Hello, my name is Ben and it is my pleasure to assist you with your question today. The copyright in literary works expires 70 years after the end of the calendar year in which its author dies. Assuming you are referring to the author and poet Edward Thomas who died in 1917, the copyright of his works would have expired in 1987. As such all of his works would not be in the public domain and free to publish
The last sentence's meaning is unclear. His work is not in the public domain? So not free to publish?
Please let me know if this has answered your original question or if you need me to clarify anything else for you in relation to this? Thanks