Continuity mistake: The entries into Quartermain's journal are supposedly covering events during 1881 and 1882. The entries consist of a day and a date, but no month. Taken in order, they cannot fit into the 1881-1882 calendar. For example, the two entries immediately before the June eclipse can only be in August 1882.
Factual error: The date for the solar eclipse is given as Wednesday, June 2, 1882. There was a solar eclipse in Africa that year; however, the date was Wednesday, May 17, 1882.