DECE.MREK 1, 1914.] 



THE INDIA RUBBER WORLD 



141 



YOUNG'S GRAVITOMETER. 



Fig. 1. 



TIMS is a direct reading sp< ivity balance for solids, 



liquid . pigments or othi r finel erial insolubli 



in water. The instrument is so to eliminate all 



weighings and i al ulatii ms, oi 

 for the determination of a gravity. 



The operation of the balance for the determination of the 

 gravity of a solid is as follows: With the balance leveled by 



in e a n s oi the 

 thumb screw in 

 the ba s < . the 

 sample i o be 



pended on the 



point a n (1 the 



to the positii m 

 which will in- 

 fluence the 

 pointer b 

 ister at ' i in- 

 nim\ i on the 

 scale. ( Fig. 1.) 

 A beaker of 

 distilled water 

 is then placed 

 on the swing- 

 ing shelf which 

 is brought into 



position to allow the sample to be fully immersed, making sure 



that no air bubbles adhere to the sample. The pointer will then 



indicate the gravity of the sample to well within one per cent., 



whether the sample be heavier or lighter than water. (Fig. 2.) 

 In the determination of the gravity of liquids a sinker is used 



and the liquid gravity is read on a scale on the reverse side from 



the si ilid gra\ ity scale. 



For the determination of the gravity of pigments a receptacle 



is provided which is suspended in the place of the hook, and the 



operation is the same as with solids except for the use of a 



counterweight 

 The "Gravi- 



tometer," 



which is now 



on the market. 



is the inven- 

 tion of Philip 



E. Young, of 



the Acushnet 



Process Co., 



N T ew Berlfi.nl. 



Massa< husetts, 



and full par- 

 ticulars maj be 



obtained fri im 



him or fro m 



E i m e r & 



Amend. of 



New Yi .1 k 

 This balance 



is specially 



adapted for the 



rubber manufacturer, it being possible to determine accurately 



and quickly the gravities of all his products. 



GRINDER FOR STRENGTH TEST RUBBER SAMPLES. 



A .\n in the accompanying illustration has 



.imples of 

 , ubbi i "' ibsoluteli unifi on througl ample 



when the same are i strength. This 



machine « ned primaril) for the pur] rinding the 



Fie. 2. 



rubber backing off of samples of rubber lining to hose before 

 the lining was tested for breal ing strength. 



In preparing a sample of hose lining for test, a section of hose 

 several inches in length is -lilted along ils length, and the in- 

 terior lining with rubber backing is -tripped from the fabric. 

 This strip of rubber is cut to a uniform width of one inch 

 throughout a distance of three or four inches along the middle 

 of its length. The strip is then strapped closely to the platen 

 of the grinder, and is quickly and firmly placed in position by 

 the eccentric rolls shown in the cut. The strip is placed with the 

 smooth side to the platen, leaving uppermost the rough side 

 composed of the rubber backing to be ground ofl from the lining. 



By means of the longitudinal, vertical and cross adjustments 

 of the platen of this grinder, the sample may be quicklj ground 

 down to an absolutely uniform thickness throughout the entire 

 length of the test section. This machine requires less than J4 

 horse power for its operation, and is made up either as shown in 

 the cut. or fitted with directly connected motor drive. [Emerson 

 aratus Co., 251 Causeway street. Boston.] 



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

 Compounding Ingredients; Rubber Country' of the Amazon; 

 Rubber Trade Directory of the World. 



OTHER MACHINES OF THE MONTH. 



A new machine for wrapping strips of paper around finished 

 tires consist of a horizontal, hollow, annular shuttle into which 

 the paper strip is inserted in folds, thus eliminating the usual 



i The shuttle and tire revolve at right angles to each 

 Other, the strip being withdrawn from the interior of the shuttle 

 as it is wrapped around the tire. [( Kuent el assignor to The 

 Goodyear Tire & Rubber Co.. Akron, Ohio.] 



Another new machine automatically cuts a sheet of rubber 

 into strips with skived edges for making inner tubes. The calen- 

 dered sheet is carried by an endless belt forming a moving 

 table, under a series of circular cutters. These arc set at an 

 angle and slit the sheet into strips with skived edges, which 

 are afterward cemented together to form the tubes. [E. Xall 

 and W. C. Tyler, assignors to The Goodyear Tire & Rubber Co., 

 Akron. Ohio.] 



