Timetipping
by Jack Dann
People, animals (or at least parts of them), and a reluctant wandering Jew are tossed
back and forth through alternate realities at various times.
Nothing was for certain, anything could change (depending on your point of view), and
almost anything could happen, especially to forgetful old men who often found themselves
in the wrong century rather than on the wrong street.
“Timetipping” by Jack Dann, in Epoch, edited by Roger
Elwood and Robert Silverberg (Berkley Putnam, November 1975).