We marched through empty corridors and big bare chambers where the charwomen were busy, till we reached a little room lined with books and maps. A resident clerk was unearthed, who presently fetched from the library the Admiralty Tide Tables. I sat at the desk and the others stood round, for somehow or other I had got charge of this expedition.
It was no good. There were hundreds of entries, and so far as I could see 10.17 might cover fifty places. We had to find some way of narrowing the possibilities.
I took my head in my hands and thought. There must be some way of reading this riddle. What did Scudder mean by steps? I thought of dock steps, but if he had meant that I didn’t think he would have mentioned the number. It must be some place where there were several staircases, and one marked out from the others by having thirty-nine steps.
Then I had a sudden thought, and hunted up all the steamer sailings. There was no boat which left for the Continent at 10.17 p.m.
Why was high tide so important? If it was a harbour it must be some little place where the tide mattered, or else it was a heavy-draught boat. But there was no regular steamer sailing at that hour, and somehow I didn’t think they would travel by a big boat from a regular harbour. So it must be some little harbour where the tide was important, or perhaps no harbour at all.
But if it was a little port I couldn’t see what the steps signified. There were no sets of staircases on any harbour that I had ever seen. It must be some place which a particular staircase identified, and where the tide was full at 10.17. On the whole it seemed to me that the place must be a bit of open coast. But the staircases kept puzzling me.
Then I went back to wider considerations. Whereabouts would a man be likely to leave for Germany, a man in a hurry, who wanted a speedy and a secret passage? Not from any of the big harbours. And not from the Channel or the West Coast or Scotland, for, remember, he was starting from London. I measured the distance on the map, and tried to put myself in the enemy’s shoes. I should try for Ostend or Antwerp or Rotterdam, and I should sail from somewhere on the East Coast between Cromer and Dover.
All this was very loose guessing, and I don’t pretend it was ingenious or scientific. I wasn’t any kind of Sherlock Holmes. But I have always fancied I had a kind of instinct about questions like this. I don’t know if I can explain myself, but I used to use my brains as far as they went, and after they came to a blank wall I guessed, and I usually found my guesses pretty right.
So I set out all my conclusions on a bit of Admiralty paper. They ran like this:
FAIRLY CERTAIN.