82 PHILIPPINE RESINS, GUMS, AND OILS 



water to which petroleum has been added. The petroleum is 

 said to facilitate the removal of dirt and resin. After the 

 first boiling the gutta-percha is ground and boiled again with 

 water, the process being repeated several times. This method 

 apparently results in a high-grade product. 



Gutta-percha is now being grown successfully in plantations 

 in a number of tropical countries, but not in the Philippines. 

 According to Foxworthy : * 



Successful extraction of gutta from the leaves is done by the Dutch 

 and the cultural methods adopted in the plantation are devoted exclusively 

 to leaf production. * * * 



No great development of the gutta-percha industry in the 

 Philippine Islands can be expected until the trees are grown 

 in plantations. 



The most important use of gutta-percha is for the insulation 

 of submarine and underground electrical cables. It is also 

 utilized considerably in the manufacture of surgical appliances, 

 funnels, bottles, and other articles which come in frequent con- 

 tact with acids. For these purposes it is valuable on account 

 of the ease with which it can be sterilized and its resistance to 

 acids. A familiar form is as the outer covering of golf balls. 



Palaquium ahernianum is a tree reaching a height of about 

 40 meters and a diameter of 1.5 meters. The leaves are alter- 

 nate, pointed at both ends, wider toward the tip than near the 

 base, from 12 to 20 centimeters long, the lower surface velvety 

 and with a rusty color. The flowers occur singly or in groups 

 of two or three on wart-like growths on the stem. The fruits 

 are one-seeded, somewhat rounded, and about 2.5 centimeters 

 in diameter. 



This species is apparently confined to Mindanao. 



Genus PAYENA 

 PAYENA LEERII Kurz. (Fig. 29). 



GUTTA-PERCHA 



According to Heyne f this tree produces a very good grade 

 of gutta-percha. 



This species has been collected once in Mindanao and once 

 in Tawi-Tawi. 



* Foxworthy, F. W., Minor forest products and jungle produce. Gov- 

 ernment of British North Borneo, Department of Forestry Bulletin No. 1, 

 Part II (1916), page 45. 



t Heyne, K., De Nuttige Planten van Nederlandsch-Indie, Volume 4 

 (1917), page 12. 



