Conversation so far:
Where did Lowell Thomas begin his career?
Lowell Thomas and cameraman Harry Chase first went to the Western Front, but the trenches had little to inspire the American public.
What year did Lowell Thomas go to the Western Front?
During his 1917 visits to the battlefields, Lowell Thomas learned that the British had named General Edmund H. H. Allenby, as their new commander in chief in Egypt.
What did Lowell Thomas do for General Allenby?
Lowell Thomas traveled to Palestine as an accredited war correspondent of the British Foreign Office, where he met T. E. Lawrence, a captain in the British Army stationed in Jerusalem.

Question: How long did this last?
Self-contained rewrite: How long did Lowell Thomas's meeting with T. E. Lawrence last?