766 School Science and Mathematics

tank, which was circular, this is equivalent to saying that 7r==3 wasthe value used. But is this assumption justified? May it not be thatthe "molten sea" was elliptical, and the measurement from brim tobrim was that of a minor axis, or even a major axis? These alterna-tives seem to depend upon the use of three words, in the translations:round, circumference, and diameter. How are these defined in our dic-tionaires?

Round: One dictionary gives "... circular or curved". Anothersays: "having a curved outline or form, especially one like the arc of acircle or an ellipse." Still another uses the definition: "having such acontour that a section in some direction will be circular or approxi-mately so."

Circumference: "the line bounding a circle or other rounded sur-face . . . Circumference refers to the line bounding a circle or any ap-proximately circular or elliptical area," according to one dictionary.Another says: "... in general, periphery, circuit, or bound. Theboundary line of a circle, also of any plane figure that is bounded by acurved line."

Diameter: One dictionary says, "a line through the center of aplane figure, terminated at the boundary thereof." Another authoritysays "... measurement across, width or thickness of a thing."On the basis of the two verses, and the definitions in standard

references, is the case proven that the Hebrews used TT== 3? This writerbelieves the evidence is insufficient to establish the claim. It may betrue, but further evidence would be needed to establish the fact. Theuse of the word circumference may have led to misunderstanding.However, one more reference may be cited here: "Precisely, circum-ference designates either the line that describes a circle or an ellipse, orthe length of such a line; in extended use, however, it is applied to theline bounding any area thought of as circular or elliptical. ..."

Clearly, the "molten sea" might have been circular, but there isnothing to show that this was the case; as mentioned, it might havebeen elliptical, or even an irregular shape bounded by curved lines.Possibly some mathematical historian well grounded in Hebrewwould be able to help with a more exact translation.

AIR CUSHION BEATS GRAVITYA giant stool that walks on air will soon help to bring the weightlessness of

outer space down to earth.It is held slightly off the floor by compressed air tubes inside each leg, which

make movement almost friction-free. An "astronaut" will ride the stool in aspecial cradle which also floats on a film of air. The cradle will allow the riderto tumble in any direction.The stool will be used to study problems arising in free fall when moving men

and supplies between vehicles, doing maintenance and repair work, and usingtether lines between men and spacecraft. The device is being built for GeneralDynamics Corporation, San Diego.