | 16 | 0 | - | 2 | years free | - | 1 | 7 | 3 | 0 | 1 | 7 | ¹⁄₄ | ||||
| 15 | years at 9d. | = | 11s. 3d. | |||||||||||||||||
| Lombard Street | Ditto | 17 | 0 | 16 | 0 | - | 2 | years free | - | 1 | 7 | 3 | 0 | 1 | 7 | ¹⁄₄ | ||||
| 15 | years at 9d. | = | 11s. 3d. | |||||||||||||||||
| Cornhill | Ditto | 17 | 0 | 15 | 0 | - | 2 | years free | - | 1 | 6 | 3 | 0 | 1 | 6 | ¹⁄₂ | ||||
| 15 | years at 9d. | = | 11s. 3d. | |||||||||||||||||
| Mincing Lane | Ditto | 17 | 0 | 12 | 0 | - | 2 | years free | - | 1 | 3 | 3 | 0 | 1 | 4 | ¹⁄₂ | ||||
| 15 | years at 9d. | = | 11s. 3d. | |||||||||||||||||
The cost of foundations is included in this table, but their thickness is not mentioned; the excavation was done for the contractors.
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.