Conversation so far:
What scientific research did Marie Stopes do at the University of Manchester?
During Marie Stopes's time at Manchester, she studied coal and coal balls and researched the collection of Glossopteris.
Was Marie Stopes' research on coal ever published?
Marie Stopes went to Japan and explored coal mines for fossilised plants. She published her Japanese experiences as a diary.
Did Marie Stopes prove the theory of Eduard Suess?
Fossils of plants from the Queen Maud Mountains provided evidence of Gondwana or Pangaea put forth by Eduard Suess, supported by Marie Stopes' research on coal.
Did Marie Stopes do any other research on coal besides Permian seed ferns?
During the First World War, Marie Stopes studied coal for the British government, which culminated in the writing of Monograph on the constitution of coal with R.V. Wheeler in 1918.

Question: What research did Stopes do in Japan?
Self-contained rewrite: What research did Marie Stopes do in Japan?