Gospel of the Comforter by Steele is a 36 chapter work on the Holy Spirit and different aspects of Him (1897).
The Carnal Mind by Harmon Allen Baldwin is a 30 chapter work on the carnal mind, defining terms, biblical view, what is evil, guilt, pollution, self-denial, oppositon to light, etc.
Devotional Thoughts by Aitken is many chapter devotional work on various Christian life issues and topics.
Robert Shaw’s short 1 chapter work on God and the Holy Trinity is an excellent collection of observations and verses that defend the Trinity.
Evangelical Tracts of J.C. Ryle wrote well over two hundred evangelical tracts, of which more than two million were circulated, and many were translated into foreign languages. Throughout his ministry, he remained one of the strongest defenders of the evangelical reformed faith within the Church of England. His faithful witness to the Gospel of Christ needs to be heard more than ever today. The following selection of tracts are classics of Gospel Truth that readers came to expect from all his writings. His tracts are.
Teasley Holy Spirit and Other Spirits is about the Holy Spirit’s effect on the believer as wells as how other spirits (demons) try to affect mankind with specific unholy spirits.
Anderson Silence of God theodicy is about when God is silent, the silence of God, which in theology it is theodicy. Why doesn’t God immediately vindicate his children.