Identifying an author in the British and Foreign Evangelical Review

In Iain Murray's booklet Rest in God, he refers to an article entitled, "Literature on the Sabbath Question" in the British and Foreign Evangelical Review, vol. 15, no. 56, 1866. It is a review article of a book with the same title by Robert Cox. At the end of the essay, the initials "R. H." appear. Does anyone have any idea who this person might be? I think that it might be Dr Robert Howie of Glasgow, but I am not sure.
In 19th century examples like Dabney and Samuel Miller they usually identify things they wrote under pseudonyms etc. Maybe a biography of Howie would confirm?