to complete the triangulation commenced in 1873. This important work was delegated to Lieut. Wm. L. Marshall, Corps of Engineers, who brought to this task, besides professional and executive abilities, the experience gathered in his former labors upon this work. The total area assigned was a little less than 35,000 square miles.

Out of the nine parties, six were moving field-parties, having special areas conjoining along latitudinal and other lines, and connecting at certain triangulation and topographical stations.

A special party, under Doctor J. T. Rothrock, U. S. A., organized with a view to institute further investigations into the natural history of certain areas left unfinished in 1871, 1872, and 1873, in New Mexico and Arizona, departed from Santa Fé early in the season, and returned laden with rich and valuable collections of the flora and fauna of that great region; having carried on, in connection with their examinations, observations for altitudes of special points within the drainage area visited, throwing further light upon the geographical distribution of animal and vegetable life.

Two main distinct astronomical parties were occupied in establishing the co-ordinates of points immediately adjacent to the field of survey and others along the line of the Union Pacific Railroad, and were successful in accomplishing all that was laid out for them.

The results in the astronomical branches are, the conclusions of the observations necessary to determine the co-ordinates, and the astronomical meridian at the stations Las Vegas and Cimarron, N. Mex., the latitude of Pueblo, Col., the latitude and longitude of Sidney Barracks, Julesburgh, and North Platte Station in Nebraska, on the Union Pacific Railroad.

At the field astronomical stations sextant observations were carried on by the following officers in charge of the several parties: First Lieut. Wm L. Marshall, First Lieut. P. M. Price, Corps of Engineers; Second Lieut. C. W. Whipple, Third United States Artillery; First Lieut. R. Birnie, jr., and First Lieut. S. E. Blunt, Thirteenth United States Infantry. These stations have been numerous, answering all the requirements made upon them for checking special positions by a method in place of which nothing else could be made available.

The geodetic work included the establishment of 79 main triangu lation stations, extending a net-work over the entire mountain-area occupied. Base-lines were measured at Trinidad and Pueblo, Colorado; Cimarron, Las Vegas, and Santa Fé, New Nexico. These bases control the triangulation which connects the belts of 1873 in Colorado, New Mexico, and Arizona, as well as those north and south from the line of the Union Pacific and Central Pacific Railroads.

In meteorology, except at the astronomical stations at Cimarron and Las Vegas, N Mex., the observations were conducted solely with a view to the deternmination of altitudes at prominent physical points within the area surveyed.

Though no person was actually assigned as geologist, Doctor H. C. Yarrow, U. S. A., and Professor E. D. Cope investigated the geology and paleontology of the Territory of New Mexico. The results obtained were highly interesting. The cretaceous beds yielded many fine fossil shells and teeth of extinct fishes, and the carboniferous limestone was found to be equally rich in specimens. A unique collection of a large number of beautifully preserved invertebrate remains was procured from the same formation. These are the deposits of a lake of a comparatively modern age, which abound in the remains of skeletons of the animals that inhabited the surrounding land. Mastodons of species quite different from those frequently found in the Eastern States were in abundance, while camels and horses had evidently existed in droves. One of the most singular discoveries was that of a deer which did not shed its horns; and the fossil remains further indicate that at this time several species of wild dogs existed to keep in check the herbivorous animals, while a large vulture, allied to the turkey-buzzard, was prepared to act as scavenger as occasion offered. In another locality crocodiles and turtles were very numerous. Among the large remains were those of the genus Bathmodon, which closely resembles the elephant in the feet and legs, but the tapir and the bear in the character of the skull. They were armed with formidable tusks, and their crania were very thick, as if designed to repel attacks.

In the line of archæology and ethnology were found the remains of ancient human dwellings which stand in lines on the summits of rocky crests, and on the more inaccessible and remote points of hills, with precipices of several hundred feet in depth on one or more sides; from these and burial places most interesting specimens of pottery, besides crania and skeletons, were obtained.

