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Protoplasmic Life.— Mr. Crace-Calvert stated that life will become manifest in the albumen of a fresh egg mixed with pure water after an exposure of fifteen minutes to the atmosphere. Experiments in spontaneous generation are often vitiated by momentary exposure to the air.

NOTES.

Prof. Agassiz has published a letter in regard to the expedition in the Ilassler, in which, after stating that some published statements are incorrect in many particulars, he says : —

"The Hassler was built for the coast survey work of the Pacific shore of the United States. Any work undertaken on board this vessel, is, therefore, entirely subordinate to that of the regular operations of the survey. As she must, however, necessarily make the tour of the South American continent, in order to reach her destination, Professor Pierce, the Superintendent of the Coast Survey, has thought it wise to organize a scientific party, consisting of men who might render the voyage in the highest degree useful to science, as well as to the special interests of the survey itself. To this end he has provided a dredging apparatus in connection with the hydrographic operations, thus continuing on a larger scale the work so admirably conducted under his auspices in the Gulf of Mexico during the last five years. The wider range thus given to these operations will, of course, greatly enhance the value of the previous work, and lay the foundation for much more effective researches in the future.

I consider myself fortunate in being connected with this voyage, doubly so because the companions with whom I am associated are men of tried ability, some of them having a larger experience than my own in special details of the work, while Captain Johnson, commander of the Ilassler, adds to his professional skill a zeal for the interests of science warmly shared by the officers under him. But while everything has been done to give this initiative voyage of the Hassler a high scientific character, it must not be forgotten that the present expedition is simply an incident in her history. The superintendent has indeed allowed me to make collections on our way, since we sail in waters where everything that lives has special value for the naturalist; but the expense of making these collections, and indeed all expenses of the scientific party not directly connected with the Coast Survey work, will be paid from private means provided by individual liberality.

I have thought it best to publish this statement in order to make it fully understood that the scientific expedition connected with this voyage is not its chief object, except so far as that expedition subserves the best interests of the Coast Survey."

The vessel sailed December fourth, and will touch first at St. Thomas Island. The steamer burns less than three tons of coal a day, and can thus run eight thousand miles on one hundred and fifty tons of coal, a remarkable saving of fuel. Professor Agassiz has taken out abundant stores for preserving specimens, and deep sea nets and hooks specially adapted for catching fish at great depths. We also publish a letter to Professor Pierce, the Superintendent of the Coast Survey, in regard to the aims of the dredging party from advanced proofs received from Professor Pierce, and published as a Bulletin of the Museum of Comparative Zoology.

We noticed in the last number of the Naturalist the instruction in science afforded to the teachers of Boston at the Hall of the Natural History Society, the means having been furnished by Mr. John Cummings ; we should not forget the other efforts made to instruct the public and popularize science, under the auspices of the same vigorous institution, the means of which have been and are this year to be furnished by Mr. John A. Lowell, as trustee of the Lowell Institute Fund. The first courses were given for a nominal price of admission in the lecture-room of the Society's Museum, last year. The following is the programme of the lectures for this season:

"First course, beginning October 23, twelve lectures on Popular Geology by W. T. Brigham. A.M. Subjects — 'Water as a Geological Agent; Chemical and Physical Properties of Water; Dew and Rains ; Springs; Rivers ; Waterfalls ; Bogs and Marshes; Lacustine and Oceanic Deposits; The Ocean; Caverns ; Snow and Ice; Glaciers; Deluges.'

Second Course, beginning December 4, six lectures by B. Joy Jeffries, M.D. Subject —' Comparative Anatomy of the Eye, and Vision.'

Third Course, beginning December 26, ten lectures by Professor G. L. Goodale, of Bowdoin College. Subject — 'Physiological Botany, a study of some of the relations of Plants to Heat, Light, Electricity and Chemistry.'

Fourth Course, beginning January 29, six lectures by Thomas Dvvight, Jr., M.D., Subject — 'Preservation of Life among the Vertebrates.'

Fifth Course, beginning February 19. six lectures by W. G. Farlow, M. I). Subject — 'Cryptogamic Botany, with special reference to the Alga?.'

Sixth Course, beginning March 11, by F. G. Sanborn, Subject, — 'Talks about Insects.'"

T ZHI IE

AMERICAN NATURALIST

Vol. VI.-FEBRUARY, 1872.-TTo. 2.
THE MOUNTAINS OF COLORADO.*

BY J. W. FOSTER, LL. D.

