December 1, 1 ( >1 4. 



THE INDIA RUBBER WORLD 



173 



THE GERMAN EMPIRE. 



PATENTS ISSUED iwith Dates of Validity). 



279,271, Class 30b (February 1, 1911). Apparatus for making rubber ob- 

 jects. Elizabeth Lambert, I enba in ti lssc, in, Berlin-Wilmers. 

 dorf. 



279,376. Class 7 1 a (January 31, 1914). Rubbei tin treads with applii 



poi tiom Muni, i and Agal ha Ri ich, Schilli tra e, 

 Northeim. 



279.483. Class 63c (November 23, 1913). Vcou tic indication <-i aii ■ cap 



ins from pneumatic tires. rlaghaii Sylvi tei Chri topherson, 

 < Idense, 1 lenmark. 



279.484, Class 63c (Novembei 3". I'M'). Pneumatic wheel tires or hose. 



I ard Breuer, Pilsen. 

 , I lass 63c (January 17, 1914). Pneumatii tires, in which the ail 



tube has a thickened portion, which automatically closes punc- 



tures. Carl Lepelmann, vor dem Harttor, 1.'. Geldi 

 14, I I lOd (Dei mil., i ., 1913) \dju table truss, with si 



continuation. Karl Willig, Siihl, fhuringen. 

 279,649, Class 39a (November 16, 1913). \1 ing machine, specially for 



rubber. Fritz Kempter, Heinestra e, 10, Stuttgart. 

 279,735, Class 30d (March 1.!. 1914). Vpplianci Eoi prevention and cure of 



ilat feet. Kmil Huber, I liseri .item. 

 279,780. Class 39b (Januar) 10, 1913). Process foi improving synthetic 



products resembling rubber. Badische \nilin-und Soda Fabrik, 



Ludwigshafen. 

 279,801, Class 63c (January 9, 1914). Rubbei tires with hollow chambers 



arranged one above another. Uberl Witzel, Ludwigsburg 

 279,835, (lass .Mb (January 28, 1913). Process for manufactun ol prod 



ucts resembling vulcanized rubber. Badische Anilin-und Soda 



1.1. . ik, Ludwigshafen. 

 279,980. (lass 63c (February Is, 1913), Process of manufacture of tires 

 ■ liscs arranged radially with respect to a ring. Divine Tire 



Co., I 'I. ,. \. V. 

 280,025, Class 63c (February Hi. 1914). Protecth ver fur treads of 



pneumatic tires. Wilhelm Dietz, Aeussere Sulzbacher Strasse, 34, 



Xui tiberg. 



TESTING OF RUBBER GLOVES. 



RUBBER MEN ATTEND THE FIRE ENGINEERS' CONVENTION. 



The convention of the [nternationa] Association of Fire 

 Engineers, held at New Orleans, Louisiana, October 20-23, 

 was attended by many representatives of the rubber compa- 

 nies, who enjoy 

 associate m e m - 

 bership in the 

 organization, as 

 well as by ac- 

 t i v e members. 

 Among these 

 r e p r e sentatives 

 were the follow- 

 ing : For the Bi- 

 Lateral Fire 

 Hose Co. — Clay 

 Bird, of Chi- 

 cago ; Dayton 

 Rubber Manu- 

 facturing Co. — 

 John A. M a c - 

 Millan, of Day- 

 ton, Ohio ; Eure- 

 ka Fire Hose Co. 

 — S. P. Blanck. 

 P. O. Herbert 

 and C. B. Payne, 

 of Atlanta, and 

 Thos. B. Gal- 

 braith, of N e w 



York; Fabric Fire Hose Co.— A. C. Hopper, of Dallas, Texas, 

 and J. J. Rafter, of Atlanta: Firestone Tire & Rubber Co.— Geo. 

 A. Talbot, of Akron: The B. F. Goodrich Co.— A. H. Leavitt, 

 Akron; Goodyear Tire and Rubber Co. — J. E. Davies, and F. H. 

 Sawyer, of Akron: Sewell Cushion Wheel Co. — E. H. Milliken, 

 Boston, and H. J. Sewell, Detroit. 



UNITED STATES IN THE MARKET FOR DIRIGIBLES. 



Announcement has been made that the United States Gov- 

 ernment is considering the purchase of four dirigible balloons 

 for military purposes and that it has in view arrangements to 

 assist manufacturers of this class of equipment. Several 

 firms have been organized in this country for the construc- 

 tion of dirigibles. 



IT is customary for electric light and power companies to 

 furnish rubber gloves to those oi theii employes who may 

 have occasion to work on high tension apparatus. Since it is 

 impossibli to deteel by visual examination very minute defi 

 such us inn holes, a high voltage test is necessary to insure that 

 the gloves worn by the men will not break down when » 



n "live" apparatus. A greal manj oi the central station 

 companies also test the gloves used by their men periodically so 

 .1- to insure thai no gloves will be in use which have been me- 

 chanically injured Since the user depend absolutely upon the 

 gloves for protection, it is obvious thai everj precaution should 

 be taken to insure thai this confidence is not misplaced. 



The most usual practice in testing gloves consists in filling 

 iii. [loves with water and then immersing them in a can 

 of water. I he electrodes are connected to the water in the glove 

 and the water in the can, the electric current being applied to 

 the electrodes and raised gradually at a uniform rate until the 

 test voltage is applied to the glove, which varies from 3,000 to 

 10,000 volts, depending upon the kind and quality of glove 

 and the service for which it is intended. The test volt- 

 ages employed vary from one and one-quarter to two times 

 the voltage oi the circuit upon which the gloves are to be 

 used. The time of application of the voltage varies from one 

 minute to five minutes. An ammeter is connected in the test 

 circuit and all gloves are rejected whose insulation resistance 

 is si i weak that the current flowing through the glove exceeds 

 10 milliamperes at 10,000 volts. It is obvious that while the 



current flowing 

 through the gli >ve 

 may not be suffi- 

 cient to cause a 

 puncture (a punc- 

 ture is simply the 

 result of suffi- 

 cient current 

 having flowed 

 through the 

 glove at a defect 

 to produce 

 enough heat to 

 cause destructive 

 defects still it 

 may be sufficient 

 to shock the user 

 without produc- 

 ing any visible 

 effect upon the 

 glove. Theoret- 

 ically, some cur- 

 rent flows 

 through the glove 

 in any case, its 

 value depending 

 simply upon the resistance of the glove. If the resistance is 

 sufficiently high the current is infinitesimally small, while if the 

 resistance is low the current becomes large and serious results 

 follow. Obviously then the amount of permissible current should 

 be limited, because a current which will produce a severe shock 

 to the wearer of the glove may produce no material defect in the 

 glove itself. The limit of 10 milliamperes has been established, 

 as this is sufficient to produce a distinct shock. While this cur- 

 rent in itself would not ordinarily injure a person, the muscular 

 reaction resulting from the shock might cause a man to fall from 

 a pole or ladder and thus injure him from the secondary cause. 

 The accompanying photograph of the testing equipment at the 

 Electrical Testing Laboratories, New York, shows the method 

 of suspending water-filled gloves in metal cans for test. 



Glove Testing Foi ii'ment of the Electrical Testing Laboratories, Xew York. 



