Plot of tilt measured by a long-base water-tube tiltmeter near HVO. The data show clearly that the summit inflated during the summit eruption in Kilauea Iki in November-December 1959 and then plummeted during and for several months after the Kapoho eruption. This pattern, and the one shown by the events in 1961, is typical: inflation or no change during summit eruptions, and abrupt deflation during flank eruptions. However, the magnitude of the deflation in 1960 dwarfs anything since. This deflation, though striking to scientists, is not detectable without special equipment. A microradian is only one part per million. A tilt of one microradian is produced by putting a dime under one end of a 1-km-long bar. Not much! Simplified from Eaton (1962).