60 ^^6 Philippine Journal of Science ms 



wheels. These are usually disks of wood about 50 to 75 centi- 

 meters in diameter and 8 to 10 centimeters thick. The wheel 

 is given several revolutions by the feet of the potter and thus 

 acquires sufficient inertia to continue in motion for perhaps 

 thirty seconds. Most of the operators are skillful in the use of 

 these wheels, and much of the ware possesses consideiable 

 beauty. The molding of some of the articles is completed on 

 the wheel, but the rice bowls are afterward beaten with a flat 

 wooden paddle. This is done to increase the density for the 

 prevention of leakage and to produce walls as thin as is con- 

 sistent with the necessary strength. I have often seen these 

 pots with walls less than 0.5 centimeter in thickness, and so 

 uniform that the eye could detect no variation. 



When the molding is completed, the pottery is allowed to dry 

 in the shade for several weeks and is then burned by one of 

 two methods: 



1. A kiln is employed. There are several types. The com- 

 monest is long and horizontal and somewhat cylindrical in shape. 

 Wood is the common fuel. As a rule, high temperatures are 

 not obtained in this type of kiln; because of imperfect construc- 

 tion and the quantity of fuel used. However, in some of them 

 the temperature often exceeds 1,200° C. 



2. Much of the pottery, especially the rice bowls, is burned 

 without the use of a kiln. The ware is piled on the ground, 

 even in the street, and is covered with straw, pieces of bamboo, 

 rubbish, and the like. After the fuel is fired, it is allowed to 

 bum slowly until all is consumed. The condition of the ware 

 is observed from time to time through small holes in the straw, 

 and when it has reached a dull red heat, the burning is con- 

 sidered finished. The ash and partly burned fuel are gradually 

 removed, and finally the ware is completely uncovered and 

 allowed to cool. This whole operation usually does not require 

 more than an hour or two. 



It is largely imperfect burning that has held back the develop- 

 ment of Philippine pottery and has prevented a really well- 

 developed technic (in other respects) from producing ware of 

 excellent quality. From tests made in this laboratory, it is 

 apparent that the raw materials used in the district are of 

 satisfactory quality.^ Experiments have also shown that the 

 proportions in which the two substances are mixed are right 

 and that the methods of molding and drying certain kinds of 



'See data for clay No. 2, Witt, J. C, This Journal, Sec. A (1916), 11, 

 203. 



