  This article describes the Josephson tunneling from time-reversal
symmetry-breaking states and compares it with that from time-reversal invariant
states for both twinned and untwinned crystals and for both $c$-axis and
basal-plane currents, in a model for orthorhombic YBCO. A macroscopic
invariance group describing the superconducting state of a twinned crystal is
introduced and shown to provide a useful framework for the discussion of the
results for twinned crystals. In addition, a ring geometry, which allows
$s$-wave and $d_{x^2-y^2}$-wave superconductivity in a tetragonal
superconductor to be distinguished on the basis of symmetry arguments only, is
proposed and analyzed. Finally, an appendix gives details of the experimental
Josephson tunneling evidence for a superconducting state of orthorhombic
$ux^2+vy^2$ symmetry in YBCO.
