Page images
PDF
EPUB

he required four and a half hours on the mountain to perform experiments which took less than three hours in the valley. Here we have something like a numerical measure of the falling off in ability due to great altitude.

Hitherto I have only spoken of the discomforts and inconveniences of mountain stations at very high levels. It is necessary to recall the positive danger incident to such establishments. A glance at the illustrations of this article, or a reference to Mr. Serviss's account of his ascent of MontBlanc in August, 1895, (see McClure's Magazine for May, 1896,)1 will exhibit the risks which must be met in the ascent or during the more dangerous descent. "Men have lost their lives here and will again lose them," is the remark of Mr. Conway, the Himalayan climber, in speaking of the Petit Plateau. "The Grand Plateau has taken more lives than its ill-starred neighbor below." In describing the loss of a party of climbers Mr. Serviss makes the grewsome remark, "Every boy in Chamounix understands how a dead body should be brought down from Mont-Blanc."

A few such references tell the tale. It is not necessary to quote the long list of persons who have met their death on the mountain.

On August 15, 1891, a party of workmen were engaged in excavating tunnels at the summit of Mont-Blanc in connection with the building of M. Janssen's observatory. Here is the diary of their work:

[blocks in formation]

and the perils of the journeys to and from the summit.

In a volume which has just reached this country M. Vallot, who has a meteorological station on the flanks of Mont-Blanc, presents some pregnant criticisms on the plan of M. Janssen which has resulted in the establishment of a permanent astronomical observatory at the very summit. the difficulties that were predicted beforehand have been met, and some of them are quite insuperable. The experience of the past few years has made it very probable that the building of this summit station will prove to have been an expensive mistake.

Ava

Transportation presents no great difficulties until the line of perpetual snow is reached. Among the glaciers everything must be carried by porters. The ordinary load for Mont-Blanc is from thirty to fifty pounds and the price per pound to the summit is fifty-two cents. Single pieces weighing as much as one hundred and thirty pounds have been transported but at a special rate of payment. The ascent of Mont-Blanc is often impossible for a week at a time (and this in the summer season) and the observer must be provided, for a siege of this length at least, with every necessary of life. It is not storms alone that render the ascent dangerous. lanches and ice-falls are frequent. Cold and snow blindness are two great drawbacks, which interfere with the work of the observer far more seriously than with the progress of the mere mountain climber. The very high winds materially increase the discomfort from cold. Electric storms and lightning constitute a real danger. The observatories on the mountain are provided with lightning rods, but the difficulty of making a ground connection remains. M. Janssen's observatory at the summit has already been struck. The problem of heating is a serious one. Wood or coal is practically out of the question as fuel, and petroleum must be used. The air of the room must be frequently renewed or its oxygen is soon exhausted so far as to produce nausea. Water for drinking and cooking must be provided by melting snow, and this is a work that never ends, for it is impossible to store water in reservoirs or tanks. It soon freezes, of course, and all has to be begun once more. After great

difficulties the instruments of the summit

[graphic][merged small]

The Summit of Mount Hamilton in the Winter (4209 feet)

observatory have been mounted, but the self-registering meteorological apparatus has so far failed to run continuously. Cold, frost, snow, the thickening of the oil, the change of level of its foundations, etc., etc., have prevented continuous observations at the summit. The twelve-inch telescope is mounted in a fixed position with a movable mirror which reflects the celestial object into the field of view. Nothing has yet been done with this instrument, so far as is known.

It is probable that mountain-sickness will always be a great obstacle in the way of continuous observation at the summit. It is possible to become acclimated, no doubt, but the fact remains that from this and other causes the Janssen observatory has so far yielded few or no scientific results. The expeditions of the years 1894, 1895, 1896, have not succeeded in their scientific work, in spite of brave efforts, because they were undertaken by scientific men who were not mountaineers, or else because of interruptions from storms or fog. Finally, it is a commentary on the real difficulties to be encountered to say that the director of the Janssen Observatory (M. Capus) has not yet succeeded in reaching it! His three attempted ascents have all been interrupted at the Grande Mulets by bad weather.

In a work which has just been printed by the Smithsonian Institution' I have studied at some length the conditions suitable for astronomical observations at high levels. It was necessary, also, to examine the records of meteorological mountain stations, and to inquire how far the scientific use of balloons and kites might enable us to do away with permanent observatories on mountain-peaks. The advantages of suitable high level stations (as for example, Mount Whitney and Mount Hamilton in California; and the Harvard Observatory annex at Arequipa in Peru) are very great. Doctor Henry Draper, in 1877, reported that only three nights in two years gave him good lunar photographs at his observatory at Hastings-on-Hudson. In August, 1888, photographs of the Moon were made at the Lick Observatory on August 12, 13, 14, 15, 16, 17, 18, —, 20, 21, 22, 23, 24, 25, 26, 27, 28, 30, 31. All of these pictures were good and some of them were

1 Mountain Observatories in America and Europe. Smithsonian Miscellaneous Collections, 1896.

superb. Mount Whitney and many points in California would have given equally good results. results. It follows from the 1891 diary of the Mont-Blanc party just quoted that only four days were working days. There is no record of the clear nights, but there could not have been more than four, and there were probably not so many.

