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20. Nary bunting.

Exhibited is a piece each of red, white, and blue bunting, 18 inches in width manufactured expressly for use in the U. S. Navy, by the U. S. Bunting Company, in Lowell, Mass.

21. Flag of Fort McHenry, Baltimore, Md., in 1814.

This flag, seen by Francis Scott Key, of Baltimore, Md., flying from the flag-staff at Fort McHenry, in the early morning after the bombardment in 1814, inspired him to write the beautiful patriotie song Star-spangled Banner."

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THE STAR-SPANGLED BANNER.

BY FRANCIS SCOTT KEY.

OF BALTIMORE, MD., 1814.*

Oh! say, can you see, by the dawn's early light,

What so proudly we hailed at the twilight's last gleaming,

Whose broad stripes and bright stars through the clouds of the fight,

O'er the ramparts we watched, were so gallantly streaming?

And the rockets' red glare, the bombs bursting in air,

Gave proof through the night that our flag was still there :
Oh! say, does that Star-spangled Banner yet wave
O'er the land of the free and the home of the brave?

On the shore dimly seen through the mists of the deep,
Where the foe's haughty host in dread silence reposes,
What is that which the breeze, o'er the towering steep,
As it fitfully blows, half conceals, half discloses ?
Now it catches the gleam of the morning's first beam,
In full glory reflected, now shines on the stream.

'Tis the Star-spangled Banner! Oh! long may it wave
O'er the land of the free and the home of the brave.

And where is the foe that so sweepingly swore

That the havoc of war and the battle's confusion
A home and a country should leave us no more ?
This blood has washed out his foul footstep's pollution.
No refuge could save the hireling and slave
From the terrors of flight or the gloom of the grave;
And the Star-spangled Banner in triumph doth wave
O'er the land of the free and the home of the brave.

Oh! thus be it ever when foeman shall stand

Between their loved homes and war's desolation!

Blest with victory and peace, may the Heav'n-rescued land
Praise the Power that hath made and preserved us a nation.

Then conquer we must, when our cause it is just,

And this be our motto, "In God is our trust."

And the Star-spangled Banner in triumph shall wave

O'er the land of the free and the home of the brave.

22. Apparatus for determining personal equations in astronomical observations.

To determine the absolute, as well as the relative, personal equation of observers with the transit instrument. This apparatus requires simply a chronograph, with a single pen to record its own indications and the work of the observer; and it may then

*This is the version furnished by the author in 1842.

be employed to determine the personal equation of an observer using the eye and ear method, as well as the chronographic.

A similar apparatus has been in use at the United States Naval Observatory since April, 1875.

23. United States Transit of Venus Expeditions.

For the observation of the transit of Venus in December, 1874, the "United States Transit of Venus Commission" caused eight sets of instruments to be made, in all respects identical with each other, which were used respectively at Wladivostock, Siberia; Peking, China; Nagasaki, Japan; Kerguelen Island; Hobart Town and Campbell Town, Tasmania; Queenstown, New Zealand; and Chatham Island.

The set exhibited is the one which was used at Queenstown. The instruments are mounted in three portable observatories, so constructed as to be easily taken dowu and erected again; and everything is arranged precisely as it was when in actual use. The transit house is 2.44 meters long by 3.05 meters wide, and contains the following instruments, namely:

A meridian instrument arranged for the determination of time and latitude. Its telescope is of the diagonal form (that is, the eye-piece is at one end of the axis), has a focal distance of 762 millimeters, a clear aperture of 63.5 millimeters, and is provided with magnifying powers of 30, 60, and 90 diameters. The Ys are segments of cylinders, ground to fit the pivots accurately, and incapable of any adjustment. The adjustment for level is effected by means of the foot-screws of the substand, which are provided with heavy jam-nuts to fix them securely when they are properly set. To permit the use of the instrument in the vertical of the Pole-star, the azimuth adjustment has a range of more than five degrees. It is effected by means of abutting screws which move the stand upon the substand. The instrument is provided with suitable reversing apparatus, and with striding and hanging levels, the latter of which may remain upon the pivots at all times. A fine level, capable of rotating in the vertical plane, is attached to the tube of the telescope. and this, when used in connection with the zenith-distance micrometer of the eye-piece, converts the instrum nt into a zenith-telescope capable of determining the latitude with great accu

racy.

