AfcusT 1, 1916.] 



THE INDIA RUBBER WORLD 



597 



350 trays. Smoke, previously cooled, is passed through the cham- 

 ber from a smoke generator for about 20 minutes, after which 

 communication between the chamber and the chimney is closed, 

 and the passage of the smoke into the chamber continued for 

 about an hour and a half. The progress of the coagulation is 

 observed through a glass window; and the chamber is kept closed 

 for half an hour after the coagulum has shrunk away from the 

 sides of the trays. The smoke is then allowed to escape, the 

 chamber opened, the trays are allowed to stand for two hours, and 

 the serum is poured off. The coagulum is transferred to a large 

 tank of water, in which it is left over night, the sheets of rubber 

 are washed with changes of water, and each sheet is then ex- 

 posed to sunlight for one to two hours, after which it is lightly 

 pressed in an iron or wooden mold and allowed to dry in the 

 air for five or six days. [F. Ripeau. French patent Xo. 477,238, 

 June 5 (1914).] 



App.^r.mis for Vvlc.\xiz.\tiun' bv Ultra-Violet Rays. See 

 note preceding. [H. Olivier, l-'rench patent Xo. 477,204 (June 

 3,1914)1 



OTHER CHEMICAL PATENTS. 



THE UNITED STATES. 



l,189,5-)9. Birdil 





Carle 



Elli! 



Montcla 



J., assignor to Ellis-Foster Co. 

 189,550. Coating comoosition. Carleton Ellis, 



to Enis-F6ster Co. 

 187.8fi9. Method of making plastic compositions. Konstantin Ta 

 Moscow, Russia. 



imiTED KINGDOM. 



LABORATORY APPARATUS. 



hydrogen SULPHIDE GENERATOR FOR INDIVIDUAI, USE. 



WHEX small amounts of hydrogen sulphide are desired the 

 generator shown in the illustration will be found very 

 convenient. As described by H. A. Xoyes, the apparatus is es- 

 sentially two ordinary test tubes, one of which 

 T; li just slips inside the other. Blow a small hole in 



I I the bottom of the smaller tube, insert a stick of 



JHB. I ferrous sulphide, close the open end with a one- 



" holed rubber stopper that has been fitted with 



a delivery tube. 



To use : Fill the larger tube about one-third 

 full of dilute acid and slip the smaller tube 

 down into the acid. Gas is generated and con- 

 ducted directly to the solution to be tested. 

 When through using, the inner tube is quickly 

 raised, stopper removed and the delivery tube 

 and test tube washed out under the tap. This serves as a very 

 satisfactory apparatus for individual use for the generation of 

 small amounts of hydrogen sulphide. It is extremely simple and 

 can be kept "ever ready" in the test tube rack. 



A CRUCIBLE "FOBK." 

 This little device, credited to H. G. Parker, of William Jewell 



College, Liberty, Missouri, has proved very practical and con- 

 venient. It was designed for the use 

 of students, but may appeal to chemists 

 in general. The fork is made of stout 

 aluminum wire. The prongs of the 

 fork enclose slightly more than a semi- 

 circle and should be bent to fit the cru- 

 cible used. The space between the ends 

 of the prongs should be large enough 

 to pass around the crucible when sup- 

 ported on a tripod, but small enough 

 to prevent the crucible from slipping 

 out when the fork is lifted. When 



properly adjusted the crucible is held very securely. 



A HIGH TEMPERATURE BURNER. 



The Scimatco laboratory burner illustrated below produces a 

 short, wide flame that is uniformly hot, and the coolest part 

 of it is hotter than the hottest part of a Bunsen tlame. The 

 extremely high temperaturt 

 of the flame of this burner 

 is due to perfect mixture, 

 maximum speed and the pre- 

 venting of back-firing by the 

 special design of the burner. 

 1 he latter feature consists in 

 the use of a grid of pure 

 nickel H inch thick, placed 

 at the top of the tube. 



lor many purposes the 

 burner replaces the blast 

 lamp, with a saving of 98 

 per cent in gas and the elim- 

 ination of expense, and 

 noise of the blast. The non- 

 reducing fiame of the Sci- 

 matco burner is particularly 

 suited for heating platinum 

 ware, as it prolongs the life 

 of the metal tenfold over that possible with the ordinary blast 

 burner. [Scientific Materials Co., Pittsburgh, Pennsylvania.] 



SPECIFIC GRAVITY BALANCE. 



The illustration shows a very conveniently arranged triple- 

 beam balance for general chemical use, and for taking specific 

 gravities. Weighings are obtained by movement of the riders 

 , _ along the beams. These 



riders are easily handled 

 and quickly placed in 

 notches, but cannot be re- 

 moved from the beams. An 

 adjustable support is pro- 

 vided for holding a vessel 

 of water in the case of spe- 

 cific gravity weighings. The 

 three beams are placed in 

 the same horizontal plane. 

 Capacity of the middle beam 

 is 100 grams by 10 gram 

 divisions ; back beam, 10 grams by I gram divisions ; front beam, 

 100 centigrams by 1 centigram divisions. Total capacity, 111 

 grams ; sensibility, 1 centigram. [ Voland & Sons, New Rochelle, 

 New York.] 



VACUUM DESICCATOR. 



The "home-made" vacuum desiccator de- 

 vised by Dr. Percy A. Houseman, shown in 

 the illustration, has proved very practical in 

 drying materials in vacuo above room tem- 

 perature. The apparatus is made from a 

 percolator fitted with a desiccator lid. 



The temperature at which the sample is 

 dried may be regulated by varying the 

 height above the electric bulb of the glass 

 triangles attached to the tripod. 



Replete with information for rubber manu- 

 facturers—Mr. Pearson's "Crude Rubljcr and 

 Compounding Ingredients " 



LABORATORY APPARATUS PATENT. 



UNITED STATES. 

 190,085. Viscosity testing appar.m,.. Hans F. M.iucr. Cedar Rapit 



