“The maps of it are quite useless, compiled from hearsay of wandering Indian or Chinese merchants, I think. I had the most up-to-date ones I could get from the Survey of India. Got hold of old Jones, who was our mapping expert in Palestine; you remember him, Harry.
“He sent me the best he had before I went off, but he wrote to the effect that I would be wise not to rely too much on anything north of the Hami-Urumchi road, barring the triangulated peaks.
“If you look at that atlas on the table there you will see that there is a big stretch of nothingness northeast of Kashgaria labelled Gobi Desert. It is part of the Gobi. For over three hundred miles in every direction it’s got not a single name on it, not even a track. Northward there are two lakes shown with fifty miles of river leading nowhere; and, although I’ve not been there, I’m prepared to make a modest bet that they’re not within one hundred miles of their proper location, even if they do exist. North again of that is Chinese Mongolia, almost unknown even now, and very vaguely mapped.
“So that between known Kashgaria and Mongolia there’s a piece of country much bigger than England, almost unmapped, without even a known road in it. The southern edges of it are known to be desert; of the rest we know just nothing. And the northern side may be—as shown—some three hundred miles from the southern, or, on the other hand, it’s just as likely to be five hundred or six hundred miles away.
“You could hide a country almost as big as Wales in it and never know of its existence, even if it were full of high snow mountains. So you see, although my old namesake’s story may be the result of a fever-stricken imagination, it’s no ways impossible.
“Well, somehow, that country drew me more and more, but I saw that to try and explore it would require a good deal of preparation, and I had no idea of taking it on by myself if I could get another fellow or two to come along. So I decided to come back to India, and see if I could get hold of some one with globe-trotting tastes. I had you two in my mind’s eye, and then I found Forsyth, and later on heard that you’d gone home, Harry.
“I stayed on up there a while just to get a bit more local knowledge, and the last week I came across that coin, and the finding of that is what I call ‘twice’ in my deduction series.
“Some miles from the village there’s a bit of a rise where the sand-dunes on the desert’s edge are rather big. One in particular is noticeably high: it’s by a deserted building of sorts, quite a modern outfit, been abandoned perhaps twenty or fifty, at most a hundred, years. It bears northeast, and must be more or less the direction my great-great-uncle started from. I took rather a fancy to the place, and rode out there two or three times to study the country. A few extra feet elevation make a lot of difference in the desert.
“My men were accustomed to my going out there, and as a rule I took one or other to hold my horse while I did a bit of map-work, to try and get something more or less accurate.
“One particular day, the air being very clear—we’d had rain twice in the week, an uncommon phenomenon at that time of year—I thought I’d go and make a final visit to have a last check of the map.