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THE INDIA RUBBER WORLD 



[May 1, 1912. 



country, and a recent consular report says that Germany now 

 exports practically none to America, its trade being entirely 

 destroyed by American competition. 



Notwithstanding its wide use, the manufacture is confined 

 to but few houses. There are now two houses in New York 

 and one in Boston which have succeeded in producing a really 

 effective and satisfactory article, and these supply the entire 

 demand. 



As might well be imagined, the exact composition of this ad- 

 hesive is a carefully guarded secret. Broadly stated, however, 

 it is a compound of gutta-percha and other guttas and balata, 

 the former giving adhesiveness and the latter strength. The 

 gums are thoroughly mixed, gently heated and kneaded to the 

 consistency of a somewhat thin dough, by being run through 

 and through heated cylinders, and then pressed out between pol- 

 ished steel calender rolls so adjusted as to give the resulting 

 sheet the desired thickness. This runs from one and one-half 

 thousandths, of an inch (.0015 in.) to four or five thousandths 

 o-f an inch (.004 to .005 in.). 



The material comes from this machine in a continuous sheet, 

 a yard wide, and this is suspended for a proper length of time, 

 to thoroughly season. It is then put up in the various forms 

 desired by the trade. One style of package is much the same 

 shape as a bolt of dress goods. The yard-wide tissue is folded 

 in yard lengths back and forth, one hundred yards in a pile, and 

 then each side of the pile is folded towards the middle, and one- 

 half folded over the other. In this form it is sold at about 65 

 to 75 cents a pound, according to quality. The various thick- 

 nesses run from four to twelve yards to the pound. Other forms 

 in which it is marketed are rolls, like ribbon, of any desired 

 width, according to the purpose for which it is to be used. 



One important use of this tissue is in the manufacture of the 

 backing cloth mentioned above. A sheet of this tissue and a 

 thickness of drilling, or cotton cloth, are run together, under 

 pressure, between heated calenders. This is sold to shoe manu- 

 facturers, who back up their light leather by hand. Other houses 

 make a business of backing leather or fine cloths for the shoe 

 trade, the work being done on machines which are not open to 

 the inspection of the public. 



New uses are constantly being found for this cement, its clean- 

 liness, convenience, pliability and absence of moisture being 

 properties which commend it to many mechanical trades. 



A NOVEL USE FOR RUBBER CEMENT. 



pRESENT-DAY illustrating has made the use of the air- 

 ^ brush almost universal among artists because of the extreme 

 delicacy of the effects produced and the facility with which it pro- 

 duces them. A novel use of rubber cement has been discovered 

 in connection with the use of this tool, which may be of interest 

 to the trade. 



The air-brush is a modification of the well-known principle of 

 the atomizer, adapted to throw a fine spray of thin ink as the 

 artist directs to produce the effect desired. A finer or coarser 

 line may be made by holding the tool nearer to or further from 

 the paper, and a tint can be spread over a large surface and 

 shaded, from the merest, lightest gray to the deepest black, by 

 proper manipulation and adjustment. 



After the outlines of a drawing have been made and properly 

 inked in, it is frequently desirable to put in the tints and shades 

 with the air-brush, and yet these shades must be kept from those 

 portions of the drawing which represent the high lights. 



Some artist discovered that rubber cement, thinned down with 

 benzine, would hold two pieces of paper together as would paste 

 or mucilage, yet these sheets could be easily separated when de- 

 sired, even after several hours' contact. This discovery i.' 

 now put to very practical use by many artists and draughtsmen. 



Upon the unfinished drawing is poured a small quantity of this 



thinned cement, which is then spread with the finger. Over this- 

 is pressed and smoothed down a piece of tracing paper, thus- 

 covering, but not hiding the drawing. Then, with a sharp knife, 

 skilfully used, sections of the tracing paper are cut around, and 

 these pieces raised and removed so as to expose those portions 

 which arc to be finished with the air-brush. Then the spraying 

 is done, without the danger of overlapping the lights, and with 

 an obvious saving of time and trouble. This work being done 

 in a satisfactory manner, the mask of tracing paper is easily 

 peeled off and the drawing finished up as desired. 



Of course, a fine film of rubber remains upon the face of the 

 drawing. This is easily and quickly removed by simply rubbing 

 with the finger, or with an ordinary sponge rubber eraser, the 

 cement being rubbed into little rolls or threads, and leaving on 

 the drawing no trace of the treatment to which it has been sub- 

 jected, in this somewhat mechanical manner, to secure an artistic 

 result. 



In this connection it might be well to state that where variation 

 of shade or tint is desired, as, for instance, a spot or line of high 

 light in the tint or shade, the rubber eraser, deftly used, brings 

 out the effect quickly and satisfactorily. 



The cement used for this purpose is common bicycle tire 

 cement, thinned down with benzine, to the consistency of cream 

 or syrup. We understand that a preparation of this kind — in 

 fact, this identical mixture — was for some time exploited under 

 a fanciful name by a couple of artists, who succeeded in working 

 up a fair demand for it, but who had too little of the commercial 

 temperament in their make-up to continue and expand the busi- 

 ness. 



A SAMPLE OF A RUBBER MAN'S ART. 



THE advertising manager of the Republic Rubber Co., Web 

 Brown, is also a cartoonist of some note. .A.t the recent 

 convention of fire chiefs of the United States and Canada he drew 

 a number of pictures of the leading men at that convention which 

 attracted a good deal of attention. We reproduce herewith his 

 picture entitled "A Night Alarm at Bradford. Pa.," which shows 



A NISHT ALARM AT BRADFORD PA 



the fire department of that city in active operation. The rings 

 that appear back of the moving machine would naturally be 

 taken for tires that had not been able to keep up the pace were 

 it not that there are five of them while the machine has only four 

 wheels. They are probably only punctures made in the at- 

 mosphere by the rapid movement of the engine. The usual 

 fire department mascot will be seen galloping swiftly in the 

 foreground. 



