Whittaker brightened up. 'It's a chance,' he said. 'Let's go over to the Admiralty.'
We got into two of the waiting motor-cars - all but Sir Walter, who went off to Scotland Yard - to 'mobilize MacGillivray', so he said. 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 manbe 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
(1)Place where there are several sets of stairs; one that matters distinguished by having thirty-nine steps.
(2)Full tide at 10.17 p.m. Leaving shore only possible at full tide.
(3)Steps not dock steps, and so place probably not harbour.
(4)No regular night steamer at 10.17. Means of transport must be tramp (unlikely), yacht, or fishing-boat.
There my reasoning stopped. I made another list, which I headed 'Guessed', but I was just as sure of the one as the other.
GUESSED
(1)Place not harbour but open coast.
(2)Boat small - trawler, yacht, or launch. (3) Place somewhere on East Coast between Cromer and Dover.
