The 'Petition' is the brief in support of law suit, requesting the Calcutta court to ban publication and distribution of the Quran, under strict Indian anti-defamation law.
If you ever read the Quran, you will understand why anti-defamation laws would apply.
The petition was such a thorough and accurate history of Islam coming into India, that it was preserved as a book.
You can read it for free and I advise everyone, even Muslims, to do just that.
Indian courts follow British common law, and so the Petition was originally written in English.