After working at the Royal Greenwich Observatory he graduated from King's College, London before taking a job in a London bank. In 1873 he returned to the Royal Observatory, taking a position as a spectroscopic assistant.
Part of his job involved photographing and measuring sunspots, and in doing so he observed that the solar latitudes at which sunspots occur varies in a regular way over the course of the 11 year cycle.
After studying the work of Gustav Spoerer, who had identified a period from 1400 to 1510 when sunspots had been rare ("the Spoerer Minimum"), he examined old records from the observatory's archives to determine whether there were other such periods. These studies led him in 1893 to announce the period that now bears his name.
He conducted many observations with the naked eye, as well as observations of Mars using marked circular disks, leading him to conclude that the canals that were then widely believed to be evidence of life on Mars were "simply the integration by the eye of minute details too small to be separately and distinctly defined."