This “saucer type” of lamp consisted of pottery with indentations for the wick. This one could support 4 wicks and so give more light. It would however use up the oil proportionately as to the amount of lit wicks. The user with this lamp had options as to how much light he wanted to generate.
Apologies for the quality of this picture but I wanted to show this example of one of the earliest types to chronicle clay oil lamp development. This example dates to before 1000B.C. and was a feature in virtually every house or tent during this time.