Their behaviour in this respect closely resembles the balls of rapidly cooled, unannealed glass which are called Prince Rupert's drops.
Using an unannealed Swedish iron wire, he found that when H was gradually diminished from 0.04 to 0.00004 C.G.S.
A, B, C, D, E Unannealed Cobalt (S) A, D, E Nickel-Steel (W)..
A, C, D, E Unannealed Cobalt.
The permeability of cobalt, both annealed and unannealed, was always diminished at the low temperature.