The mineralogical specimens collected have been carefully analyzed by Doctor Oscar Loew in the laboratory of the Smithsonian Institution. Dr. H. C. Yarrow, in charge of the natural-history branch, with his assistants, have added more largely than ever before to our knowledge of the living fauna of large interior areas. Their results are soon to be worked up by themselves and other specialists, and the specimens afterwards deposited in the National Museum at the Smithsonian Institution.

As usual, a photographer accompanied the expedition, who this year was successful in obtaining special photographs of ancient ruins, of various Indian tribes, &c.

While the parties operated in the field, the office-force remained engaged in working up the results for publication.

The publications during the past year of the surveys under the War Department have been: the Progress Report of 1872, a preliminary catalogue of plants gathered in 1871, 1872, and 1873, and a preliminary report upon the ornithological specimens collected in the same years; the first in quarto, the two latter in octavo. An advance edition of the Topographical Atlas and other physical sheets was also published.

The total working-force taking the field without escorts, for the first time, was 86, including officers, assistants, and employés. The utmost harmony existed among all the parties, which largely conduced to correspondingly enhanced results. In regard to these surveys under the War Department, the following paragraph appears in the Annual Report of the Chief of Engineers to Congress: "By experience and improvements in methods and instruments, the value of the results is annually enhanced, and the cost of the work amply repaid."

It cannot fail to be gratifying to all who are interested in this class of investigations to be convinced that the proper basis for further systematic endeavor has been reached.

Survey under Professor Hayden.

This survey during the season of 1874 continued the work of 1873 west ward of the 107th meridian of longitude in Colorado Territory. The entire area explored lies on the west slope of the main range of the Rocky Mountains, forming the eastern part of the drainage of the great Colorado River. The topographical and geological work included a carefully-surveyed area of about eighteen thousand square miles, much of it comprising some of the most rugged and mountainous scenery on the continent. The southern portion includes an area of nearly three thousand square miles, the greater part of which is at an elevation of 12,000 feet and upward. The first division of the party, under Mr. A. R. Marvin, operating in Northwestern Colorado, established 86 stations; the second division, under Mr. Gannett, which explored the rugged area between the Gunnison and Grand Rivers, also established 86 stations; while the third division, surveying the remarkably high country in the southwest, determined 65 stations, most of them being on peaks ranging from 13,000 feet and upward, the highest being 14,500 feet.

A fourth division, under Mr. G. R. Bechler, performed the important duty of measuring the roads, trails, passes, and carefully working up the contiguous topography, besides meandering a distance of about nine hundred miles. Mr. Bechler established 36 important stations, thus rendering more accurate and complete the general work of the survey. A fifth party, under Mr. W. H. Jackson, the photographer, passed over the greater portion of Western Colorado, obtaining about four hundred negatives of the most characteristic scenery. These views have proved of great value in the topographical and geological studies; but the most interesting result was a series of views of the wonderful ruins in the cañons of the Mancos and Montezuma Rivers. The party found here remains of a rude civilization in the form of buildings, made of hewn stone laid in mortar. Among the ruins were various kinds of stone implements and glazed pottery, on some of which were figures of the sun. On the plains and mesas these ruins occupy considerable areas, indicating the former existence of a numerous population. In the cañons the stone dwellings are built high up in the caverns or crevices in the

sides, from 800 to 1,000 feet above the bottom, in almost inaccessible positions. From all the information that could be obtained from the present race of Indians, these dwellings were inhabited at least eight centuries ago by a race of sun-worshippers, which were driven southward, step by step, by a persistent foe from the north.

The sixth division, under Mr. J. T. Gardner, continued the primary triangulation over the mountainous region of the southwest, extending into Utah, and connecting with some of Professor Powell's stations.

The seventh division was under the immediate direction of Professor Hayden, and made special studies of those portions of Colorado that presented rather complicated problems in geology. A careful survey was made of the Elk Mountains, of the Morainal deposits in the valley of the Upper Arkansas, and the coal-beds along the east base of the Colorado range of mountains from Cañon City to Cheyenne. The season's labors were in every respect successful, and a large amount of topographical, geological, and natural-history material was secured for the eighth annual report to the Secretary of the Interior.

