POTTERY. 
54 
spout, if required, is put on and the vessel 
laid aside to be further dried and “ burnt” in 
the kiln. 
3. The Potter’s wheel. Both interesting 
and fascinating is the occupation of watching 
a potter at liis wheel. The rapidly revolving 
block of clay is gradually converted into some 
useful article in obedience to every touch of 
his skilled hands, widening, depressing 
lengthening, shaping all the time. How 
easily he seems to work ! 
Burning. Prepared by any of the foregoing 
methods the article has to be burnt in the 
flames of a kiln. 
The heat drives off the “combined” water, 
to which clay owes its plasticity, and a hard, 
though brittle, material is left. 
The brown colour changes to red during 
heating, owing to the organic colouring matter 
being volatilised, and the iron (principally 
ferric oxide) being left. (It is due to this 
same compound that we have the “red dirt” 
of many of our hills). The darker streaks, 
seen in some of the burnt articles and called 
“clinker burn,” are due to an excess of heat 
(owing probably to the partial formation of 
ferrous oxide.) 
Glazing. The porosity of these earthen- 
ware vessels allows water to slowly percolate 
through them and when it is desired to pre- 
vent this, a glaze is used. Tlie glaze usually 
selected and prepared locally is litharge or 
massicot. Before burning, the vessel is wet- 
ted, dampened, and the glaze powder dusted 
