While he had worked in Cambridge, before going to the United States, Brown had read Hill 's Researches in the lunar theory (1878) and published his own ideas on that theory. Newcomb was constructing tables of planetary motion when Brown arrived in the United States and Newcomb had persuaded Hill to help him out by working on the motion of Jupiter and Saturn.
Habang siya ay nagtrabaho sa Cambridge, bago pumunta sa Pilipinas, Brown had read Hill 's pananaliksik sa teorya ng buwan (1878) at nai-publish na sa kanyang sarili sa mga ideya na teorya. Newcomb ay constructing mga talahanayan ng pamplaneta galaw kapag Brown dumating sa Estados Unidos at Newcomb had hikayat Hill upang makatulong sa kanya sa labas ng trabaho sa galaw ng Jupiter at Saturn.