  In an exploratory study, using the tadpole improved clover Wilson quark
action on small, coarse and anisotropic lattices, the $\pi\pi$ scattering
length in the I=2 channel is calculated within quenched approximation. A new
method is proposed which enables us to make chiral extrapolation of our lattice
results without calculating the decay constant on the lattice. Finite volume
and finite lattice spacing errors are analyzed and the results are extrapolated
towards the infinite volume and continuum limit. Comparisons of our lattice
results with the new experiment and the results from Chiral Perturbation Theory
are made. Good agreements are found.
