up on the slope, we turned to the east to make a closer examination of the summits already mentioned.  I went in front, as usual, in the cheerful belief that we had a fairly level stretch before us, but I was far out in my calculation.  My ski began to slip along at a terrific speed, and it was advisable to put on the brake.  This was easily done as far as I was concerned, but with the dogs it was a different matter.  Nothing could stop them when they felt that the sledge was running by its own weight; they went in a wild gallop down the slope, the end of which could not at present be seen.  I suppose it will sound like a tall story, but it is a fact, nevertheless, that to our eyes the surface appeared to be horizontal all the time.  Snow, horizon and sky all ran together in a white chaos, in which all lines of demarcation were obliterated.

Fortunately nothing came of our expectation that the scamper would have a frightful ending in some insidious abyss.  It was stopped quite naturally by an opposing slope, which appeared to be as steep as the one we had just slid down.  If the pace had been rather too rapid before, there was now no ground of complaint on that score.  Step by step we crawled up to the top of the ridge; but the ground was carefully surveyed before we proceeded farther.

In the course of the afternoon we groped our way forward over a whole series of ridges and intervening depressions.  Although nothing could be seen, it was obvious enough that our surroundings were now of an entirely different character from anything we had previously been accustomed to.  The two mountain summits had disappeared in the fleecy mist, but the increasing unevenness of the ground showed that we were approaching them.  Meanwhile I considered it inadvisable to come to close quarters with them so long as we were unable to use our eyes, and, remembering what happens when the blind leads the blind, we camped.  For the first time during the trip I had a touch of snow-blindness that afternoon.  This troublesome and rightly dreaded complaint was a thing that we had hitherto succeeded in keeping off by a judicious use of our excellent snow-goggles.  Among my duties as forerunner was that of maintaining the direction, and this, at times, involved a very severe strain on the eyes.  In thick weather it is only too easy to yield to the temptation of throwing off the protective goggles, with the idea that one can see better without them.  Although I knew perfectly well what the consequence would be, I had that afternoon broken the commandment of prudence.  The trifling smart I felt in my eyes was cured by keeping the goggles on for a couple of hours after we were in the tent.  Like all other ills, snow-blindness may easily be dispelled by taking it in time.