third part contains fac-similes of state papers, royal letters, and other documents, both public and private, belonging to the reigns of Queen Mary and Queen Elizabeth. Among those of the former are autographs of her Majesty and of her cousin and rival, Lady Jane Grey, holographs and autographs of King Henry the Second, of France, the King of Hungary Cosmo de Medici, the Lady Elizabeth of England, Thomas Gresham, Roger Ascham, &c. Among those of the reign of Queen Elizabeth, besides those from herself, are letters of Mary Queen of Scots and her husband Bothwell, and of the most distinguished nobles of Scotland; of John Knox, Sir Humphrey Gilbert, James VI of Scotland, Sir Francis Vere, Sir Walter Raleigh, and other celebrated personages. The exaggerated terms of courtesy which were in use among eminent personages at that period are illustrated by several examples in this volume. The publication of the fac-similes of these valuable and interesting documents is to be continued, and we learn from the preface that similar fac-similes of the national manuscripts of Scotland have been undertaken, and those of Ireland recommended.

It may be proper to recall the fact that the library of Smithson, or so much of it as was received by the Institution, with his personal effects, was not destroyed by the fire, and has been placed in a suitable case for permanent preservation.

Mr. Theodore Gill, who was formerly assistant in the library of the Institution, has been appointed one of the principal assistants in the national library, but he still continues his investigations in natural history at the Institution, and acts as the intermediate agent between the two establishments. Miss Jane Turner, who vindicates by her accuracy and efficiency the propriety of employing her sex in some of the departments of government, still continues to register the books as they are received through the extended system of international exchange.

Gallery of Art.-The original act of Congress organizing the Institution directed that, in addition to the support of a museum, library, &c., provision should also be made for a gallery of art. In compliance with this direction a commencement was made by the purchase of a series of valuable engravings, illustrative of the progress of the art from the earliest times, and also a series of Indian portraits was received on deposit. With these and a number of plaster casts of distinguished individuals, principally donations, a collection of articles was formed to which the name of a gallery of art was given. The Indian portraits, which had been deposited by the author, Mr. Stanley, together with a series of portraits also of Indians, belonging to the government, were destroyed by the fire. Fortunately the engravings, with few exceptions, were saved, and are now deposited with the books in the library of Congress. It was evident, however, that the proportion of the Smithson fund which could be devoted to the purchase of specimens of art worthy of preservation in a public gallery at the seat of government was far too small to do anything of importance in this line. It was therefore with

gratification that the Regents learned that a citizen of Washington, William W. Corcoran, esq., with an enlightened liberality, commensurate only with his means, had resolved to found an institution exclusively devoted to art. This design, which would otherwise have long since been fully carried out, was interrupted by the war. The large building which Mr. Corcoran had erected for the purpose was found necessary by the government for the use of the Quartermaster General and is still retained in possession of that officer. As soon as possession of it is restored to Mr. Corcoran, which it is believed will be done in the course of the present year, it, together with a liberal endowment equal in amount to the original fund of Smithson, will be given in charge to a board of trustees, who will immediately proceed to carry out the views of the generous founder. In accordance with the policy which the Institution has adopted in regard to the library of Congress, the Agricultural Department, and the Army Medical Museum, it will probably be considered advisable to enter also into friendly co-operation with this new establishment, and instead of attempting to support a separate gallery of art to turn over to it the articles which have already been collected, and thereby increase the space in the Smithsonian building for articles of natural history and ethnology.

Meteorology.-It was stated in the last report that with the diminished expenditure on the building, and the larger amount which could be appropriated to the active operations of the Institution, the reduction and discussion of the meteorological material which had been collected for 20 years would be resumed, and that we had commenced upon the rain-fall of the North American continent. Observations relative to this subject from upwards of 1,200 localities were placed in the hands of the computers. This work has been completed under the direction of Mr. Charles A. Schott, and will be put to press as soon as the illustrations are engraved. We are confident it will be considered by all who are competent to properly estimate its value, as one of the most important additions to the climatology of North America and the agricultural interests of the community which has ever been made. The same computers are now engaged upon the large amount of material relative to temperature, but the reduction and discussion of these will require more time than that which has been devoted to the rain-fall. It is estimated, however, that at the rate at which the work is now going on, it will be completed in the course of the next year.

The discussion of all the observations relative to the winds has been resumed under the direction of Professor J. H. Coffin, of Lafayette College, Pennsylvania, and will be prosecuted with as much rapidity as the nature of the subject, and the assistance afforded him, will permit.

All the more important meteorological observations which have been collected at the Institution during the last 20 years, are now in process of reduction, and when completed and the results published, we think

they will fully justify the expenditure of the Smithson fund which has been devoted to this subject.

The importance of a thorough knowledge of the climate of a country in relation to the well-being of the inhabitants can scarcely be overestimated. The character of the animal and vegetable productions of any part of the world mainly depends on the climate, and if, as in geological periods, we suppose this in any case to undergo a change, we are certain, from the operation of general laws, that the fauna and flora of the region will undergo a corresponding change. It is true that civilized man has in a degree, through science, the power of resisting the influence of climate to which his race has not been long subjected, yet if sufficient time be allowed for the weather to produce its effect, marked peculiarities of physical constitution and even mental characteristics will eventually be produced, though these will be somewhat modified by the artificial conditions which have been introduced. Even a difference in the degree of moisture of the atmosphere has been shown by a critical observer to induce marked changes in the manners and customs of Europeans in their emigration to this country.

