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14. The Secretary, by the law of Congress, is alone responsible to the Regents. He shall take charge of the building and property, keep a record of proceedings, discharge the duties of librarian and keeper of the museum, and may, with the consent of the Regents, employ assistants.

15. The Secretary and his assistants, during the session of Congress, will be required to illustrate new discoveries in science, and to exhibit new objects of art; distinguished individuals should also be invited to give lectures on subjects of general interest.

This programme, which was at first adopted provisionally, has become the settled policy of the Institution. The only material change is that expressed by the following resolutions, adopted January 15, 1855, viz:

Resolved, That the 7th resolution passed by the Board of Regents, on the 26th of January, 1847, requiring an equal division of the income between the active operations and the museum and library, when the buildings are completed, be, and it is hereby, repealed.

Resolved, That hereafter the annual appropriations shall be apportioned specifically among the different objects and operations of the Institution, in such manner as may, in the judgment of the Regents, be necessary and proper for each, according to its intrinsic importance, and a compliance in good faith with the law.

REPORT OF THE SECRETARY.

To the Board of Regents:

GENTLEMEN: I have the honor to present, at the commencement of another session of your honorable board, the annual report of the condition and transactions of the Smithsonian Institution during the year 1863.

The general operations of the Institution are so uniform from year to year that the several annual reports can differ but little from each other; the usual order will, therefore, be observed in this communication, with only such variations as the special incidents of the year may require.

It will be seen by the report of the Executive Committee that the finances of the Institution are in as favorable a condition as the state of public affairs would authorize us to expect. First. The whole amount of money originally derived from the bequest of Smithson is still in the treasury of the United States, bearing interest at six per cent., paid semi-annually, and yielding $30,910. Second. Seventyfive thousand dollars of an extra fund are in bonds of the State of Indiana, at five per cent. interest, also paid semi-annually, yielding $3,750. Third. Fifty-three thousand five hundred dollars of the same fund are in bonds of the State of Virginia, twelve thousand in those of Tennessee, and five hundred in those of Georgia, from which nothing has been derived since the commencement of the war. Fourth. A balance of upwards of $32,000 is now in the hands of the treasurer of the Institution.

The unsettled accounts at the close of the year do not exceed two thousand dollars.

From this statement it appears that the Institution, after erecting a building, accumulating a large library and an extensive museum, supplying the principal museums of the world with specimens of natural history, and publishing a series of volumes which have been distributed to all first-class libraries abroad, and still more extensively at home, has upwards of one hundred thousand dollars in addition to the money received from the original bequest. In addition to this, the stocks of Virginia and Tennessee are quoted at about half

paper, by S. Weir Mitchell, M. D., and George R. Morehouse, M.D., of Philadelphia, is a very complete study of the anatomy and physiology of the breathing organs in turtles. It seems that, although at one time, and by a single observer, the true mode of the breathing of these animals was partially understood, it had long been neglected, and modern physiologists have taught that turtles forced air into the lungs as do frogs. Drs. Mitchell and Morehouse have shown that turtles breathe like mammals, by drawing air into the lungs by the aid of muscles situated in the flanks and on the outside of the lungs. Their paper contains a detailed account of the anatomy of the breathing organs of turtles, and is illustrated with numerous wood-cuts. The most novel discovery described by the authors is that of a chiasm or crossing from side to side of a portion of the nerves which supply the muscles of the larynx. Except the well-known facts as to similar crossings within the skull, no previous author has described any similar extra-cranial arrangement of nerves. The physiological uses of the laryngeal chiasm has been fully studied by Drs. Mitchell and Morehouse; and more recently Professor Wyman, led by their discovery, has described similar nerve arrangements in serpents and in certain birds.

The authors express their indebtedness to the Smithsonian Institution for the aid with which they were furnished in obtaining the requisite specimens for experiments and for dissection.

The following papers have been accepted for publication, and will form parts of the fourteenth volume of Contributions :

1st. Three additional parts of the series of discussion of the magnetic observations at Girard College, by Professor A. D. Bache.

2d. The result of a series of microscopical studies of the medulla oblongata, or the upper portion of the spinal marrow, by Dr. John Dean.

3d. A memoir on the paleontology of the Upper Missouri, by F. B. Meek and F. V. Hayden.

