334 



THE INDIA RUBBER WORLD 



[August i, 1907. 



to allow the contents to fall into the mill. A few moments only 

 are required for the mixing and the batch is ready for refining 

 or grinding. This is accomplished by drawing the mill rolls to- 

 gether as tight as possible. The workman operating from the 

 side of the rear or fast roll then takes off the compounded ma- 

 terial in form of a very thin sheet. This grinding answers the 

 double purpose of thoroughly incorporating with each other the 

 various ingredients of the compound and of refining, by crush- 

 ing, or bringing to view anything detrimental to it. 



The batch is now ready for the calender, where it is sheeted 

 to specified thicknesses, and cut to width required by that type 

 of insulating machine that places insulation material about the 

 wire in the form of strips. These passing with the wire between 

 grooved rollers, are made to conform to and adhere to it, the 

 surplus compound being trimmed away in the process. Where 

 insulation is thick enough to admit of it, it can be applied in one 

 or more coats. That is to say, a wire in passing once through 

 the machine may receive the insulation in two or more layers, 

 each difltering in character, cost and color. Machines of this 

 kind are also arranged to insulate more than one wire at a time, 

 which adds greatly to productive capacity. One great advan- 

 tage claimed for this method of applying insulation is that the 

 application of a second layer performs the office of automatic 

 repair upon any defects that may have developed in the first 

 layer. While a two or three layer cover is not necessarily free 

 from imperfections, it is clear that this method saves much 

 repairing. 



Another method of applying insulation is by means of the 

 tubing machine, which receives the compound direct from the 

 mixing mills. These machines are adapted to turn out insulation 

 of a certain weight, hence the elaborate equipment required by 

 a factory includes many sizes from the "pony" to the huge cable 

 maker. Each machine is also supplied with a number of dies to 

 meet requirements for different thickness of wall. 



A tubing machine in working order would have in front of it 

 a revolving table holding the coil of wire to be insulated. This 

 wire passes first through an automatic measurement register, and 

 thence through the tubing machine head. Here it receives the 

 insulation coat, and then passes over a long, narrow, talc-covered 

 table to the pan or drum on which it is wound. A firm stock 

 is wound on drums, a soft stock in pans, where each layer is cov- 

 ered with talc to prevent flattening during the curing process or 

 other injury. Thus prepared the wire is ready for vulcanization. 

 This is accomplished in the open heat, requiring from thirty min- 

 utes to several hours, with heat ranging from 250° F. upward. 



After curing, the wire with its covering of rubber compound, 

 now for the first time "insulated wire," is wound in coils con- 

 taining from a few hundred to several thousand feet. These are 

 assembled according to grade and size in huge metal tanks, 

 where they soak in water for twenty-four or more hours. The 

 electric voltage is then applied and the electric current soon 

 searches out any defects in the cover of the wire, breaking 

 through it with a slight explosion that causes bubbles to rise to 

 the surface of the water. Defects thus located are immediately 

 repaired and voltage applied again, and the process repeated if 

 necessary, until the insulation of the coil successfully sustains 

 the electrical test. 



[to be continued.] 



INSULATION NOTES. 



A SERIES of experiments by Teichmiiller and Ilumann, in 

 Germany, in relation to the heating of high tension cables 

 buried in earth, demonstrated the depths below the surface at 

 which the temperature of the earth is no longer influenced to 

 a considerable extent by variations of the temperature of the 

 atmosphere. 



A patent issued recently to George Kelly discloses the fact 

 that the discarded woven fabric chutes used for conveying con- 



densed zinc oxide can be made into an insulating material when 

 mixed with other ingredients. The discarded fabric is cut into 

 sheets and moistened by brushing with or dipping into a liquid 

 vulcanizing and binding composition composed of rubber, sulphur 

 and liquid glass (silicate of sodium). The resultant product 

 is described as a high-grade electric insulating board, slab, plate, 

 or the like that is thoroughly homogeneous. 



COTTON PRODUCERS AND CONSUMERS. 



THE president of the Southern Cotton Association, Mr. Harvie 

 Jordan, who is also editor of The Cotton Journal, published 

 at Atlanta, attended the fourth International Cotton Congress, 

 held in May in Vienna. The latter is an association primarily 

 of consumers, whereas the Southern Cotton Association is com- 

 posed of planters. Not the least interesting feature of the Vienna 

 congress was the emphasis placed upon the community of in- 

 terest between producer and consumer of cotton, instead of tlieir 

 being regarded, as in the past, as antagonistic. 



There is a widespread interest in Europe in the efforts being 

 made in various colonies to grow cotton on an extensive scale. 

 Mr. Harvie, after a study of the situation, writes in his 

 paper : "I do not think competition from abroad is likely to 

 ever seriously affect the demand for American cotton, even 

 though ultimately the most extravagant success should attend 

 the efforts to grow cotton in large quantities in foreign countries." 

 While he does not say so, it is evident that ]\Ir. Harvie 

 looks for such a continued growth of cotton consumption as 

 shall long tax the world's productive capacity in this commodity. 



We may suggest here that the mere fact that good cotton is 

 grown, and economically, in an African colony does not point to 

 an immediate great increase in the crop. For instance, the 

 English administrator of a certain colony estimated recently 

 that the territory in his charge, which has been proved to possess 

 soil and climate suited admirably to cotton, had an area suf- 

 ficient for producing as much cotton as is used in the United 

 Kingdom. But a friendly critic of this official, at his home, 

 called attention to the fact that the population of the colony was 

 inconsiderable, and that a long time would be required to get 

 the natives generally interested in the new crop. 



Still Mr. Harvie feels impelled to write : "We must no longer 

 be led astray by the false notion that the South is the only 

 country where cotton can be grown." And he utters a warning 

 against a continuance of the careless methods of marketing 

 American cotton abroad which leads to many complaints from 

 spinners. Neglect of this, he asserts, will result in "pushing the 

 production of cotton in other countries so as to become niort 

 independent of America if possible." 



The interest of this matter for the rubber trade is twofold. 

 Every addition to the world's cotton producing area serves as a 

 check to further advances in the price of cotton. Secondly, 

 Every addition to the world's cotton producing area serves as a 

 plantation and factory, increases the total efficiency, so to speak, 

 of each crop, and is equivalent to an increase of production. 



MONEY FOR UBERO CREDITORS. 



CREDITORS of The Consolidated Ubero Plantations Co. are 

 to receive a single dividend of 25 cents on the dollar, on 

 claims amounting to $58,701, under an authorization dated June 

 10, by Judge Dodge, in the United States circuit court in Boston. 

 This company was incorporated in Maine May 2, 1902, with a 

 large capitalization, and its affairs were so managed as to cause 

 one of its leading promoters, Borges, to be sent to jail. In the 

 summer of 1905 Jeremiah Smith, Jr., of the Boston bar, was ap- 

 pointed receiver for the company, in which capacity he was 

 lately authorized to pay the dividend mentioned. The history 

 of the company was stated at length in The India Rubber 

 World May i, 1905 (page 278). 



