  We present magnetization measurements on oriented powder of
ZnCu$_{3}$(OH)$_{6}$Cl$_{2}$ along and perpendicular to the orienting field. We
find a dramatic difference in the magnetization between the two directions. It
is biggest at low measurement fields $H$ or high temperatures. We show that the
difference at high temperatures must emerge from Ising-like exchange
anisotropy. This allows us to explain muon spin rotation data at $T\to 0$ in
terms of an exotic ferromagnetic ground state.
