  I propose that the phase transition in Bi2Sr2CaCu2O8 recently observed by by
Krishana et al [Science 277, 83 (1997)] is the development of a small d-xy
superconducting order parameter phased by pi/2 with respect to the principal
d-(x2-y2) one to produce a minimum energy gap delta. The violation of both
parity and time-reversal symmetry allows the development of a magnetic moment,
the key to explaining the experiment. The origin of this moment is a quantized
boundary current of I = 2 e delta / h at zero temperature.
