On the 28th of April [1875] I led a party up the mountain for the purpose of making a survey of the summit with reference to the location of the Geodetic monument.  On the 30th, accompanied by Jerome Fay, I made another ascent to make some barometrical observations, the day intervening between the two ascents being devoted to establishing a camp on the extreme edge of the timberline.  Here, on our red trachyte bed, we obtained two hours of shallow sleep broken for occasional glimpses of the keen, starry night.  At two o’clock we rose, breakfasted on a warmed tin-cupful of coffee and a piece of frozen venison broiled on the coals, and started for the summit.  Up to this time there was nothing in sight that betokened the approach of a storm; but on gaining the summit, we saw toward Lassen’s Butte hundreds of square miles of white cumuli boiling dreamily in the sunshine far beneath us, and causing no alarm.

The slight weariness of the ascent was soon rested away, and our glorious morning in the sky promised nothing but enjoyment.  At 9 a.m. the dry thermometer stood at 34 degrees in the shade and rose steadily until at 1 p.m. it stood at 50 degrees, probably influenced somewhat by radiation from the sun-warmed cliffs.  A common bumblebee, not at all benumbed, zigzagged vigorously about our heads for a few moments, as if unconscious of the fact that the nearest honey flower was a mile beneath him.

In the mean time clouds were growing down in Shasta Valley—­massive swelling cumuli, displaying delicious tones of purple and gray in the hollows of their sun-beaten bosses.  Extending gradually southward around on both sides of Shasta, these at length united with the older field towards Lassen’s Butte, thus encircling Mount Shasta in one continuous cloud zone.  Rhett and Klamath Lakes were eclipsed beneath clouds scarcely less brilliant than their own silvery disks.  The Modoc Lava Beds, many a snow-laden peak far north in Oregon, the Scott and Trinity and Siskiyou Mountains, the peaks of the Sierra, the blue Coast Range, Shasta Valley, the dark forests filling the valley of the Sacramento, all in turn were obscured or buried, leaving the lofty cone on which we stood solitary in the sunshine between two skies—­a sky of spotless blue above, a sky of glittering cloud beneath.  The creative sun shone glorious on the vast expanse of cloudland; hill and dale, mountain and valley springing into existence responsive to his rays and steadily developing in beauty and individuality.  One huge mountain-cone of cloud, corresponding to Mount Shasta in these newborn cloud ranges, rose close alongside with a visible motion, its firm, polished bosses seeming so near and substantial that we almost fancied that we might leap down upon them from where we stood and make our way to the lowlands.  No hint was given, by anything in their appearance, of the fleeting character of these most sublime and beautiful cloud mountains.  On the contrary they impressed one as being lasting additions to the landscape.