glass sphere

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Artificial oviposition substrates were thus constructed with glass spheres in order to test the behavioural activity of grapevine berry extracts.
The unevenness in the packing of the glass spheres cannot really be eliminated completely.
An experimental investigation of the explosions of 2 in. diameter glass spheres under high internal pressure has been made.
Ideally, in analogy with the explosion case, the external pressure should be reasonably close to the crushing pressure of the glasssphere.
The later implosion times are probably the result of a slower breaking process because of the smaller pressure differential across the glasssphere.
The glasssphere has shattered though it still maintains a spherical shape and the sphere interior is completely masked by the glass fragments.
The unsatisfactory nature of the shattering process was felt to be largely due to insufficient external pressure on the glasssphere.
A portion of the 4 in. pipe which initially held the glasssphere appears at the top of each picture.
Often used by monks to assist in illuminating manuscripts, these were primitive plano-convex lenses initially made by cutting a glasssphere in half.
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