Reaching Abdullah’s camp at Abu Markha in Wadi Ais on 15 March, Lawrence delivered letters from Feisal explaining the situation in Medina and pressing the urgent need to block the railway; then succumbed to the bout of dysentery and malaria that had begun during his journey from Wejh. Lying incapacitated for days, he began to think out a new strategy for the Arab campaign.

“I had now been eight days lying in this remote tent … The fever passed: my dysentery ceased; and with restored strength the present again
became actual to me … So I hurried into line my shadowy principles, to have them once precise before my power to evoke them faded.

“It seemed to me proven that our rebellion had an unassailable base, guarded not only from attack, but from the fear of attack. It had a sophisticated alien enemy, disposed as an army of occupation in an area greater than could be dominated effectively from fortified posts. It had a friendly population, of which some two in the hundred were active, and the rest quietly sympathetic to the point of not betraying the movements of the minority. The active rebels had the virtues of secrecy and self-control, and the qualities of speed, endurance and independence of arteries of supply. They had technical equipment enough to paralyse the enemy’s communications … Final victory seemed certain, if the war lasted long enough for us to work it out.”

Events of 22 March 1917 as recounted by T. E. Lawrence in Seven
Pillars of Wisdom (1926).

“I should have written before but have been ill. However things are quite alright now …

“Please see Sidi Feisul for me and tell him I have not been able to do my job here because I have been ill. I hope to go down to the railway tomorrow for a preliminary reconnaissance and after that will be able to say what can be done, but in any case I will stay here a bit as it is most important that the Turks should not be able to concentrate much of their Medina force at El-Ula against him, and I am afraid if I do not stay here not much will be done.

“Please beg him not to remain in Wejh unless it is absolutely necessary. The effect both on Arabs and Turks of knowing him to be near the line would be very great…”

(Letter to an unnamed British officer written on 22 March 1917,
reproduced from Lawrence of Arabia: The Selected Letters edited by Malcolm Brown.)