Spin echo measurements have been used to establish the way in
which the magnetic moments in GdAl
2 adjust themselves to the presence of dysprosium ions
introduced substitutionally into the lattice. The dysprosium
moments favour a (100) easy magnetisation direction in contrast to
the (100) of the GdAl
2 lattice. The results suggest that the gadolinium
moment directions change gradually from the (111) direction and a
model is examined for spherical volumes of gadolinium ions about
each dysprosium.