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doubted, since we could not satisfactorily pick our personnel and would have to hire unknown packers. Furthermore, the summit passes cannot usually be crossed by animals in June, when we would want to start work, and could get to the job readily from this side.

Acknowledgment.-I desire to place on record my appreciation of the interest taken in the work by the men engaged in it, with particular reference to Forest Rangers Roy Boothe and Frank Price and Assistant Ranger Mark Cathey. The task of overseeing the packing of powder, steel, supplies, etc., over difficult mountain trails, and of handling men, the best of whom grow sick and tired of the isolation and monotony of camp fifty to seventy miles from civilization, is no small one and requires lots of patience and tact. I am glad to say that the work was so handled that many of the men who worked on the job this summer, and who are experienced, have asked to be considered for employment next

Respect fully submitted,


Forest Supervisor Northfork, California, November 22, 1915.


REPORT ON JOHN MUIR TRAIL WORK, SEQUOIA NATIONAL FOREST The route of the trail within the Sequoia National Forest was not definitely determined as early as in the Sierra National Forest, but, in the short period remaining after the final determination was made and before the close of the field season, good progress was made. The following expenditures were made for trail work within the Sequoia National Forest from the appropriation for the John Muir Trail: Wages

. $ 650.50 Subsistence supplies

209.47 Other supplies and equipment.

281.50 Freight, express and hauling.



$1,245.89 Approximately six miles of the hardest portion of the trail is completed, and a route between Kern and Kings rivers is opened. A portion of the trail at the head of Shepherd's Creek was completed with cooperative funds (not from John Muir Trail appropriation) at an expense of $200.00. This makes the total cost of the trail $1,445.89. Of the $1,245.89 from the John Muir Trail appropriation, $76.60 was expended for camp equipment and tools, and $1,169.29 for actual trail construction. With the additional $200.00 co-operative funds, the average cost per mile for the six miles, exclusive of camp equipment, was $228.21.

Ranger Parkinson, who was directly in charge of the work, reported on October 8:

"Saddle horses may pass from Center Basin to Tyndall Creek at the present time, but additional work will be done

of storm a temporary break in the clouds showed Lassen in an active state on the nineteenth. The eruption during the night of May 20 resulted in the flood which swept down Hat Creek on the mo

of May 21. The first telegraphed reports regarding this eruption told of molten lava flowing down the mountain sides and of streams of mud ejected from the crater itself, but the fact is now well established that the matter actually ejected from the crater consisted largely of rocks and ashes and of very hot steam.

This eruption was markedly different from preceding eruptions in that the column of steam and ash, instead of being projected upward as usual, was directed obliquely down the slope of the mountain. Evidently the throat of the crater had been choked by debris and from under the edge of this lid the explosion forced the steam and highly heated rock and ashes down upon the great mass of snow lying on the northeasterly slope of the mountain; the resultant rapid melting produced the sudden flood which swept down Hat Creek on the morning of May 21. The actual damage to the main farming which lies fully twenty miles to the northward of Lassen Peak was greatly exaggerated in the early reports. In fact in the lower valley it is highly probable that the value of the fertilizing action of the mud more than compensated for the damage of the flood. But at the foot of the mountain and along the headwaters of Hat and Lost creeks no description nor photographs can adequately express the feeling of desolation experienced when one sees the destruction of the natural features of these valleys. The downward blast leveled the forest as if it were no more than a grain field. That the trees were blown down and not broken off by the flood which followed is shown by Plate CLII, where trees leveled by the blast lie above the highest flood line. The needles of the pine trees standing on the borders of the sharply defined path of the blast were killed by the heat of the steam and ashes.

Another feature of this eruption that has received but scant attention is the narrow fan-shaped belt of rock fragments projected for miles across the country in the direction of the Hat Creek blast. At Hat Mountain fragments ranging in size from dust particles to pieces seven inches long covered the snow on the old crater rim (Plate CLI). At Cinder Cone they were found "as large as hen's eggs” and twenty miles away about the size of ordinary marbles. At Eagle Lake, some forty miles distant from Lassen, the lapilli were of the size of coarse sand.

