Complex sentence: Emigration from England was at a peak, with over 350,000 people leaving that year, and Brown who at the time considered himself "very hard up and a little mad" was thinking of starting over in India with his new family.
Split into simpler sentences: Emigration from England was at a peak, with over 350,000 people leaving that year. Brown, who at the time considered himself "very hard up and a little mad", was himself thinking of starting over in India with his new family.