Topographical Features.— The mountains of Colorado form, perhaps, the most striking feature in the orology of the United States. Regarding the several ranges which traverse the region between Mexico on the south and the British Possessions on the north as parts of one stupendous whole, whose upheaval in the main may he referred to one geological epoch, we find that along the fortieth parallel the most active telluric forces were exerted, producing the widest expansion and culminating in the loftiest peaks. Between the Sierra Nevada on the west and the Wasatch on the east, the ridges, with their intervening valleys, reach an expansion of not less than a thousand miles. Traced north and south they not only diminish in height but contract in width to about four hundred miles. There are five or six peaks in Western Colorado which attain an altitude of over fourteen thousand feet above the sea, constituting the highest ground in the United States, with the exception of a region on the head waters of Kern River where there is a single point, Mt. Whitney, estimated at fifteen thousand feet.

Between the Missouri River and the Rocky Mountains there is a great swelling of the land, which to the ordinary observer is al

•Rcail before the Chicago Academy of Sciences, November 14,1871.

Entered according to Act of Conirress, In the year 1872, by the PEABODY Academy Of 9cienc:e, ill the OiHce of the Librarian of Congress, at Washington.

AMER. NATURALIST, VOL. VI. 5 (65)

most imperceptible. Kansas City, at the junction of the Missouri and Kaw Rivers, is six hundred and forty-eight feet above tide water; First View, near the western line of Kansas, is four thousand, four hundred and seventy-nine feet; and Denver, fourteen miles from the base of the mountains, is five thousand, one hundred and five feet. Thus it will be seen that the traveller along this route is ascending a rapidly-inclined grade which to the ej-e appears as a dead-level.

From this elevated plateau the mountains rise abruptly, like a great rampart, ridge succeeding ridge, until, on the fortieth parallel, the culminating point is attained at Gray's Peak. This peak was named in honor of the distinguished botanist of that name, by one of his devoted disciples, Dr. Parry, who was the first to measure its altitude, which he found to be fourteen thousand, two hundred and forty-five feet.

There are really two culminating points to the range in this vicinity; one with a rounded outline probably a few feet lower, and the other cone-like in form, which in the distance resembles an aerial pyramid. It would not be inappropriate to attach to the southern point the name of Torrcy, who has done so much in determining the botany of the mountain region of the United States; thus linking together the names of two honored observers who throughout a series of years have worked side by side in a common science. Here is the water-shed of the continent. The rains which fall on the' western slope find their way to the Pacific through the Colorado River and the Gulf of California, and those which fall on the eastern slope reach the Atlantic through the Platte branch of the Missouri, thence through the Mississippi and the Gulf of Mexico.

Standing at Denver on a clear summer's day, the observer comprehends in the range of his vision, a view rarely surpassed in grandeur and extent. The mountains rise abruptly from the plains like a great wall which can be traced for one hundred and fifty miles. To the south is seen Pike's Peak, distant sixty miles or more, jutting into the plains, and to the north, nearly equidistant, Long's Peak, with its snow-clad flanks and bare scalp, looms up amidst the congeries of peaks. The intermediate distance is filled in with mountains of every variety of contour; some serrated, some crater-like, some pyramidal and some with rounded outlines.

The best time to view this landscape is at early morn. The mountains then resemble a great cloud-bank hanging on the verge of the western horizon. As the sun comes up illuminating the peaks and projecting crags, the landscape resolves itself into definite outlines. Over the whole are thrown broad masses of light and shade, and rock and tree and grassy slope are revealed with wonderful distinctness, while from the snow-fields are flashed back the tints of sapphire and gold. Bathed in that rare and clear atmosphere there is something in this scene ideal, unearthly. '•The Delectable Mountains" revealed to the vision of John Bunyan were not comparable in grandeur to these.

While in the distance, the mountains appear to present an impenetrable barrier, yet when approached, they are found to be intersected by numerous canons which afford practicable routes to their very heart, and enable the explorer, without exhausting effort, to scale their loftiest summits. Their arrangement en echelon affords passes which may be surmounted even by railroads.

We have, very properly, incorporated into our vocabulary the Spanish term "canon" as expressive of a torrent-stream walled in by mountains. Such is the character of all the streams which descend to the plains. Rock-bedded and often rock-walled, they rash and roar in their onward course, and only find repose after their escape to the broad undulating plains.

Ascending a summit from which a bird's eye view of the country ean be obtained, the contour of the surface appears like a confused mass of matter thrown up and corrugated when the elements of fire were in the wildest commotion. A tumultuous sea, instantaneously arrested and petrified, would be a miniature representation of what is here seen; and yet, when the geologist comes to carefully examine the structure of the mountains stratigraphically, he finds that they range in nearly conforming lines, whose direction is N. N. W. and S. S. E.

Another striking feature in the topography of this region isthe series of high table-lands known as " parks." They are verdant valleys walled in by snowy mountains. The melting snows give rise to numerous springs and rivulets which sustain an almost perennial growth of bunch grass, making these parks according to Fremont "the paradise of all grazing animals," and these streams the favorite abode of the speckled trout. The antelope, the elk, the mountain sheep and the black-tailed deer still abound

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