The Necessity of Atheism by Percy Shelley is one of the best you will ever find. It is precise and straightforward. It’s a joy to read only comparable to reading Nietzche’s the Antichrist.
I am looking for work by abolitionist Garrison; a lecture by Ernestine Rose in defense of Atheism, and Stunton’s work on women’s rights.
If you have pdfs or epub copies of these works, please share. And that is all the fishing I am doing today.