The one-spouted lamp becomes common in Middle Bronze IIA as the four-spouted lamp of the previous period disappears. The form continues in the potter's repertoire from then on. Improvements in the lamp seem to be driven by safety and functional concerns. The round base becomes flatter so that the lamp will be less likely to spill hot oil. Eventually lamps develop a disk base (Iron IIC). The pinching of the spout becomes more pronounced and eventually closes forming an extended spout to hold a burning wick in place.