Dr Nikola is an occultist anti-hero seeking immortality and world domination. This is the second Dr Nikola story, also known as Dr Nikola Returns, which went through muliple printings from 1896. Guy Boothby was an Australia author published in the United Kingdom ahead of NSW Bookstall creating an Australian market for this this type of book.
The indicia for this issue is not recorded. The identified publisher might be an associated or parent company, rather than the specific listed publisher.