156 PHILIPPINE PALMS 
sap flow. The yield varies greatly, depending on climatic con- 
ditions, the age of the tree, and the length of time the sap has 
been running. According to Hines, the flow gradually dimin- 
ishes from 10 or 12 to 2 liters per day after two and one-half 
months. Gibbs,* however, reports a maximum of over 2 liters 
per day on two trees tapped under his directions. 
Ordinarily the sap is allowed to ferment, the product being 
known as tuba. This palm wine is a very popular drink in 
the Philippines and corresponds to the tiba of the coconut, 
buri, and nipa palms. Tuba is popularly supposed to have 
curative properties, especially for persons suffering from tu- 
berculosis. Fermentation commences in the bamboo tubes in 
which the sap is collected, and is usually well advanced when 
the product is gathered. 
In some regions much of the tuba gathered from the sugar 
palm is converted into vinegar of a good quality. Alcohol is 
distilled from the fermented tuba only to a very limited extent. 
Sugar is made in some parts of the Philippines by boiling the 
sweet, unfermented sap of this palm. The general practice is 
to use a new receiver (bamboo joint) for the sap each day, 
because old receivers would at once start fermentation. To 
prevent rapid fermentation a little crushed ginger or crushed 
chile-pepper fruit is sometimes added to the receiver.t In Java, 
for the same purpose, the bamboo joints are smoked before 
being used for collecting the sap. The general method of man- 
ufacturing sugar is to thicken the juice by boiling in an open 
kettle until the liquid is of such consistency that a drop of it 
will solidify when it falls on a cold surface. Sugar manufacture 
on a commercial scale has apparently never been attempted, and 
various authors who have investigated the sugar possibilities 
of this palm, have considered its commercial cultivation im- 
practicable. Both Barrett + and Hines ¢ give optimistic reports 
regarding the possible commercial utilization of this palm 
as a source of sugar; the former reporting an estimated annual 
yield of 20 tons of sugar per hectare, with from 150 to 200 trees, 
the latter that 20 tons of sugar per hectare would be the mini- 
mum yield with an average of 160 trees. It seems probable 
that these estimates were based on insufficient data, especially 

* Gibbs, H. D., The alcohol industry of the Philippine Islands, Philippine 
Journal of Science, Volume 6 (1911), Section A, pages 147 to 206. 
+ Barrett, O. W., The sugar palm. Philippine Agricultural Review, 
Volume 7 (1914), pages 216 to 221. 
+ Hines, C. W., Sugar-palm sap, Philippine Agricultural Review, Vol- 
ume 7 (1914), pages 222 to 228. 