The publications of the survey during 1874 were the Bulletin No. 1 and No. 2, and second series, Nos. 1, 2, 3; miscellaneous publications, Nos. 3, 4, 5, 6; Cretaceous Flora, by Leo Lesquereux, 7th Annual Report, (Colorado.)

Survey under Professor Powell.

This was the continuation of the geological and geographical exploration of the basin of the Colorado of the West in Utah, prosecuted for several years previous. For this work two parties were organized, one under the charge of Prof. A. H. Thompson, and the other under the immediate direction of Professor Powell himself. Each party had a number of assistants, and to the latter was added a photographer. The first party was employed in carrying forward the work in Central Utah, and the second party in Northeastern Utah.

The valley of the Sevier, near the town of Gunnison, was selected as the proper position for the base-line from which a series of triangles could be extended to the north, east, and south, and connected with those which had been established in former years.

For hypsometric determinations Green River City on the Union Pacific Railroad, Salt Lake City, Gunnison, and Pangwitch were selected, from their connection with railway surveys, as known points of reference for altitudes to be ascertained by the barometer.

The geographical determination of latitude and longitude rests primarily on the base-line, the terminations of which were established by astronomical observations. For latitude the zenith-telescope was employed, and for longitude telegraphic methods were adopted.

The material was collected for mapping and exhibiting the resources of a section of country heretofore but little known, embracing many ranges of mountains and plateaus, with valleys drained by streams

which in places pass through deep and almost inaccessible gorges. Over the entire region surveyed the data were collected for determining the amount and distribution of lands which can be redeemed from sterility by irrigation, and also that of grass and timber lands. The coal-formations, which had been discovered in previous surveys in adjoining regions, were traced through the areas of the present survey, and many new beds discovered. It was found that the coal of Southern and Central Utah is distributed through a series of geological formations embracing most of the Tertiary and Cretaceous ages. The supply of coal of this region is, therefore, abundant, and much of it is said to be of good quality and widely distributed. The position of many of the more important mineral-lodes was determined, especially such as have been worked to a sufficient extent to enable the owners to acquire permanent titles from the Government, and these will be represented on the general map.

The geological structure of the region is exceedingly complex. A series of formations, embracing Tertiary, Mesozoic, Paleozoic, and Metamorphic rocks, are plicated on a grand scale, and displaced by faults of immense extent. During geological ages, and continued down to later periods, this region must have been the scene of great volcanic activity. Extensive fields of eruptive matter and large numbers of volcanic cones are exhibited. In many places there exist great escarpments, forming cañonwalls and lines of cliffs, exhibiting with great perfection the superposi tion and structure of rocks, from which interesting geological deductions can be made.

The great system of monoclinal folds and faults discovered in former years, crossing the grand cañon of the Colorado, was found to be extended into the region of this year's survey. The lithological geology was studied so far as the opportunities permitted, and large collections of rocks made, especially of the volcanic formations widely distributed in geological succession. From the sedimentary rocks fossils were obtained abundantly sufficient to indicate the ancient flora and fauna of the region. The Territory is traversed by profound gorges, which conduct off the small amount of rain-fall not evaporated. Although the amount of water carried by the streams is small, the great elevation of the country above the sea gives it the velocity of a torrent, and being mingled with stones, its erosive action exhibits effects unequalled, perhaps, in any other part of the globe. On the mountains and plateaus of this region, wherever an altitude of 9,000 feet, or more, is reached, evidences of ancient glacial action are found.

Interesting ethnological results were obtained. Two important tribes of Indians were again visited, the Ú-in-tats and Seuv-a-rits, usually known as the Uinta Utes and She-be-riches, and much additional knowledge of the words and grammatical construction of their language was secured, as also a series of facts relating to the naming of tribes. and confederacies, with fresh information as to their political organiza