Photograph of cryophorous and palm glass

N2L, cryophorous; palm glass

by placing one bulb in a liquid nitrogen bath, the green-yellow liquid in the other bulb (at room temperature) will freeze.

PIRA 4C31.10

Palm Glass:
this device is NOT to be used in liquid nitrogen. Cup one bulb in your hand to induce boiling in the other bulb.

PIRA 4C33.50