The average temperature and moisture of each region, as well as the periodical fluctuations to which these elements are subjected, are essential data on which to base the choice of special objects of culture and to estimate the probable results as to success or failure in a given number of years. It is a fact to which the statesman and the intelligent farmer cannot be too much alive, that the great material prosperity of this country in the past has been due to the large quantity of fertilizing material originally in the soil, and that this has been exhausted to a far greater extent than is generally supposed. It is well known that the same soil which in the eastern States originally yielded 30, and in some cases 40 or 50 bushels of wheat to an acre, now produces but eight or ten. From a late estimate by the Commissioner of Agriculture the average yield of the whole United States is less than 12 bushels, while that of Great Britain is 28; the great excess of the latter over the former must be mainly due to the improved methods of agriculture. Indeed with the large extent of virgin soil in this country, producing spontaneously rich harvests, with the expenditure of a minimum amount of labor, we have had comparatively little necessity to adopt methods of scientific agriculture, but we have now arrived at the condition in which every year a new demand will be made for the application of knowledge and skill of this kind, and for all the light which can be shed upon the subject by meteorology, chemistry, physiology, and other branches of science.

It will be remembered that the meteorological system of the Smithsonian Institution was in a considerable degree interrupted, particularly in the southern States, on account of the late war. We have, however, during the past year succeeded in obtaining a number of copies of registers which were continued with but little interruption through the whole

period of the disturbance, and have also supplied a deficiency occasioned by the loss of the registers of 1860 in the fire which occurred at the Institution in 1865. For the purpose of exhibiting the extent of the material in possession of the Institution, and to give credit to the faithful and persevering observers who have so long gratuitously furnished contributions to this branch of science, there is given in the appendix to this report a full list of all the observers and of all the stations where records have been made from the beginning of the year 1849 to the end of 1868. The whole number of observers at present reporting to the Institution is about 400; of these 74 are furnished with full sets of instruments. The number of observers under the direction of the army is upwards of 100, of whom 50 are supplied with standard barometers and other compared instruments. With this combined system, interspersed with full sets of standard instruments, trustworthy data is obtained for determining the general climatology of the country. It is true that many of the instruments in use are not as perfect as could be desired, yet they serve to indicate differences in the elements, and thus afford the data for tracing the progress, as it were, of waves of atmospheric pressure, and also of waves of changes in atmospheric temperature.

Anticipating the important benefits which may result to our system of meteorological observations, particularly to those which relate to the prediction of storms on the Atlantic coast, we look forward with much interest to the completion of the Pacific railway. A well equipped physical observatory placed at the highest point of the road, namely, "Sherman's station," is very desirable, and we think it probable that assistance from the railway company may be obtained to establish and support an observatory of this character.

During the past year a large number of rain gauges of a simple form, such as were mentioned in the last report, have been procured and distributed to observers in various parts of the country. This gauge consists of a hollow cylinder of tinned iron 2 inches in diameter, and 12 inches in height, coated inside and out with varnish to prevent rusting. The depth of rain is measured by inserting a graduated scale into the gauge, and noting the height to which it has been wetted, in tenths and parts of tenths of an inch. The quantity of water in a fall of snow is measured by melting a column equal in diameter to that of the gauge. This is obtained by pressing the gauge, mouth downward, through the snow to the ground and isolating the contents by passing under the mouth of the gauge a thin plate of metal. A rain gauge of this form, after an experience of many years, is found to give the most satisfactory results when used by ordinary observers.

The discussion of all the material which we have collected in regard to rain-fall, has served to point out the parts of the country in which the registration is most deficient, and exertions have especially been made to obtain observations from the great plains of the west and at the base of the Rocky mountains. The great current of the return trade wind,

which continually flows through the higher regions of the atmosphere over the whole United States and which at intervals reaches the surface of the earth, deposits its moisture, obtained from the Pacific, on the Sierra Nevada and other chains of the Rocky Mountain system, and thus gives rise to the arid basins and woodless plains of the western portion of our domain. A part, however, of this region may be rendered arable by means of irrigation, or, in other words, a portion of the precipitated vapor may be, as it were, reclaimed for agricultural purposes, by artificial means; and in determining the available resources of the country it is important that the amount of water, either in the liquid state or in the form of snow, which is precipitated in the mountains, should at least be approximately determined, and hence we have directed special inquiries to this point, supplying rain-gauges in all cases of explorations and giving definite directions as to ascertaining the depth of snow, the gauging of streams, &c.

Much has been written on the subject of reclaiming arid wastes by planting trees, but the facts which have been collected in regard to this matter are frequently misinterpreted, and the result of much research in reference to it misapplied. It should be recollected that trees cannot grow without moisture and that they have no power within themselves to create this essential element of their existence. It is true that in some cases where moisture exists but is retained in an aeriform condition by the radiating character of the soil, or carried away by the wind, it may be precipitated and rendered applicable to the uses of agriculture by the judicious planting of trees; while it is equally true that there are other localities in which the necessary water for vegetation can never be procured by artificial means. The necessary data for the investigation of this question in relation to the western portion of the great valley of the Mississippi can only be obtained by extensive series of observations on the relative humidity and the direction of the moisture-bearing winds of different portions of the country.

During the past year a self-registering barometrical apparatus, invented by Professor George W. Hough, of the Dudley Observatory, has been erected in the Institution, but owing to the position in which it was first placed the series of records has not been continuous, though from the records which have been obtained it would appear that the instrument is capable of giving valuable results. This instrument consists of an iron tube in the form of a siphon closed at the upper end and filled with mercury, and two cylinders or drums moved by clock work, to the surface of which is attached the paper receiving the register. On the surface of the mercury, in the shorter leg of the siphon, is an ivory float, fastened by a fine thread to one end of a lever, the other end of which terminates between two points connecting the opposite poles of a galvanic battery. As soon as the mercury begins to rise and while it continues to ascend, the end of the lever is pressed against the upper point, thus completing the circuit of an electro-magnet, which unlocks