July 1, 1921 



;Sf. 



THE INDIA RUBBER WORLD 



733 



longer service. They are sold in 9 to 15-inch lengths and pro- 

 tect the hands, wrists, and forearms of the workers using solu- 

 tions of acids and metallic salts and strong, alkaline cleansing 

 fluids in plating, galvanizing, and other metallic and chemical 



operations. 



MERCURV GLOVES 



Gloves for mercury-workers are made in standard sizes of 

 from 9 to IS-inch lengths of a special compound to resist the ac- 

 tion of mercury in a liquid or gaseous state. They are used 

 largely by smelters to protect their hands, wrists, and forearms 

 from absorption into the system of minute quantities of the 

 poisonous metal, which is vaporized from cinnabar and other 

 ores by roasting. Formerly, heavy buckskin gloves were used 

 affording poor protection to the workers. Rubber mercury gloves 

 are also used by v\-orkers in the amalgamation process of ex- 

 tracting gold and silver from ores, the mercury, or quicksilver 

 being used first to unite with the precious metals in the powdered 

 ore and, after the e.xcess mercury is pressed out, the remainder 

 being volatilized with heat. Mercury-workers' rubber gloves are 

 also much used by makers of thermometers, barometers, mer- 

 cury-vacuum pumps, and other scientific instruments. 



CYANIDE GLOVES 



Gloves for cyanide-workers are made in black or white, usually 

 net-lined for hard usage. The sizes range from 9 to 15 inches. 

 The stock is heavy and specially compounded to withstand the 

 "burning" action of strong caustic solutions used in metallurgical 

 operations. The gloves are used to protect the hands, wrists, and 



Testing Electricians' Rubber Gloves 



forearms of mine-workers conducting the cyanide treatment of 

 gold and silver ores, in which cyanide of potassium in solution is 

 the active agent in dissolving and recovering the metals when 

 crushing and mercury amalgamation cannot extract the greater 

 part of the gold and silver content of the ores. These gloves are 

 also used as a safeguard by workers in the supplemental treat- 

 ment of ore tailings with sulphuric and hydrocyanic acid solutions. 

 Cyanide gloves are also used in photography, electro-metallurgy, 

 in the laboratory and in gold extraction. 



SPRAYERS' GLOVES 



Gloves of the same kind as those used by cyanide-workers are 

 now much used by orchardists in spraying trees with liquid 

 hydrocyanic-acid gas, dilute carbolic acid, crude sulphuric acid, 

 and cyanide of potassium solution, lime and sulphur, Bordeaux 

 mixture, and other germicides, furmcides, and insecticides. 



ELECTRICIANS' GLOVES 

 ' Linemen and others employed in cleutrical industries use heavy 

 gloves made of pure gum, or a rubber compound that is nearly 

 perfect as an insulator. The lighter-weight, gloves are usually 

 tested for non-conductivity up to 4,000 volts, and the gloves used 



on high-tension circuits are much heavier and are tested to with- 

 stand 10,000 volts. These gloves come in black, white, and 

 maroon, in sizes from 9 to 11, short, medium, and long, some 

 with palms and fingers reinforced. They usually give way first 

 across the palms, due to repeated pulling on heavy wires. The 

 method of repair is practically the same as that used in mending 

 cement-workers' rubber gloves; and if a careful job is done, the 

 gloves can be made quite as safe and serviceable as new ones. 



Nevertheless in repairing linemen's gloves, great care should 

 be taken, as stocks that resist electricity are an absolute necessity. 

 If a repair man will insist on lead stock containing litharge or 

 white lead — not any metallic substance that is a conductor of 

 electricity — and a high quality of cement, he will be pretty safe 

 and can do excellent work. He should be careful of red stocks, 

 for example, as they may contain oxide of iron. At the same 

 time, the repair man should not g\iarantee any such work and 

 should insist that his repairs be tested, just as new electricians' 

 gloves arc tested. 



TESTING LINEMEN'S RUBBER GLOVES 



In repairing electric linemen's gloves repairmen should bear in 

 mind that the material used in mending must be fully as good 

 as in the glove itself and that 

 special care should be exercised to 

 obtain a uniform cure. Linemen's 

 gloves above all things must be 

 non-conductors of electricity. All 

 rubber gloves are good insulators, 

 but a lineman's glove must not 

 only be of pure compound, .038 to 

 .040-inch-thick but must also have 

 a guaranteed dielectic strength of 

 10,000 volts. Each glove is tested 

 for such resistance when bought, 

 and later tested periodically to in- 

 sure the safety of the wearers. 



The method of testing line- 

 men's gloves in America is simple 

 but efficient. The glove is placed 

 in a copper case open at top 

 and bottom, and with an opening 

 also at one side through which 

 the thumb projects. The glove 

 is then nearly filled with water. 

 Tlie holder and glove are next 

 immersed in an iron bucket filled 

 with water to within an inch of the top of the glove holder. An 

 electrode connected with a high-tension current is placed within 

 the water-filled glove, and the iron bucket is also put in the 

 electric circuit. The tests include voltages ranging from one 

 and one-quarter times the power strength of the lines on which 

 the men ordinarily work, to the maximum of 10 milliamperes 

 at 10,000 volts. If a glove fails to offer the proper resistance to 

 the current it is rejected as defective. 



In French tests on heavy electrical gloves the latter are some- 

 times filled with mercury and then immersed in a mercury-filled 

 vessel, the resistance being measured between the mercury in the 

 two containers. Another test is to place each glove filled with 

 sand in a sand-filled vessel, the sand being made a conductor with 

 a saturated solution of ammonium hydrochloride ; and making 

 voltage tests as with water or mercury. 



RUBBER MITTENS 



Mittens of pure gum, red, white and black, plain, or with a 

 forefinger as well as a thumb, are used in many of the trades. 

 Most mittens are of heavy stock and often reenforced on the 

 thumbs and palms where wear is greatest. Mittens usually come 

 in a single standard size, are short and long, and in three weights. 



Copper Glove Holders 