At the time of these eruptions the snow on Lassen Peak was so deep that it was not until May 27 that the actual crater was finally reached. In this first party were Mr. David Durst, from Susanville, and Mr. William G. Reed and the writer, from the University of California. Even with the skilful guidance of Charley Yori, of Drakesbad, in picking a path among the snowdrifts, which covered rocks and gullies alike, the party was six hours on horseback making the six miles to the little plateau at the southeast base of the final peak.

Having in mind the new chasm which yawned in the middle of the ancient crater, on climbing to the rim we were astounded to see an almost level plateau of ugly bare rocks, with hissing steam escaping from the many cracks and crevices, and over all the shimmering air indicating the heat below. Strange as it may seem, those of the party who had visited the crater before found this uplifted mass of old lava more awe-inspiring than the former depths of the crater, leading downward to the internal forces which had produced the great explosions.

Closer inspection revealed the fact that the crater had not been, filled by ejected material, but that the entire mass had been shoved bodily upward (Plate CLI). The old crater rim sloped downward some twenty feet and there met the almost vertical wall of the uplifted center with a strip of talus at its foot. Photographs taken later of the southwest and northwest slopes show the dark rocks of the uplift filling the wellknown notches in the old crater rim, notches which prior to May, 1915, gave, from some points of view, the impression of two separate peaks.

Interest in the eruptions occurring during the remainder of 1915 rests largely in the question whether they indicate that the volcano is becoming quiescent once more. Professor Diller of the United States Geological Survey has expressed the opinion that the great outbursts in May spent the present energy of the volcano and that it will again become dormant. The writer was at first apprehensive that Professor Diller's opinion was correct, but hope for continued activity is not yet lost. Eruptions have occurred at rather frequent intervals throughout the summer and fall. Many of them have thrown columns of steam and ash to a height of several thousand feet. The eruption during the night of October 30, 1915, was sufficient to cause a fall of ashes at Susanville, forty miles away, as attested by Mr. David Durst, principal of the High School at that place. The Shasta Courier of November 2 reports an eruption seen from Redding on November 1, "the most spectacular since May 22,” and estimates the ash column as 10,000 to 12,000 feet in height.

One further question should be discussed, and that is the one so often asked: “Has any real lava been thrown out? Large quantities of real lava which in a former period cooled and became solid down in the throat of the volcano have been ejected, but there is no evidence that molten lava has flowed from the crater during the present period of activity. It is of course self evident that some source of great heat has existed within the volcano for the past two years. Several of the reports that hot rocks or luminous rocks have been seen during eruptions occurring at night are too reliable to be discarded. The following extract from a letter from Miss Inez Hyatt of Sacramento, whose party was camped at Manzanita Lake, scarcely five miles from the top of Lassen Peak, is clear and definite in its testimony.

"We really did see a wonderful eruption at ten o'clock at night, June first (1915), when red-hot material shot up, looking very much like flames, and we clearly saw one huge red-hot rock roll down the slope toward Manzanita Creek. There were other rocks, too, which lodged, I suppose, near the top, but this one big rock shot far down beyond the rest. Then a big cloud of black smoke came out and hung like a big balloon over the mountain for fifteen minutes and then disappeared. It was an ideal night, dark, but clear so that all the stars were out."

Subsequently Professor Diller found rocks in that vicinity which seemed to have been recently fused on their surface. It would seem to be a reasonable conclusion, then, that molten lava, whether actually ejected or not, has been nearer the surface than usual during the recent renewal of volcanic activity.

During the present winter it is not probable that many reliable observations of the crater can be made, but the general public as well as the physiographer will await with interest the coming of another summer, which will give the opportunity to learn whether the volcano is really declining in activity or whether the slowly accumulating stress of the internal forces of the earth is to be relieved by an eruption greater than any of the past two years. It may be said, however, that downward blasts from volcanoes are relatively scarce and that the probabilities are against the repetition of the particular combination of circumstances which produced the Hat Creek flood.


June 28, 1914. View across ancient crater from southern rim, showing new

crater with escaping steam


May 27, 1915. From approximately same position, showing chaotic mass of old lava

uplifted and filling the former craters CHANGES IN CRATER OF MOUNT LASSEN

Photos by R. S. Holway

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