US923195A - Construction of roadways, footways, and the like. - Google Patents

Description

R 923.195 .EX

UNITED STATES PATENT OFFICE.

GEORGE ARTHUR MITCHELL, ARTHUR JAMES MITCHELL, AND ERNEST EDWIN MITCHELL.

OF LONDON, ENGLAND, ASSIGNORS TO THE ROADAMANT COMPANY, LIMITED, OF LON- DON, ENGLAND.

CONSTRUCTION OF ROADWAYS, FOOTWAYS, AND THE LIKE.

Specification of Letters Patent.

Patented June 1, 1909 Application filed February 16, 1909. Serial No. 478,168.

To all whom it may concem:

Be it known that we, GEORGE ARTHUR MITCHELL, of 192 Barry Road, East Dulwich, London S. E., England, builder, Anrnnn JAMES MITCHELL, of The Willows, Station Road, Crayford, London, England, quantity-clerk, and Enxssr Enwnx' MITCHELL, of 80 Henslowe Road, East Dulwich, London, S. E., England, builder, have invented certain new and useful Improvements Relating to the Construction of Roadways, Footways, and the Like, of which the following is a specification.

This invention relates to roadways, footways, courtyards, tennis courts, stair heads, landings, and the like and has for object to provide a durable, dustless and non-slippery facing or covering capable of withstanding extremes of heat and cold.

In the specification of previous Letters Patent No. 876377 dated Janna 14, 1908 we described a method of producing a road or like surface of such a general nature by heating certain constituents therein specified together with soda and applying the mass in the plastic condition to form the surface of the road or the like.

As the result of extensive experimentation upon the composition of the prior patent we have found that it is possible to obtain a product which is superior to that of said patent in a marked and unexpected degree, by employing the materials and proportions following which must not be substantially departed from Fine hard stone, 0. g. finely broken granite--- 30. parts Asphalt 58. 75 Bitumen l. 25 Hydraulic cement, e, 9. Portland 7 4 Soda, (1'. e. ordinary washin soda, crystal- Chalk or other mineral carbonate and friable gritty material, e. g., cockle shell or breeze 2. 0 To which may be added, asbestos 1 The bitumen should be first heated in a caldron, the asphalt then added, and as soon as this has become thoroughly melted the broken granite or fine stone is introduced and intimately mixed with the molten mass. The cement, asbestos, soda, chalk and shell or breeze, previously well mixed, are now added and the mixture is well stirred, raised to boiling point and allowed to simcases also the Want stirred in WlGll the mass 15 thoroughly melted.

As above indicated other hard stone of the district, say flint, may be used instead of granite, and in place of chalk another mineral carbonate such as magnesian limestone or dolomite may be used. Moreover the asbestos may in some cases be safely omitted.

When the material has been laid in mastic form the soft surface is preferably sprinkled with sand, which is rubbed in, and this rubbing process incidentally removes any blowholes which may form on the surface.

What we claim and desire to secure by Letters Patent is 1. A covering for roadways or other surfaces comprising fine stone, asphalt, bitumen, hydraulic cement, soda, mineral carbonate and friable ritty material in approximately the relative proportions of 3000 parts of the first, 5875 parts of the second, 125 parts of the third, 740 parts of the fourth, 50 parts of the fifth and 200 parts together of the sixth and seventh, substantially as described.

2. A covering for roadways or other surfaces consisting of fine stone, asphalt bitumen, hydraulic cement, soda, asbestos, mineral carbonate and friable gritty material in approximately the relative proportions of 3000 parts of the first, 587 5 parts of the second, 125 parts of the third, 740 parts of the fourth, 50 parts of the fifth, 10 parts of the sixth and 200 parts to ether of the sevgnth and eighth, substantial y as described.

3. A covering for roadways or other sui faces, consisting of fine stone, as broken 3 granite, 3000 parts, asphalt 5875 parts, bitumen -parts, Portland cement, 740 parts,

examines signed our names in the presence of two sub- 10 scribing witnesses.

GEORGE ARTHUR MITCHELL. ARTHUR JAMES MITCHELL. ERNEST EDWIN MITCHELL.

Vitnesses FREDERICK VVILLIAM BEUER, ROBERT MILTON SPEARPOINT.