July 1, 1911.] 



THE INDIA RUBBER WORLD 



359 



LATERAL CONNECTION BETWEEN SYSTEMS OF 

 LACTIFEROUS TUBES. 



T^O THE Editor of The Indi.\ Rubber World. — Sir: I note 

 •^ that you have offered a cup as a prize for the best system 

 or method of tapping CastiUoa elastica. I am exceedingly inter- 

 ested, but for reasons which will be apparent further on, feel 

 debarred from competition. No such sense, however, restrains 

 me from calling the attention of planters to the following 

 method which at least has the merit of established practice in 

 certain details. It is really a combination of two methods, 

 in the first instance avoiding the continuous excision of bark, 

 and in the latter reducing the cost of the collection of latex. 

 The accompanying sketch will enable the reader to easily 

 grasp the details of this method. So far as known to me all 

 practical work done in Mexico up to date involves a more 

 or less continuous excision of bark. In Tobago, British West 



Harvey's System. 



A. — Permanent vertical channel. 

 B. — Permanent transverse channel. 

 C— Cup. 



ToB.\GO System. 



-A. — \'ertical channels renewed an- 

 nually. 



P>. — Transverse channels renewed 

 annually. 



C. — Apron for collecting latex. 



Indies, however, the writer was informed by Mr. Harry S. 

 Smith, a representative of the Trinidad government, that their 

 practice involved the use of a chisel and mallet. A series of per- 

 pendiucular cuts are made, as shown in the sketch, the late.x thus 

 dripping down the surface in an irregular manner and neces- 

 sitating the use of an adjustable apron at the base of the tree, 

 from the surface of which the latex was scraped off with spoons. 

 Upon inquiry Mr. Smith stated that several people were em- 

 ployed in the operation of tapping each tree, apparently a much 

 heavier tax upon extraction than with the Mexican method. 



.Since it seems to be a pretty well-established fact that wound 

 response, as occurring in the case of Hevea Bnisiliciisis, cannot 

 be hoped for with Caslilloa elastica, a continuous excision of 

 bark cannot be lightly regarded and the merit of the Tobago 

 method becomes apparent. It has occurred to me that the for- 

 mation of permanent channels and further excisions of bark by 

 combining the Tobago method of chisel cuts between the estab- 

 lished channels, offers a promising field for further testing of 

 this suggested method. 



A remarkable fact in connection with the Tobago method is 

 that a series of chisel cuts made, say, eight inches, one 

 above the other, and laterally, say, four inches apart, seems 

 to secure all the substantial flow, as upon essaying an intermedi- 

 ate series within a few minutes after completion of the initial 

 cuts referred to, scarcely any latex is secured, which might indi- 

 cate some lateral connection in the system of lactiferous tubes. 



It is hardly practicable to apply tlie above system to trees that 

 have become much scarred by previous tappings with resultant 

 excrescences of renewed bark. The method contemplates in its 

 application clean virgin trees, such as would be dealt with in the 

 first tapping year of a planting of Caslilloa elastica, and also a 

 careful marking out of the position of the permanent channels. 



J.\MES C. H.\RVEY. 

 Sanborn, Estado de Vera Cruz, June 1, 1911. 



[If Mr. Harvey's suggestion is as practical as it appears at 

 first blush, it will be of the greatest value. The apron around 

 the base of the tree has adways seemed a trifle cumbersome, 

 and slow and difficult to adjust. If, therefore, by a system of 

 permanent channels in the bark the latex can be led to cups 

 placed at the base of the tree it will be much simpler and far 

 more economical. The suggestion of possible lateral connection 

 between the lactiferous systems is in the line of valuable dis- 

 covery and should be thoroughly investigated. — The Editor.] 



ELASTIC PRODUCTS OF ANIMAL ORIGIN. 



A CCORDING to Revue de Chiinie, certain animal substances, 

 ^^ specially treated, arc capable of yielding an elastic product, 

 identical as to the purposes for which it can be used, with 

 ruliber. Of this character are the osseous or cartilaginous fish, 

 certain fresh and salt-water molluscs and even the membrane of 

 the small intestine of mammals. 



On boiling fish, the water in which it is boiled is found to 

 contain a large quantity of albuminous matter, about 5 per 

 cent, of the weight of the fish. After this albuminous matter, 

 which contains a large proportion of phosphorus, has been 

 precipitated with the aid of lactic or acetic acid, and separated 

 by filtration, the liquid is slowly evaporated; on the upper surface 

 a very thick skin will be formed. On removing, by agitation, all 

 the bodies of liquid in contact with the air, the latter will as- 

 sume a more and more solid consistency and is transformed into 

 a mass, displaying more cohesive than adhesive properties. 

 MXev having been subjected to a prolonged drying in a drying 

 stove, it is treated preservatively by an addition of 5 per cent, 

 of formaldehyde. There is thus obtained a characteristic sub- 

 stance that withstands traction and compression and can be 

 vulcanized by the familiar processes. By adding a suitable 

 quantity of sulphur, a product identical with ebonite is obtained. 

 It may be stated that this new product is not soluble in the 

 usual rubber solvents, such as sulphide of carbon, benzine, 

 petroleum, ether, turpentine, very strong alcohol, etc. It is not 

 a conductor of electricity. Its coloring substance is dissolved 

 in weak alcohol and by this means it can be bleached. 



The fish can be used industrially, as a whole. The precipitate 

 of albuminous substance separated in the first place, is very rich 

 in phosphorus and constitutes an alimentary product of great 

 value. The muscular tissue can be transformed into a substance 

 resembling ebonite by intense vulcanization. The intestines, 

 bowels, etc.. may be made into glue together with the bones, 

 scales and bony parts, after the lime has first been extracted 

 from them, by means of hydrochloric acid. In addition to being 

 usefid in the preparation of glue, these various parts may be 

 ust fully employed in the manufacture of fertilizer. 



Furthermore, the elastic product, made as we have described, 

 may be mixed with ordinary rubber in any proportion and the 

 mixture can be vulcanized with just as good results as the ma- 

 terials taken separately. 



The manager of a western automobile manufacturing plant 

 credits rubber tires with a record of 15,000 to 20,000 miles service 

 and questions whether any iron or steel tire has ever accom- 

 plished such a mileage over the same roads and at a much lower 

 rate of speed and with the same or a smaller load. 



