108 GIBBS. 



and the latter to some degree, do not appear to be used for this purpose 

 in India, although both occur there. 



The analj'ses of the saps of the Philippine palms show a variation 

 in different individuals, of the same species due to local conditions, and 

 also in the sap of the same palm at different periods of the sap flow. 

 Nevertheless, there is a remarkable uniformity in the composition of the 

 saps of the different species; in general, those of the best quality were 

 found to be practically of the same composition, about as follows : 



Density — - 







1.0700 



Solids 







17.5 per cent. 



Acidity 







Trace. 



Ash 







0.46 



Sucrose 







16.5 



Reducing sugars 





Trace. 



Nitrogenous 



compounds 



and 



undetermined 0.54 



Samples of about this character have been obtained from the nipa, 

 coconut, buri, and axenga pahns. 



The saps as they exude from the trees are practically neutral and 

 contain no sugar other than sucrose. The processes of inversion of the 

 sucrose and fermentation commence almost immediately. 



Considerable difficulty was experienced in preserving the samples for any length 

 of time before analysis. The preservatives tried were mercuric chloride, formal- 

 dehyde, chloroform, toluene, alcohol, lime, and sterilization by heat. Tlie last 

 is undesirable, since, in the cases investigated, it produces changes in the sap. 

 The nitrogenous bodies break down forming basic nitrogen compounds which 

 make the juice sti-ongly alkaline. Mercuric chloride is also undesirable for the 

 reason that it forms a heavy precipitate mth the nitrogenous compounds and 

 does not inhibit all other changes in the sap. Lime or calcium hydroxide is only 

 useful when the sap is utilized for the production of sugar. Alcohol is very 

 useful, the only change produced in the exuded sap being the precipitation of 

 nitrogenous matter as flocculent white substances which settle, leaving a clear, 

 supernatent liquid. For analytical purposes the alcohol does not interfere, since 

 the original composition of the sap can be calculated. Toluene, formaldehyde, 

 and chloroform, when put into the bottles and the sap allowed to drop from the 

 tree into the preservative, give satisfactory results, provided the bottles are 

 completely filled and then tightly stoppered. When access of air is possible, the 

 inversion of the sucrose is not stopped by the preservative. The inversion is too 

 rapid to be due to the acids formed, and results from an invertase which forms 

 from a zymogen. These and a number of other subjects are discussed under 

 their proper headings in the following pages. 



The uses to which the palm trees and their products are put by people 

 of all grades of civilization are almost innumerable. It is difficult to 

 overestimate their value to the native population and to tropical agri- 

 culturists. They furnish food, shelter, clothing, timber, fuel, building 

 materials, sticks, fencing, fiber, paper, starch, sugar, oil, wax, wine. 



