Complex sentence: At that time, a monthly fee of 30 shillings was required of diggers on Victorian goldfields, and regular raids were made by troops of police to apprehend those who had not paid their licence fee.
Split into simpler sentences: At that time, a monthly fee of 30 shillings was required of diggers on Victorian goldfields. This meant that regular raids were made by troops and police to apprehend those who had not paid their licence fee.