Colonial era Colaba-Alibag MO, operational since 1841, contains valuable information on geomagnetic phenomena of different periodicities. First Indian director Nanabhoy Moos compiled Colaba data and interpreted them radically differently, echoing current understanding. Moos rejected terrestrial origins for magnetic storms and tried to bind together meteorological, seismological and geomagnetic realms. Colaba instruments have historical and scientific significance. Move to Alibag was incidental.