Col. Fremont, in a letter written to his wife from Taos, the day after his arrival there in a famishing condition, and having lost one full third of his party by absolute starvation and freezing, mentions that at Pueblo he engaged as a guide, an old trapper of twenty-five years, experience, named "Bill Williams," and he frankly admits that the "error of his journey was committed in engaging this man." In narrating some of the incidents of this terribly disastrous journey, we shall use, of course, the language of those best qualified to depict its horrors, _i. e._, Col. Fremont, and Mr. Carvalho, a gentleman of Baltimore, who accompanied the expedition as daguerreotypist and artist. Col. Fremont, in his letter to his wife, treats of the subject generally, but when we quote from the narrative of Mr. Carvalho, we think our readers will admit that such a record of human suffering, and human endurance, added to such an exhibition of moral and physical courage, has never been paralleled. Col. Fremont writes, (speaking first of Williams the guide,) "He proved never to have in the least known, or entirely to have forgotten, the whole region of country through which we were to pass. We occupied more than half a month in making the journey of a few days, blundering a tortuous way through deep snow which already began to choke up the passes, for which we were obliged to waste time in searching. About the 11th December we found ourselves at the North of the Del Norte Cañon, where that river issues from the St. John's Mountain, one of the highest, most rugged and impracticable of all the Rocky Mountain ranges, inaccessible to trappers and hunters even in the summer time. "Across the point of this elevated range our guide conducted us, and having still great confidence in his knowledge, we pressed onwards with fatal resolution. Even along the river bottoms the snow was already belly deep for the mules, frequently snowing in the valley and almost constantly in the mountains. The cold was extraordinary; at the warmest hours of the day (between one and two) the thermometer (Fahrenheit) standing in the shade of only a tree trunk at zero; the day sunshiny, with a moderate breeze. We pressed up towards the summit, the snow deepening; and in four or five days reached the naked ridges which lie above the timbered country, and which form the dividing grounds between the waters of the Atlantic and Pacific oceans.