466 Philippine Journal of Science 1919 
drug stores, 81 alcohol distilleries, 17 repacking establishments, 
and a few other industries the operation of which depends en- 
tirely on the solution of the bottle problem. In view of the 
above considerations, we undertook this investigation in order 
to determine the suitability of Philippine materials for glass 
making. 
Technically speaking, there are two general classes of glass 
recognized ; namely, lime glass and lead glass. Lime glass is the 
material most commonly used for making the cheaper articles, 
such as ordinary bottles, demijohns, glass jars, drinking glasses, 
lamp chimneys, etc.; while lead glass is a more expensive product 
and is used chiefly in the manufacture of cut glassware and for 
optical purposes. The principal raw materials used in the man- 
ufacture of lime glass are lime, silica, and alkali. 
LIME 
Coralline and crystalline limestones of good quality occur 
throughout the Philippine Islands,’ but the deposits most avail- 
able to Manila are those of Montalban, Binangonan, and Taya- 
bas. Both the Montalban and the Binangonan deposits are 
within the boundaries of Rizal Province; the limestone is of Mio- 
cene formation and is hard, crystalline, and of uniform chemical 
composition. 
Montalban is located about 30 kilometers from Manila, on a 
line of the Manila Railroad. Binangonan is situated about 35 
kilometers from Manila, with water transportation facilities via 
Pasig River and Laguna de Bay. 
The Tayabas deposit is a metamorphosed coralline limestone 
and is located at Palsabangan, a barrio on the railroad and be- 
tween the towns of Pagbilao and Malicboy. It is estimated that 
limestone may be obtained from any of these places at from 5 
to 8 pesos? per metric ton, including cost of quarrying and 
transportation to Manila. 
The Bureau of Science in its experimental kiln has manufac- 
e tured from Montalban, Binangonan, Cebu, and Tayabas lime- 
stones over 100 tons of excellent lime, suitable for use in sugar 
centrals and in other industries: and there is no reason why 
these limestones cannot be used for glass making. 
In this connection it would be of interest to note the composi- 
*Cox, A. J., Philip. Journ. Sci. § A 4 (1909) 211; Cox, Reibling, and 
Reyes, Philip. Journ. Sci. § A 7 (1912) 332. 
?One peso Philippine currency equals 50 cents United States currency. 
