346 



THE INDIA RUBBER WORLD 



[April 1. 1916. 



CHEMICAL TREATMENT OF RUBBER. 



THE UNITED STATES. 



Restoring Rubber. United States patent No. 1,172,158. Fred- 

 erick Moench. The process consists in heating the vulcanized 

 old rubber waste in a closed retort out of contact with the air, 

 while enveloped with a plastic mixture containing linseed oil, 

 turpentine and an earthy material. 



Rubber Leather Sibstitute. United States patent No. 

 1,174,734. Benjamin Kepner. The process comprises treating a 

 fabric with a solution composed of glycerin, gelatin, an oil and 

 tannin, and thereafter drying the fabric in sunlight at a tem- 

 perature not over 120 degrees F. The softness and flexibiliyt of 

 the product is increased by treatment with water and applying 

 oil to the surface of the goods. 



VULCANIZABLE SUBSTITUTE FOR LEATHER AND RuBBER. — United 



States Patent No. 1,174,967, John Stewart Campbell. The proc- 

 ess consists in cooking a mixture of titiely divided leather and 

 animal fats or fatty oils with caustic alkali, adding fibrous ma- 

 terial, magnesia, a tilling material, and solution of elastic gum dur- 

 ing progress of the boiling of the mass. After removal from tht 

 boiler the mass is dried and milled on rollers, with the addi- 

 tion of a vulcanizing agent. The product is formed into sheets 

 and subjected to a vulcanizing operation. 



THE UNITED KINGDOM. 



Co.\GULATioN OF L.\TEX. 22,138 (1914), S. C. Davidson, Rub- 

 ber latex is coagulated by adding an "alkalized" cresol, cresylic 

 acid or higher tar acids, or other "alkalized" phenoloid, and an 

 aqueous solution of a thiosulphate, sulphite or other compound 

 capable of evolving sulphurous acid on treatment with acid or 

 acid substance, and finally coagulating by adding an acid or acid 

 substance to liberate the preservative substance in the phenoloid, 

 and also to liberate sulphurous acid. (Compare United States 

 patent No. 1,145,351 and 1,146,851, The India Rubber World, 

 September, 1915, page 648.) 



TRADE PUBLICATIONS ON LABORATORY APPA- 

 RATUS AND SUPPLIES. 



LABORATORY APPARATUS. 



AN IMPROVED CALORIMETER. 



/CALORIMETERS for industrial laboratory use arc not usually 

 ^^ adiabatic, permitting an appreciable loss or gain of heat be- 

 cause of relatively imperfect insulations, which fail to prevent 



t h e interchange 

 of outside and 

 inside tempera- 

 tures. The Riche 

 calorimeter is so 

 free from com- 

 plicated details 

 that it is said a 

 person with only 

 ordinary mechan- 

 ical knowledge of 

 the principles can 

 carry out per- 

 f e c t determina- 

 tions with it in 

 half the time re- 

 quired by other 

 calorimeters. 



This instru- 

 ment is encased 

 in a cork-lined 

 cabinet of wood, 

 and equipped 

 with electrical 

 means for igniting the material being tested. The special 

 feature which should be noted is that a glass vacuum cup is used 

 to contain the water and bomb. By this arrangement the entire 

 heat of combustion is confined for a period of at least one-half 

 hour. 



The bomb is a two-valve, porcelain-lined type, guaranteed for 

 3,000 determinations, but with proper care good for 8,000 or more 

 combustions, the two-valve arrangement allowing for carbon di- 

 oxide determinations. .\ny style of bomb, however, may be used 

 in this calorimeter. [Lenz & Naumann, Inc., New York City.] 



GENERAL Laboratory .Apparatus and Supplies. Lenz & 

 Naumann, Inc., New York City. This is a new well-indexed 

 catalog of 499 pages, in which all the well-known standard appa- 

 ratus, as well as many specialties are illustrated and described. 

 The lines carried include chemical, medical, surgical and physical 

 apparatus, glassware, specialties and chemicals. 



* * * 



ViTROSiL. The Thermal Syndicate, New York City. Pure 

 fused silica in numerous forms of tubes, plates, dishes, etc., de- 

 signed for laboratory purposes. 



Centrifuges. International Instrument Co., Cambridge, Masj. 

 An extensive line of centrifuges and other apparatus, including 

 Kjeldahl racks and bottle shakers for analytic work. 



Alundum Crucibles. Norton Co., Worcester, Massachusetts, 

 manufacturers of combustion boats, filtering covers and disks, 

 electric laboratory furnaces, etc. 



Optical Instruments for Inspection and Testing of Ma- 

 terials. Bausch & Lomb Optical Co., Rochester, New York. 

 Microscopes and accessories. 



Measurement of Conductivity of Electrolytes. Catalog 48. 

 The Leeds & Northrup Co., Philadelphia, Pennsylvania. 



* * * 



Btn^LETiN 12. Hoskins Manufacturing Co., Detroit, Michigan. 

 Electric furnaces, pyrometers and hot plates. 



device for reading burettes. 



A simple and effective device for reading 

 burettes is thus described by R. S. Poindexter : 



Take a piece of white rubber tubing 5 cm. 

 long, and of a diameter of about one-half that 

 of the burette. Slit it down one side, open it 

 out, and with a ruling pen and black ink make 

 a 1 mm. line down the center. 



When placed on the burette it will hold tight- 

 ly, and may be pushed up and down when the 

 reading is made. The refraction of the solution 

 in the burette causes a distinct pointer at the 

 ;he meniscus, making the reading very easy. 



NEW JERSEY ZINC CO.'S ANNOUNCEMENT. 



The New Jersey Zinc Co., New York City, announces the fol- 

 lowing prices on Florence brand, French process, oxide of zinc, 

 for shipment on contract, during the second three months of 

 1916: 



Carloads. Less Carloads. 



White Seal 25 cents 25H 



Green Seal 24,'.^ cents 



Red Seal 24 cents 



itnti 



The above prices are based upon shipments in barrels f. o. b. 

 shipping point, with freight allowance as heretofore on carload 

 lots only. The above prices effective from March 2, and subject 

 to change without notice. 



Contractors are requested to advise promptly the quantity de- 

 sired to be covered by contract. 



