- A Key to the Knowledge of Church History (Ancient)
- Historical Sketches, Volume I (of 3): The Turks in Their Relation to Europe; Marcus Tullius Cicero; Apollonius of Tyana; Primitive Christianity
- Life in the Roman World of Nero and St. Paul
- The Ancient Church: Its History, Doctrine, Worship, and Constitution
- The Basis of Early Christian Theism
- The Gospels in the Second Century: An Examination of the Critical Part of a Work Entitled 'Supernatural Religion'