[Ormsby-Gore's] report ignored an important incident which reflects the political mood in Palestine at the time. This incident was a theatrical event, “The Girl of Adnan and the Fortitude of the Arabs,” which took place in Jerusalem on the nights of the eleventh and twelfth of April 1918 as part of the Al-Rashidiyyah Forum. Lights were focused on a large relief map of Palestine. Under the map the following verses were written:
Oh land of Palestine which was blessed
Oh auspicious land of the children of the Arab nation,
Oh God’s own beloved land, don’t lose hope.
I love only you.
We will redeem you with our souls
And travel the road of travail
Gathering light from Arab East and Arab West.
Until Palestine will shine,
Radiant as the sunrise.
Now, it is true that there was a smattering of specifically Palestinian Arab nationalism before 1920. However, the mainstream Arabs of Palestine supported a pan-Syrian nationalism, and Palestine was traditionally a part of southern Syria. Even the Mufti supported a Syrian Arab state that included Palestine. So while this event may have occurred, it is an overstatement to say that it was an "important incident."
Outside of this book, I cannot find a single reference to this event on the Internet, in English or in Arabic (assuming I am translating it right.) I think it is far more likely that this event, if it happened at all, was of minor significance and its importance is being pumped up now in order to strengthen the near-myth of Palestinian Arab nationalism.
(I would also love to know what the boundaries of "Palestine" were in this "large relief map." Certainly it was not congruent with British Mandate Palestine, so the map itself would be highly interesting - begging the question of why Palestinian Arabs are no longer interested in the portions of Palestine that lay beyond the Jordan.)
One would think that a history textbook would use facts that are easily verifiable. Terming this event an "important incident" when that incident is nearly impossible to corroborate seems to be more the domain of history researchers, not textbook publishers, and if they are going to assert this event they should point to a source.