The summit of Pike's Peak (14,134 feet) was occupied from 1874 to 1888 as a meteorological observatory by the U. S. Weather Bureau, and it has been chosen at various times as an astronomical station. Since the year 1891 a railway has connected the summit with the valley beneath (Manitou). The air of the mountain is extraordinarily clear, except during the prevalence of bush-fires, and the snow-fall and temperature permit a continuous residence at the summit. The steadiness of the air is, however, very unsatisfactory, and all observers have advised against establishing a large telescope at this point. Pike's Peak is, like the generality of mountains, unfitted for a permanent astronomical station. Mont-Blanc is far less satisfactory.

There is a class of observations which require astrophysical stations temporary camps-to be established at high levels in connection with other stations in adjacent valleys. M. Janssen's first observations on Mont-Blanc are a case in point. The spectrum of the sun, seen from Chamounix, shows some lines which may be due to oxygen in the atmosphere of the sun. On the other hand, these lines may be due to absorption-effects of the earth's own atmosphere. A simple method to decide the question is to examine the solar spectrum from a high-level station. If the spectral lines are due to the effects of our own atmosphere they will be less and less distinct as higher levels are reached. comparison of observations on the peak and in the valley will at once decide such questions; and it was by such a process that M. Janssen showed the absence of oxygen in the sun. The spectral lines were due to the earth's atmosphere.

A

Again the object of Professor Langley's expedition to Mount Whitney (1881) was to evaluate the amount of heat sent out by the sun in a unit of time. To do this it was necessary to measure the amount of heat absorbed by the earth's atmosphere. This was accomplished by comparing simul

[graphic][merged small]

The Astronomical Observatory on the Summit of Etna (9,652 feet)

taneous heat-observations made at the summit and at the base of Mount Whitney. There are a number of such problems in astrophysics and it will be necessary, from time to time, to occupy mountain peaks to obtain the required solutions. But it must be borne in mind that such problems do not require the permanent occupation of mountain-stations. They are occasional in their nature and the establishment of a scientific camp during a few days or weeks is all that is required. Such camps should be placed in the most favorable situations, chosen so as to give the greatest amount of clear weather, the greatest facility of access, the least discomfort and danger to the observer. Pike's Peak, for example, would have served M. Janssen's purpose as well as Mont-Blanc (its summit is at the same height as the point from which the first observations were made) and it is accessible by railway and road. It is possible to ride nearly to the summit of Mount Whitney, which is only 881 feet lower than Mont-Blanc. The weather-conditions at both the American stations are far more favorable than those of Mont-Blanc. Astronomy does not require the permanent occupation of such elevated stations. For the solution of special problems by special expeditions favorable and not unfavorable conditions should be chosen.

High level meteorological stations have lately been established in great numbers, and a few such stations will always be needed. The stations on Mount Washington (6,279 feet), on Pike's Peak (14,134 feet) in this country, and those on the Säntis (8,200 feet), the Sonnblick (9,843 feet), etc., in Europe, are the best known. For a solution of many of the problems of meteorology it is necessary to compare the temperatures, the winds, the moisture, etc., at high and at low levels. The cost of establishing such stations need not be great, and as self-registering instruments are gradually perfected, it will become unnecessary to keep permanent observers employed in such work. An occasional visit will suffice. Experiments with balloons have shown that the records from such stations are quite unsatisfactory, at the best. The balloon floats in free air and its meteorological instruments give the data exactly as they are required. On the other hand a mountain station at the height of the balloon is effected by a host of purely

local conditions. The winds blow upwards along the slopes; the temperatures are affected by rocks or snow-fields, etc., etc. It is often impossible to determine the proper corrections to apply to the readings of instruments placed on mountains to reduce them to what they would have been if taken from a balloon.

Since the first scientific balloon voyage (by Doctor John Jeffries of Boston, in 1784) immense progress has been made. Free balloons carrying only self-registering instruments (no observer) have lately been brought to great perfection and an extreme height of eleven miles has been reached. In order to make further progress in meteorology it is necessary to have recourse to balloons, and the data from mountain stations, while of value, will become of less and less importance. They are too much affected by local topography. The disturbing effect of mountain masses can not be eliminated.

Just as balloons must be used for great heights, so kites must be employed for lower altitudes. An article in McClure's Magazine for March, 1896, ("Scientific Kite Flying") may be consulted for details of the new art of kite-making and kite-flying. It is sufficient for my present purpose to note that kites have been raised over five thousand feet, and that it is comparatively easy to send self-registering instruments to heights of two thousand and three thousand feet. Iustruments so exposed give precisely the data that are wanted.

Balloons and kites must be depended on for the most refined data in meteorology, and it is now of little use to collect data of inferior precision.

The slight cost of balloons and kites compared with the expense of installing and maintaining mountain-stations is a point which must not be overlooked.

In what has gone before the great advantages of suitable astronomical stations at high altitudes has been pointed out. A telescope on Mount Whitney, for example, would not only have the advantage of a whole summer of cloudless days, most of them free from haze or smoke, but it would also be most favorably situated with regard to the steadiness the absence of twinkling of the stars. Delicate observations. could be successfully made, and high magnifying powers regularly employed. The twelve-inch Equatorial which has lately been

« PreviousContinue »