range, steadily increased in intensity until it became so severe as to endanger life, and day after day we plodded wearily on snowshoes ahead of our heavily loaded sledges, breaking a road in three feet of soft snow for our struggling, frost-whitened deer.  We made, on an average, about thirty miles a day; but our deer often came in at night completely exhausted, and the sharp ivory goads of our Tunguse drivers were red with frozen blood.  Sometimes we bivouacked at night in a wild mountain gorge and lighted up the snow-laden forest with the red glare of a mighty camp-fire; sometimes we shovelled the drifted snow out of one of the empty yurts, or earth-covered cabins, built by the government along the route to shelter its postilions, and took refuge therein from a howling blizzard.  Hardened as we were by two previous winters of arctic travel, and accustomed as we were to all the vicissitudes of northern life, the crossing of the Stanavoi range tried our powers of endurance to the uttermost.  For four successive days, near the summit of the pass on the western slope, mercury froze at noon. [Footnote:  We had only a mercurial thermometer, so that we did not know how much below -39 deg. the temperature was.] The faintest breath of air seared the face like a hot iron; beards became tangled masses of frosty wire; eyelids grew heavy with long snowy fringes which half obscured the sight; and only the most vigorous exercise would force the blood back into the benumbed extremities from which it was constantly being driven by the iron grasp of the cold.  Schwartz, the oldest member of our party, was brought into a Tunguse encampment one night in a state of unconsciousness that would soon have ended in death, and even our hardy native drivers came in with badly frozen hands and faces.  The temperature alone would have been sufficient evidence, if evidence were needed, that we were entering the coldest region on the globe—­the Siberian province of Yakutsk. [Footnote:  In some parts of this province the freezing point of mercury, or about forty degrees below zero Fahrenheit, is the average temperature of the three winter months, and eighty-five degrees below zero have sometimes been observed.]

In a monotonous routine of walking on snowshoes, riding on reindeer-sledges, camping in the open, or sleeping in smoky Tunguse tents, day after day and week after week passed, until at last we approached the valley of the Aldan—­one of the eastern tributaries of that great arctic river the Lena.  Climbing the last outlying ridge of the Stanavoi range, one dark, moonless evening in November, we found ourselves at the head of a wild ravine leading downward into an extensive open plain.  Away below and in front, outlined against the intense blackness of the hills beyond the valley, rose four or five columns of luminous mist, like pillars of fire in the wilderness of the Exodus.

“What are those?” I inquired of my Tunguse driver.

“Yakut,” was the brief reply.