4th. An account of the photographical observatory and various experiments in regard to this subject, by Dr. Henry Draper, of New York.

5th. A monograph of the "Larida" or gulls, by Dr. Elliott Coues. All these memoirs, except the last, are in the hands of the printer, or in process of illustration by the engraver.

In several of the preceding reports an account has been given of a series of reductions of the magnetic observations made from 1840 to 1845, inclusive, at Girard College, Philadelphia, by Professor Bache.

The first two of the papers of this series related to what is called the eleven-year period of the variation of the needle, which corresponds with the recurrence and frequency of the spots on the sun. The third paper relates to the influence of the moon on the variation of the needle. The fourth refers to the change in the horizontal part of the force of the earth's magnetism coinciding with the elevenyear period of the spots on the sun. The fifth relates to the effect of the sun in producing daily and annual variations in the horizontal component of the magnetic force. The sixth relates to the lunar influence on the horizontal magnetic force.

A particular account has been given of the result of all these investigations, which tend fully to corroborate the conclusions arrived at from observations in other parts of the world, that both the sun and moon are magnetic bodies, and exert an influence upon the polarity of the earth; and also that the magnetism of the sun has variations. in intensity which are in some way connected with the appearance of spots on its surface, giving rise to the variations in those perturbations of the needle which have been called magnetic storms, and which present a periodical recurrence at an interval of about eleven years.

The influence of the moon is much less marked than that of the sun, and appears to be more analogous to the temporary magnetism induced in soft iron.

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Parts VII, VIII, and IX of this series, now in the press, are a continuation of the same subject. Part VII contains the discussion of the effect of a change of temperature on the readings of the vertical force instrument.

If a magnetic needle could be supported perfectly free in space, so as to assume the direction into which it would be brought by the magnetic action of the earth, it would arrange itself in the line of what is called the dip, or the inclination of the needle. At the magnetic equator of the earth such a needle would be parallel to the horizon, but, departing from this line either to the north or the south, the inclination would increase continually until we arrive at the magnetic pole, when it would be vertical. It is plain that the full magnetic force of the earth, in the line of the dip, may be resolved into two others, viz., a horizontal force, or that which draws the ordinary magnetic needle back to the meridian when it has been deflected from this position; and, second, the vertical force which tends to draw the end of the needle down into the line of the dip. The fre

quency of vibrations of a magnetic bar suspended by an untwisted thread, so as to be horizontal, gives the horizontal component of the force of the earth, while the vibrations of a similar bar placed in the plane of the dip, and poised horizontally like a scale-beam on two knite-edges, gives the variations in the vertical force. These vibrations, however, will be affected not only by the changes in the magnetism of the earth, but by that in the bar itself; and as the latter is affected by the temperature of the place, a series of observations and discussions was necessary to ascertain the corrections due to this cause. For this purpose the room was artificially heated and cooled; but the value of the correction was finally deduced from an investigation of the whole series of regular observations compared with the changes of temperature indicated by the hourly register of the thermometer.

The corrections for temperature were afterwards applied to all the observations. The larger disturbances were then separated from the body of the series in the same manner as had been done with regard to the horizontal force, by which means the effect of the monthly and yearly disturbance of the sun is exhibited analytically and graphically. From the results it appears that the number and aggregate amount of disturbances were least in 1844; that in each year the greatest number of disturbances occurs in March and September, and the least number in June, or, in other words, the maximum about the equinoxes, and the minimum about the solstices.

In an appendix to this paper the connexion of the appearance of the aurora borealis with the disturbances of the direction and force of the earth's magnetism is discussed. From the result of this discussion it appears that there is a periodicity of about eleven years in the recurrence of the frequency of the aurora, as well as in that of the great disturbances of the needle, and that these are coincident with each other and with the appearance of the spots on the sun.

The eighth part of the series gives the discussion of the daily and yearly variations due to the action of the sun on the vertical component of the magnetic force. The mean variation of the force is determined for each hour during each month and for the whole year, and also for the summer and the winter separately. These are expressed analytically and graphically, and an examination of the curve shows a principal maximum about 1 p. m., and a principal minimum about 9 a. m. There is an indication of a secondary maximum about 2 a. m., and a secondary minimum about 4 a. m.

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