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THE INDIA RUBBER WORLD 



[July 1, 1919. 



PRACTICAL ADVANTAGES OF RUBBER PAVEMENTS. 



The section in the old Kent road, after carrying for 295 days 

 some of the heaviest traffic in London, amounting to 90 tons 

 per square foot per hour for twenty-four hours, was not per- 

 ceptibly worn, whereas an adjacent 4-inch wood block lost half 

 an inch in thickness in the same time under the same load. 



So successful was this initial experiment in rubber street 

 paving in the open that in 1914 the Federated Malay States 

 Government subsidized the laying of rubber pavements in front 

 of its Information Agency Offices at 88 Cannon street, London, 

 E. C. This was done in anticipation of the Fourth International 

 Rubber Exhibition in London and to advertise the Federated 

 Malay States as a great plantation-rubbcr-producing country. 



It is claimed that the road foundations do not require to be 

 nearly so strong in the case of rubber roads as with ordinary 

 wood blocks. The reason is that the vibration of the heavy 

 traffic on the latter causes the concrete foundations to dis- 

 integrate, even if the thickness of the concrete is in excess of the 

 now frequently adopted twelve-inch standards. 



The fact that thinner foundations can be used with rubber 

 roads can be set against the extra cost of the rubber blocks, 

 though even then the costs will not be equal. But the life of 

 the rubber road may be expected to be so much greater as to 

 more than compensate for the extra cost, apart from the ad- 

 vantage of silence and the prevention of skidding and side- 

 slip of vehicles. 



The latter claim may at first sight appear a somewhat re- 

 markable one, but it is a fact that the rubber road sections that 

 have already been laid have proved to be most effective "non- 

 skids," notwithstanding the prediction that when wet it would 

 become very shppery. Even when covered with oil, or when 

 black-leaded, the rubber road does not appear to cause motor 

 vehicles to slip. This was hardly expected when the first sections 

 were laid down. In fact, so convinced were English insurance 

 experts that the risk of disaster through side-slip on rubber 

 roads was enormous that they quoted absolutely prohibitive rates 

 when one section was being laid down, and a guaranty had to 

 be given to the local authority. Now the premium is just the 

 same as would be the case for any other road ; in fact, it is no 

 longer necessary to insure. 



RUBBER ROADWAYS LIMITED. 

 In 1915 a company known as Rubber Roadways, Limited, was 

 formed under the auspices of the Rubber Growers' Association 

 of London, with a proposed capital of $150,000 for the purpose of 

 exploiting the Dessau patent on the basis of plantation companies 

 participating in the venture. It was proposed for them to furnish 

 annually without charge during five years one-fifth of one per 

 cent of their output, in addition to a like further quantity at 24 

 cents a pound. An aggregate output of 20,000 tons a year would 

 have been sufficient to supply 40 tons free and 40 tons at the 

 price named. This would have amounted at that time to a free 

 grant of 1,000 tons of plantation rubber and an additional 1,000 

 tons at the nominal price of 25 cents per pound. 



Owing to the war the project did not fully materialize and 

 the activities of the company ceased, but it is now proposed to 

 revive experiments and as a beginning 400 square yards or nearly 

 a quarter of a mile of rubber roading is to be laid on High 

 street in the Southwark Borough of London. The company is 

 to furnish the rubber blocks for the initial covering and subse- 

 quent repairs for a period of years while the borough is to under- 

 take the laying and maintenance. 



Meanwhile hardwood blocks have become practically unob- 

 tainable in England and are likely to be very expensive for 

 yeari to come. Experiments have been made to improve methods 

 of attachment and the block now being used is the invention 

 of George Anderson of the Leyland & Birmingham Rubber Co., 

 Limited. The method adopted is that of vulcanizing the rubber 

 cap onto a steel plate ; segments of that steel plate are cut and 



lugs, and it is proposed to lay the blocks 

 It crust of the road, embedding the lugs 



turned down to 

 directly on the 

 in that crust. 



While it is believed that this style of block and method of 

 attachment mark a considerable advance over anything previously 

 devised, it is not contended that it represents the ultimate in 

 methods of road paving. Suggestions for improvement are 

 plentiful and it is anticipated that methods will be found to 

 utilize the lower qualities of crude rubber as well as waste rubber 

 for this purpose. In this direction point the recent experiments 

 in Southwark Borough, London, where the paving blocks are 

 made wholly from reclaimed rubber vulcanized at high pres- 

 sure in iron molds. 



REMARKS ON "UNWOVEN RUBBERIZED FABRICS." 



Contributed. 



THE i-ACT that Mr. Respess contributes the result of his 

 experiments in a very interesting article in the June issue 

 of The India Rubber World tempts me to indulge in the fol- 

 lowing resume of the subject. Researches in the matter re- 

 sulted in the following conclusions : First, that the rubberizing 

 of unwoven fabrics is by no means new. 



GOODYEAR'S TISSUE. 



In 1853, Charles Goodyear ("Gum Elastic," by Charles Good- 

 year, 1853, Volume I, page 190) says: 



Tissue is formed of a layer of cotton wool which is sized before 

 it is coated with gum. The dissolved gum is combined with it by 

 the spreading machine which makes a complete admixture of the 

 two articles. The fibre of the cotton is not broken . . . and it 

 is therefore . . . when corded, stronger than woven fabrics 

 of the same weight. 



GOODYEAR'S VELLUM. 



This is made of a bat of cotton of about }i- to J/2-inch in 

 thickness. The gum is pressed into and intermixed with the 

 wadding at one operation of the spreading calenders, and like 

 other fibrous fabrics it is manufactured with great rapidity. 

 It is made inpervious to air and water with much less gum than 

 the woven fabrics. Besides, the yarn is not liable to peel off as 

 easily as it does in other fabrics. It is for most purposes the 

 cheapest as well as the best of the non-elastic fabrics and when 

 corded bids fair to supersede the coated cloths entirely for many 

 purposes, particularly . . for the heavier uses for india 



rubber canvas. It is made when desired in imitation of various 

 kinds of morocco, kid and buff leather, and of different thick- 

 nesses and degrees of strength according to the thickness of the 

 wadding. 



GOODYEAR'S CORDED FABRICS. 



Tissue and vellum are made very strong (and are torn with 

 difficulty) when corded with silk, thread, tissue or spun yarn, for 

 the same reason that muslins and other woven fabrics are 

 strengthened by being barred or corded with threads stronger 

 than those of which the cloth is made. 



The different fibrous fabrics, when corded in this manner are 

 even stronger than india rubber fabrics that are made of woven 

 cloths. The uses of these fabrics are the same as those of tissue, 

 vellum and vegetable leather, but on account of their great 

 strength are applicable to a great many purposes for which those 

 fabrics would not answer, such as . . . tarpaulins, coach cloths, 

 etc. 



As far back as 1825, Thomas Hancock patented a substitute 

 for leather which consisted in saturating and combining various 

 fibrous substances with a solution composed of caoutchouc, in 

 which he mentions the use of a layer or layers of carded 

 cotton. Incidentally in the same year he took out a patent 

 which covered the mixing or covering fibrous substances such 

 as hemp, flax, cotton, wool, etc., with the juice of a tree called 

 the "Hevaea." 



In 1854, James T. Stoneham secured an English patent which 

 covered the application of caoutchouc compounds in solution as 

 applied to any felted fibrous matter, the rubber being applied by 

 "forcing it into the material by pressure of rollers similar to 

 calender rollers." 



Coming down to more recent times the following is to be 

 noted : Clark's patent felt made from rubberized cotton fleece. 



