THE INDIA RUBBER WORLD 



[Febrvary 1, 1916. 



PLANTATION SMOKE HOUSE PRACTICE. 



RUBBER FOOTWEAR PRICE LISTS. 



THERE is a phenomenon in connection with plantation sheet 

 rubber known as "stretching rusty or resinous," according 

 to B. J. Eaton in "The Tropical .\griculturist" (November, 1915). 

 that brokers frequently attribute to excess resin in the particular 

 rubber. Although this condition probably has no effect on the 

 real quality of the rubber, it affects its market value and should 

 be remedied. 



The appearance which is usually produced when the dry rubber 

 is stretched or lightly scratched resembles powdered resin. This 

 phenomenon is due to a sweating or exudation of the serum 

 left in the rubber, which comes to the surface as the sheet of 

 rubber contracts on drying. If this is unable to drain off or if 

 it is not removed it evaporates and leaves a thin film on the sur- 

 face. This film is not obvious until the rubber is stretched or 

 scratched when it breaks up and on account of the reflection and 

 refraction of light caused by the small particles its appearance 

 is indicated by a deposit resembling powdered resin. 



An investigation has been made of surface slime formation on 

 slab rubber. The fresh coagulum from the ordinary pans, which 

 had been only rolled or pressed lightly and contained a large 

 proportion of residual serum, showed a large amount of this 

 deposit. An analysis of the slime after drying completely in a 

 desiccator yielded nitrogen corresponding to a total protein 

 content of over 60 per cent. The remainder was chiefly resin 

 and mineral salts. 



The remedy for this fault is simply after machining and 

 making the sheets to wash in one or two changes of water and 

 if necessary to scrub the surface slightly with a stiff brush before 

 placing them in the smoke house. 



SMOKE ROOM CONTROL. 

 Temperature— The: usual method of controlling the tempera- 

 ture in a smoke house is by means of a maximum and minimum 

 thermometer. It is preferable, however, to use an automatic 

 recording instrument to check the work of the operator. 



Dampness.— In the case of "sweating" of the rubber in the 

 smoke houses and the deposition of moisture on the interior of 

 the building, it has been found that outside smoking arrangements 

 were employed with a flue leading into the smoke room. As a 

 rule, exterior smoking arrangements are unsatisfactory. The 

 principle of smoking is slow combustion, producing a product 

 rich in antiseptic constituents; consequently to obtain a good 

 smoke the fuel must burn at a comparatively low temperature. 

 Many of the products of this slow combustion, although volatile, 

 are easily condensed, and with an exterior furnace and long flue, 

 these products condense in the flue or near the end entering the 

 smoke room, and the water vapor which passes through con- 

 denses in the smoke room itself, on the rubber and on the walls 

 and roof of the room and causes "sweating" or deposition of 



moisture. Where the fuel is burnt in the smoke house itself in 

 boxes or holes in the ground there is sufficient heat to drive the 



water vapor out and only the other products are left to diffuse 



into the rubber. 



One factor in connection with smoking which is frequently not 



realized is that the drying caused by the heat is far more effective 



as a preventive of mold than the actual smoke products, creosote, 



etc. 



It has been actually stated by scientific workers that where 



mold appears on smoked sheet the rubber could not have been 



properly smoked. This is entirely erroneous, as the common 



mildews will grow most readily on the best smoked sheet if 



given the prefer conditions of moisture. 



FOR a decade or more, previous to last year, the United States 

 Rubber Co. sent out its new price lists of footwear, its terms 

 to retailers and to jobbers, so that they got into the hands of the 

 wholesale trade all over the country on January 1. Last year, 

 because of the expressed desire of a majority of the wholesale 

 shoe dealers, the announcement was postponed to March 1. 

 This year the company reverted to its previous policy, and the 

 new price lists of footwear made in the several factories of the 

 company were so mailed that they reached the customers Janu- 

 ary 1. 



These new lists are practically the same in detail, as regards 

 prices, as those sent out March 1, 1915, the only changes, which 

 were few, being a \ariation of five cents or less in individual 

 lines. 



As has been the custom in most years the company offers an 

 extra discount of five |)cr cent, for early orders, thus practically 

 making prices that much less than those prevailing during the 

 last half of 1915. 



Other rubber footwear manufacturers, as in previous years, 

 were but a few days later than the United States Rubber Co. 

 in publishing prices. 



The Hood Rubber Co. in its price list varies in minor details, 

 some lines being slightly higher, others a few cents lower, but 

 on the whole it is much the same as that of the older company. 



The Beacon Falls Rubber Shoe Co. will issue a net price list, 

 instead of gross price list with discount, and here also prices are 

 nearly the same. 



The B. F. Goodrich Co. issues a wholesale price list of its 

 "Hipress" goods which varies somewhat from the prices of 

 patent pressure process goods manufactured by the United 

 States Rubber Co. In some instances the Akron prices are con- 

 siderably higher, while in others the variation is only two or 

 three cents, generally higher, but in a few instances lower. 



It is evident that when these prices were made it was on a 

 basis of cheaper cost than is possible at this writing. It seems as 

 if these prices must have been determined upon as early as De- 

 cember 1, or thereabouts, when crude rubber was quoted at be- 

 low the present prices. 



The increase in the cost of plantation and wild rubbers 

 would seem to justify an early revision of the price lists, and as 

 all these are "subject to change without notice" the wholesale 

 trade is placing orders to an extent unprecedented for so early in 

 the year. In fact, some manufacturers have already enough or- 

 ders for early delivery to keep their mills extremely busy for two 

 or three months, and some anxiety is expressed as to the possi- 

 bility of securing sufficient crude rubber to cover requirements. 



THE NEW TENNIS PRICES. 



On Friday, January 21, the United States Rubber Co. withdrew 

 its price list of sporting and outing shoes, which had been in 

 operation since September 1. A new list was sent out to reach 

 the wholesale trade by January 24. This list showed an advance 

 in practically all lines of rubber-soled canvas footwear, with the 

 single exception of basket-ball shoes. 



The general advance is about five per cent, though some lines, 

 mainly the low-priced ones, show a higher percentage. The 

 Admiral oxfords and bals, which were priced respectively at 

 $2.25 and $2.50 net. are now $2,40 and $2.65. Other lines show 

 an advance of from two cents to ten cents a pair, most of them 

 being either five or ten-cent advances over September prices. 



Should be on every rubber man's desk— Crude Rubber and 

 Compounding Ingredients; Rubber Machinery; Rubber Trade 

 Directory. 



NEW RESILIENT WHEEL WITH SOLID RUBBER TIRES. 



A western concern is manufacturing a new resilient motor 

 truck wheel to be used in connection with solid rubber tires. 

 The elastic mechanism is enclosed in the hub of the wheel, 

 which otherwise is of standard type and can be quickly at- 

 tached to any car. 



