William Burt Pope’s Higher Catechism of Theology was published as an abbreviated version of his Compendium of Christian Theology in Q&A format. The Catechism contains some unique content and sheds light on the Compendium. You can read the entire Catechism in Logos Bible Software or PDF (scans from Fred Sanders).
The entire portion of the Catechism on the Christian Church is available on Holy Joys. It has been broken down into the following sections: