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besides laying the foundation to a systematized study of Castilla and 

 Manihot rubbers. Considerable time was taken up in organizing the 

 work, and in equipping and arranging the laboratories. These 

 consist of a chemical laboratory, fully equipped with all necessary 

 apparatus and re-agents for analytic and experimental work ; a 

 plant physiological laboratory supplied with ordinary instruments 

 and microscopes ; a bacteriological department with all the para- 

 phernalia pertaining thereto, incubators, sterilizers, microtomes 

 and microscopes ; a rubber experiment department with various 

 appliances; a shop for making models and repairing instruments; 

 a library with reference books, literature on chemistry, tropical 

 agriculture, entomology, botany, coffee, and rubber, about forty 

 periodicals, and some 4,000 pamphlets on agricultural and related 

 subjects. 



Our first work was to take a survey of conditions on the 

 rubber plantation. Detailed observations were made of the rubber 

 over the entire estate. These data were copied on cards such as 

 intimated above. Maps were made showing the condition of the 

 rubber on different areas and from different points of view. 

 Suggestions were made as to treatment of the rubber stand. 

 A drainage system was partly worked out. 30,000 trees were 

 measured to ascertain the average girth and height of trees of 

 various ages. Observations on branching, leaf- formation, root- 

 development and light requirements were made, A complete 

 working plan for 30 years was formulated and submitted to the 

 managing director. Insect and fungus diseases were studied and 

 remedies tried. Means for preventing forest fires in the rubber 

 were suggested. 



A number of well-developed young rubber trees were selected 

 in the field and transplanted to the experimental grounds, which 

 had been opened. Here seeds of different Castilla varieties have 

 been sown. Cearaand other rubber producing trees and vines have 

 been planted. It is intended to get a complete collection of the 

 world's rubber and gutta percha plants. Castilla seeds have been 

 sown under varying conditions of soil to ascertain the difference 

 in development. Manuring experiments have been commenced. 

 Influence of catch crops is being studied. Observations are made 

 as to the best method of weeding, and the result of this as shown 

 in the progress of the rubber trees. Pruning and transplanting 

 experiments are going on, as well as experiments in grafting and 

 hybridizing. 



In the course of the plant physiological work experiments on 

 transpiration have been commenced ; the temperature of the tree 

 and of the latex in the tree is ascertained under different weather 

 conditions ; the effect of wounding is studied ; root and bark 

 pressure is experimented upon ; relation of leaf-fall to latex is one 

 subject of investigation ; several other lines of inquiry have been 

 entered upon, and numerous new problems will be studied in the 

 future. 



The bacteriology of latex and crude rubber is not entirely 

 unknown, and we have ascertained some very interesting facts. 

 Before these are published, however, the flora of the crude rubber 



