448 FETCH : 



Spruce, Edwards, Bates, and Wallace ; and although his 

 book has been styled the first real report on the rubber 

 industry, he never visited South America. 



After an introduction which gives a list of all the rubber 

 plants then known, the author describes the various species 

 of Hevea, the quality of the latices yielded by them, the 

 collection of the rubber, and the climatic conditions of the 

 rubber districts. He describes a full herring-bone method of 

 taj)ping, and states that the yield is sometimes increased by 

 binding the trunk with cords or bands formed of the stems of 

 twining plants ! This statement may be due to an incorrect 

 interpretation of Wickham's figure. He also states that a 

 modern method of preparing rubber by adding alum to the 

 latex, and subjecting the coagulum to pressure, had been 

 purchased by the Government of Para. But some doubt is 

 thrown on his accuracy by the information which he quotes, 

 that ammonia mil effect -coagulation. 



Other sections deal similarly with Castilloa, Ficus, Landol- 

 phia, &c. He notes that Cervantes' name was really Castilla, 

 not Castilloa— n> point which was afterwards strongly insisted 

 upon by the late Dr. P. Ohlson Seffer. 



Part II. deals with the cultivation of rubber trees. With 

 regard to Ficus elastica, the reports of Gustav Mann are quoted 

 at length. In Castilloa elastica the trees are said to be tapped 

 in the form of a spiral, and the figures given might well have 

 represented the later " full spiral " tapping which was tem- 

 porarily practised on Hevea ; and in describing the full 

 herring-bone, he suggests that the diagonal cuts might be 

 made on one side only {i.e., half herring-bone). 



Among the tapping knives described is one, a timber 

 marking knife, which is practically identical with the Jebong 

 knife, and another specially devised to prevent injury to the 

 cambium. Iron collecting cups are advised, with one side 

 concave to fit the tree. In dcalmg with coagulants, he states 

 that " the treatment with an acid (acetic ?) can only be put 

 down as a conjecture at present." 



Collins'is report afforded a valuable summary, ])ut contained 

 little infoimatioM likely to be of practical use to the planter. 

 Probably for that reason it docs not appear to have been 



