Twenty second- and third-grade children were tested on their ability to make judgements of certain area and volume equivalences. The children were then presented a conservation-of-liquid task. Of the 17 children who gave correct conservation responses, only two had solved the area and volume problems. Thus, contrary to what is suggested by learning theorist R. Gagne, knowledge of area and volume relationships is not a prerequisite for conservation of liquid. Gagne also suggested that acquisition of conservation of liquid in one type of container (e.g., rectangular) might precede conservation of liquid in another type of container (e.g., cylindrical), but no child was found who gave the correct response for rectangular containers who did not also give the correct response for cylindrical containers. The answers children give when asked to explain how they know that the quantity of liquid is the same after a transformation can be categorized as: (a) Identity ("It's the same water; nothing changed."); (b) Compensation ("It's fatter but lower."); and (c) Reversibility ("If you poured it back, it would be the same."). Identity was used by 78 percent of the seven-year-olds and 68 percent of the eight-year-olds, with 93 percent of the ten-year-olds using Compensation. These results are interpreted to mean that the initial acquisition of conservation of liquid is not dependent upon knowledge of geometry. (Author/PR)