Before his success as a playwright, Bridie was a practicing physician. "Solid paper" could potentially be a misrecollection of a specific or report he authored during his career in medicine or his service in the Royal Army Medical Corps.

: Research into his plays like John Knox and The Queen’s Comedy .

A "solid paper" reference may relate to the physical format of his collected works. His plays, such as those in The Devil to Stage , are frequently published in durable or heavy-duty paper editions by the Association for Scottish Literary Studies . 2. Scholarly Papers & Theses

However, the phrase likely refers to one of the following contexts based on his body of work and historical records: 1. Hardback Publications

"Solid paper" does not appear to be a standard literary or technical term associated with , the pseudonym of the famous Scottish playwright and physician Osborne Henry Mavor .