  We have mapped the high-redshift (z = 0.546) cluster Cl 0016+16 with the Ryle
Telescope at 15 GHz. The Sunyaev-Zel'dovich decrement is clearly detected, and
resolved. We combine our data with an X-ray image from ROSAT, and a gas
temperature from ASCA to estimate the Hubble Constant H0 = 69 +21/-16 km/s/Mpc
for an Omega_M=1.0 cosmology or H0 = 84 +25/-19 km/s/Mpc for Omega_M=0.3 and
Omega_Lambda=0.7.
