This is an account of Allan Sandage ’ s work on ( 1 ) The character of the expansion field .
For many years he has been the strongest defender of an expanding Universe .
He later explained the CMB dipole by a local velocity of 220 \pm 50 { km s } ^ { -1 } toward the Virgo cluster and by a bulk motion of the Local supercluster ( extending out to \sim 3500 { km s } ^ { -1 } ) of 450 - 500 { km s } ^ { -1 } toward an apex at l = 275 , b = 12 .
Allowing for these streaming velocities he found linear expansion to hold down to local scales ( \sim 300 { km s } ^ { -1 } ) .
( 2 ) The calibration of the Hubble constant .
Probing different methods he finally adopted – from Cepheid-calibrated SNe Ia and from independent RR Lyr-calibrated TRGBs – H _ { 0 } = 62.3 \pm 1.3 \pm 5.0 { km s } ^ { -1 } Mpc ^ { -1 } .