It was the abolition of the African slave trade that became his primary motivation.

He also published a book in 1808 about the progress of the abolition of the slave trade.

He opposed the abolition of the slave trade in 1807.

This was followed up by the total abolition of the British slave trade in 1807.

He was an early advocate of the abolition of the slave trade.

However, those which survived found an opportunity with the abolition of the slave trade.

It did have one significant achievement, however, in the abolition of the slave trade in 1807.

Although not a Quaker, he grew up to be closely involved in a cause associated with them, the abolition of the slave trade.

They were especially pleased with his fight for the abolition of the slave trade.

Most recently his main focus has been on Cargo, a project about the abolition of the slave trade.