The potter's wheel was one of mankind's earliest inventions and has changed surprisingly little in the last 6,000 years. A potter's wheel id not one wheel but two.
Primitive potter's wheel were made of stone. A disc-shaped stone was notched in the center to fit over a pointed pivot in the center of the lower stone. A nudge of the potter's toe set the lower wheel in motion, which rotated in the upper wheel. The upper wheel was where the potter shaped his clay.
Before using the wheel, a potter must knead his clay to rid it of impurities and air He "wedges" it---slicing it in half and slamming the halves back together to force out air bubbles. When he feels the clay is ready, the potter places a container of water at his workbench ( to keep his fingers wet) and turns to his wheel.The potter next throws the ball of clay down on the upper wheel. Then he sets the wheel in motion and surrounds the clay with his hands, forcing it to the center of the wheel head. Now the potter must "master" the clay, making it responsive to his touch. He applies pressure at the base of the clay ball, causing it to rise up in a sort of rounded cone. Then he pressed the top of the clay with his tumbs or the palms of his hands. Repeating this three or four times increases the flexibility of the clay and increases its strength.
At this point the potter "opens up" the clay ball by pressin his thumbs into the center, gradually hollowing it out. Applying pressure with his fingers, he evens out the thickness of the cylinder walls. Finally he shapes the clay into a vase, a pitcher, or whatever he chooses.
As the terms force, master, and throw imply, clay is not always easy to work with. Often a partially formed object will disintigrate into a shapeless heap of clay---perhaps because a tiny stone was overlooked when the clay was worked. The potter must begin to knead the clay again. Or he may dislike the way a pot is forming and sweep it off the wheel in disgust.
Jeremiah 18 describes God as a potter having trouble at His wheel because His people refused to obey Him.
" I have but shadowed forth my intense longing to lose myself in the Eternal and become merely a lump of clay in the Potter's divine hands so that my service may become more certain because uninterrupted by the baser self in me." - Mohandas Gandhi
