posit, probably of Miocene age, astonishingly rich in insect remains, many of them beautifully preserved. During the past year about 20,000 insects have been exhumed from this single locality; and scarcely an impression has been made upon the quarries, although perhaps more labor will hereaf ter be required in working them. In company with Professor Lakes, of Golden, they made as careful a survey of the basin in which they occur as their short stay permitted, and estimate the insect - bearing shales to have an extent fifty times as great as the richest localities known in Europe.

The geographical and geological survey of the Rocky Mountain region under Major Powell, to which, from its departmental connection with Dr. Hayden's survey, attention is next invited, confined its operations the past season almost entirely to the central portion of Eastern Utah, an area containing about 16,000 square miles, embraced between 38° and 40° 30' N. lat. and between 109° 30' and 112° W. long. Nearly the whole of this region is drained by the Green River and its affluents, before it unites with the Grand to form the Colorado, and is one of the most arid, inhospitable, and inaccessible in the country. It is an elevated plateau, cut by a labyrinth of cañons and narrow gorges, and covered in many parts by hills of naked sand and clays. The western portion, however, includes broad valleys, abrupt ranges of mountains, and one plateau of considerable extent, having an average elevation of 8000 feet. The valleys, which contain large areas of excellent land, run north and south, separated by three ranges of mountains, rising in their highest peaks to from 10,000 to 12,000 feet, and are drained by streams flowing westerly into Utah Lake.

With Pleasant City, a little town about one hundred and twenty-five miles south of Salt Lake City, as a base of supplies, three parties were organized — one for geodetical and two for topographical work. The triangulation was extended over the entire area selected. The work rests upon baselines established in former years near Kanab and Gunnison, Utah, and was connected on the east with the triangulation points established by Hayden's Survey, and on the north with those of the Fortieth Parallel Survey under Mr. King. On account of the rumored hostility of the Utes in a portion of the district (rumors which proved groundless), the trian

gulating party was united for a portion of the time with one of the topographical parties for mutual support. This party took the eastern portion of the field, which is separated from the western at not far from 110° 30′ W. long., and includes that part of Utah above 38° N. lat. which lies east of the Green and Colorado rivers - in all about 10,000 square miles. The party carried the secondary triangulation over this district, with stations averaging ten miles apart; made a connected plane-table map of the whole, and complemented the work with orographic sketches.

The second topographical party, occupying the western portion, was assigned an area more mountainous than that to the east, embracing about 6000 square miles: in this it occupied topographical stations at average distances of about ten miles, and measured all the angles of nearly every triangle in the secondary extension; and, like the first party, made sketches and a plane-table map of the entire area.

Besides this purely topographical work, mercurial barometers were carried by each field party; and observations were made to connect every camp with the base-station at Mount Pleasant, where observations were taken four times a day, and also hourly during eight days in each month. All the geodetic points and topographical stations were also connected by barometric observations, either with the camps, the base-station, or both; and the altitudes of all located points were observed by the measurement of vertical angles.

This hypsometric work is deemed by the director of the survey to be of the greatest importance in the classification of lands, and in determining the best methods of utilizing the waters of streams for irrigation. On account of its practical utility to the agricultural industries of the country, Major Powell suggests the establishment of a hypsometric base-line from Lake Michigan to the Pacific Ocean, from which lateral lines could be run to the base-stations used for each season. The methods of levelling by which were determined the elevations of points along the Pacific Railway (now used as a general base) were not of sufficient refinement for present needs. The work requires great care and thorough discussion, and should be undertaken by the Interoceanic Geodetic Connection of the Coast Survey. New tables also should be made, based upon series of observations in

the Rocky Mountain region itself, at stations connected by careful levelling, both with each other and a determined. base. Those now in use are founded on observations at somewhat distant points in Switzerland, under climatic conditions greatly different from those obtaining in the Rocky Mountains. Such a series of observations, however, would need to extend over long periods to attain the desired result.

Besides the three parties mentioned, separate geological investigations were carried on in other parts of Utah by Mr. Gilbert and by a party under Captain Dutton. The classification of lands occupied much of their attention. Mr. Gilbert traversed that portion of the drainage basin of Great Salt Lake which lies in Utah: it includes within its limits the most valuable land of the territory, as well as some of the most sterile, where the possibility of agriculture depends on the possibility of irrigation. By measuring the volumes of the streams, an attempt was made to ascertain the agricultural capabilities of the river valleys. Some of the smaller ones proved inadequate to serve the lands, otherwise arable, through which they run. East of the lake more than twelve per cent. of the district is reclaimable; while west of it only a fourth of one per cent. is of value for farming. It is also estimated that about two and one third per cent. of the whole territory of Utah can be redeemed by the utilization of the streams, but without the construction of reservoirs; and that one third part of the irrigable lands of the Salt Lake basin is now under cultivation.

