Conversation so far:
What political topics was Charles Bradlaugh interested in?
advocating birth control.
Why did he become an activist?
he was a convinced freethinker and in his free time he became a pamphleteer and writer about "secularist" ideas.
What years was he writing about his ideas?
In 1860 he became editor of the secularist newspaper, the National Reformer, and in 1866 co-founded the National Secular Society.
Did he write all the articles himself or were there other writers also?
Bradlaugh and Besant decided to republish the American Charles Knowlton's pamphlet advocating birth control.
Did he get in trouble with the authorities?
The two activists were both tried in 1877.
Were they found guilty?
They were sentenced to heavy fines and six months' imprisonment, but their conviction was overturned by the Court of Appeal.

Question: What is another topic besides birth control that he wrote about?
Self-contained rewrite: What is the other topic besides birth control that Charles Bradlaugh write about?