 He found the sights of slavery offensive and when FitzRoy defended the practice by describing a visit to a slaveowner whose slaves replied "no" on being asked by their master if they wished to be freed, Darwin suggested that answers in such circumstances were worthless.Enraged that his word had been questioned, FitzRoy lost his temper and banned Darwin from his company.The officers had nicknamed such outbursts "hot coffee," and within hours FitzRoy apologised and asked Darwin to remain.