Except, it turned out, China Mobile has built towers everywhere in the country—towers, moreover, that put out the signal which allows my BlackBerry to work. I have owned one of these outlandish, life-changing, infuriatingly addictive CrackBerry devices for a year now; I had packed it when I was leaving New York; I had it in my hands at that very moment, and I was turning its knurled wheel and pressing its buttons idly, just wondering, wondering.

And yes, it worked. As I turned it on, it sprang effortlessly into cyber-connected life, and within a few moments of two-thumb typing, I had its tiny colored screen alive and performing a Google search for "hotels, Dunhuang, China." Moments later I was speaking to the receptionist in one of them, a young woman whom I remember most as having a delightfully smiling voice.

I was broken down, I told her, a little breathlessly. I was stranded. I was a hundred or so miles from the hotel, somewhere west of the Jiayuguan Fort. So I needed help. In fact, I needed cars. Two cars, one to rescue me and one to bring home the broken Volkswagen. And although my Chinese was execrable, my interpreter was in quiet hysterics, and my plaint most unusual, the receptionist—who when I finally met her turned out to be called Merry, a name I thought wonderfully appropriate—got it immediately. Hold on, she said cheerfully. Calm down. Yes, we can arrange that; wait in the back of the car; get some sleep; we'll be there in . . . let's see . . . five hours. Leave your flashing lights on.

Sure enough, a little before 3 a.m., out of the night came two sets of headlights. One belonged to a tow truck and the other to a giant Toyota Land Cruiser with two young men aboard, along with boxes of noodles and beer and a bowl of chicken soup. We turned around, set off—and were in the Dunhuang oasis by dawn. We probably felt, at that moment of arrival, no less astonished and delighted than did Aurel Stein, a little more than a century before.

This doughty, implacable, imperturbable, case-hardened explorer, already legendary at age forty-five and an acknowledged expert on the wild deserts of western China, had by the early 1900s become obsessed with one story: how Buddhism was transported from its birthplace high in the Himalayas of India, across the ranges and into the vast and protectively xenophobic empire of China. That it had been brought there was no doubt: The White Horse Temple, outside the eastern Chinese city of Luoyang, had been built by the emperor Ming in the first century a.d. and was an unequivocal celebration of the Noble Eightfold Path of Buddhism. But how had something so very Indian become, in short order, transported, transformed, and transmuted into something so very naturally Chinese? Aurel Stein, plodding patiently through the deserts just north of the mountain ranges, was determined to discover the answer.

His research, and that of other scholars in France and Germany, showed that it was all the work of a number of determined monks. Some were Indian, some Chinese, and in the first decades of the first millennium they carried the word of the Buddha, in oral teachings only, across the snowy passes between the two great empires and onto the trade route between central Asia and China that would in time become known as the Silk Road.