An investigation was also made of the climate of the district, as recorded in the rise and fall of Great Salt Lake. Until recently, no systematic record of its fluctuations has been kept; but from inquiry among the settlers it appears that the water is now much higher than formerly. From 1847 to 1850 it was low; then for five years it rose at about the rate of one foot per annum, afterwards fell to its original level (in 1861-62), and then continued to rise until 1868, when it reached its present height-ten feet above that first observed-which, with slight fluctuations, it has maintained ever since. Since the area of the lake is much greater with this increased altitude, and the loss by evaporation correspondingly increased, the inflowing water must be one tenth

part greater than formerly. Should it fall to its former level, it is plain that the possibilities of irrigation would be diminished.

It further appears by the studies of this geologist that the system of upward and downward movements by which the mountain ranges of the valleys of Utah and Nevada were produced have continued down to the present time. Evidences of recent movements have been discovered on the lines of ancient faults. The old shore-lines of Great Salt Lake, indicated by bench-marks upon the surrounding mountains, are no longer level, but have been elevated or depressed with the displacement of the mountain masses. Differences of nearly one hundred feet are found in the immediate vicinity of the lake, where the ancient shore-lines lie a thousand feet above their present level; but the barometer indicates that the discrepancy is greater at more remote points.

The geological party under Captain Dutton explored the plateaux drained by the Sevier River and its tributaries in Southern Utah, making a special study of the distribution of the eruptive rocks, and the methods and results of atmospheric degradation. Particular attention was also given by all parties to the extent of the forests, and the fact elicited that the area where standing timber is actually found is very much smaller than the areas where the conditions are such that timber should be growing spontaneously-that is, the timber area is but a small fraction of the timber region. Since the destruction of forests by fire greatly exceeds their removal for economic purposes, the best method of preventing these fires is an important problem.

In addition to these various labors, the survey has been collecting with great care and pains most valuable ethnographic material, particular attention being paid to vital statistics, the discovery of linguistic affinities, the progress made by the Indians towards civilization, and the causes and remedies for the inevitable conflict that arises from the spread of civilization over a region previously inhabited by savages. It is believed that the publications of the survey in this direction will have a peculiar value.

Passing now to the geographical survey west of the one hundredth meridian, carried on by the corps of engineers under the immediate charge of Lieutenant Wheeler, we find that

the expedition of 1877 entered the field early in May, with a force aggregating forty men, divided into three sections. Six main and four minor parties traversed and gathered mapmaterial in portions of Colorado, New Mexico, Texas, Utah, Wyoming, Idaho, Montana, Nevada, California, and Oregon.

A special feature of the expedition has been the elaboration of the over- and under-ground survey of the Washoe mining region, containing the well-known Comstock lode. The contour of the entire district has been completed, and will be delineated on a scale of one inch to five hundred feet; while the profiles at distances of one hundred feet, showing the position of vein-matter, ore-bearing bodies, and adjacent country rock, have been well advanced. The position and extent of the drifts have been determined at most levels, and an extended longitudinal section of the entire vein is nearly completed. In this labor the mining superintendents and local engineers have greatly assisted Mr. J. A. Church, M.E., in charge of the work, by contributions from their store of detailed maps, which show the underground openings of all the prominent mines. This special survey, when terminated, will furnish a complete analysis of all branches of silver-mining as conducted at this peculiarly interesting mining centre, typical of its kind, and will supplement the admirable work in this same district made a few years ago by Mr. Clarence King.

Data were also gathered for constructing a detailed topographical map of the Lake Tahoe region, in the Sierra Nevada, on a scale of an inch to a mile. The other field parties were engaged in surveys necessary for obtaining material for a topographical map, on a scale of one inch to eight miles, of the entire western mountain interior.

The area covered by the examinations of the geologist, Mr. A. R. Conkling, extended in the Sierra Nevada from San Andreas and Placerville on the west, to the Como Mountains on the east. This region was found to be composed of igneous and metamorphic rocks, to the almost complete exclusion of sedimentary rocks. The most common forms are diorite, basalt, hornblende, porphyry, feldspathic porphyry, and volcanic breccia. Many Tertiary Unionidæ, and also bird-tracks, were found at the quarry near Carson. Signs of glacial phenomena were noticed in many localities, be

K