A chronograph for recording electrically the times of transits of stars observed with the meridian instrument, and the exact instant at which plates are exposed in the photographic telescope. This apparatus consists of a cylinder moved by clock-work, turning once in a minute, and covered with paper upon which the record is made by a pen actuated by an electro-magnet. The cylinder is large enough to contain two hours' work, each second being represented by a space millimeters long.

A dip circle provided with needles 127 millimeters long, for determining both the magnetic inclination, and, by Lloyd's method, the relative magnetic intensity.

A portable declinometer for determining the declination and absolute intensity of the earth's magnetism.

A universal instrument, having horizontal and vertical circles 76 millimeters in diameter, used with the portable declinometer, and also in setting up the observatory buildings.

A Y level, whose bubble will indicate half a second of arc, used for determining the constants of the photographic telescope.

A set of apparatus for the telegraphic determination of differences of longitude, consisting of a receiving magnet, sounder, transmitting key, and the necessary switches, the whole permanently arranged upon a suitable base. It is used in connection with the chronograph, which is specially fitted for longitude work.

The astronomical clock and break circuit chronometers, used with the meridian instrument, have, for convenience, been mounted inside the Government building.

The photographic house, 3.66 meters long by 3.05 meters wide, stands due south of the transit house, and is fitted with the baths, chemicals, water-tank, sinks, &c., used in photography. From the northern side of this house projects the

Photographic telescope employed in taking pictures of the sun. This instrument has an objective of 12.0 meters focus and 127 millimeters clear aperture, corrected for the chemical rays. An iron pier, standing between the transit and photographic houses, carries this objective, together with the heliostat which reflects the sun's rays into it. The sensitive plate, upon which the sun's image is formed, is mounted upon a second iron pier inside the photographic house. The slide for exposing the plate is connected telegraphically to the chronograph in the transit house. A standard iron rod, suitably mounted, serves for measuring accurately the distance between the objective and the sensitive plate.

The equatorial house is 3.05 meters in diameter, octagonal in form, and surmounted by a revolving roof. In it is placed

An achromatic refracting telescope of 1.778 meters focus and 127 millimeters clear aperture. It is mounted upon a portable equatorial stand, adjustable to any latitude whatever, from the north pole to the south pole, and provided with clock-work and divided circles. It has also a large finder, the usual battery of eye-pieces, and a double-image position micrometer.

24. W. M. Wood's apparatus for attaching, detaching, lowering, hoisting, and securing ships' boats.

The boat being secured for sea, and it becoming necessary in case of emergency, as a man overboard," or other causes, to place the boat quickly in the water, and clear the ship, it is only necessary to turn back the large screw which holds the cradle under the bottom of the boat, and thus allow it to drop clear; then the pendants from the inner arms of the davits are slacked, and the boat allowed to swing out, until it hangs directly from the outer arms of the davits. (It is understood that the boat has been manned by the crew.) When in this position, the boat's descent is controlled completely by one man, who is stationed at the compressing lever of the friction band. He first heaves this taut, and, placing his foot on the tail of the ratchet pawl, lifts it clear, when, by slackening slightly his friction band, he can lower as rapidly as he pleases, or check it up in an instant. As soon as the boat is manned, the stroke oarsfan casts off the trigger line, which is kept hitched forward as a safety lashing, and hands it to the coxswain; when the latter deems the boat low enough, he frees the ends of the connecting rope or chain from each other by a quick jerk on the trigger line. This allows the links in the ends of the boat to rise, and the ball toggles are released, and both ends of the boat are simultaneously detached. Immediately after detaching, the stroke oarsman should bring the ends of the rope together again, and set up the ship hook, which renders the boat ready for hooking on again when she returns. To hook on, it is only necessary to push the ball toggles into the links and pop in the counter-balanced tumblers, whose office is to prevent unhooking, when once hooked, by the motion of the boat. To hoist the boat, the men run away with the single rope on the large drum which winds up the wire-fall of the boat. When the boat is up, this drum is detached from its axle by withdrawing the linchpin, and the rope recoiled on it for future use and to get it off the deck. The pendants are then rove off, and the main fall slacked, which allows the boat to swing between the davits; the cradle is then lifted under it and secured. As a further securing, a line is taken over the in-board gunwale under a thwart, and back to the rail which steadies the oat in-board.

25. T.sts of iron.

Extracts from "Organization of the United States Board appointed to test iron,

steel," &c.

[This Board is appointed by the President of the United States, and instructed to determine by actual tests the strength and value of all kinds of iron, steel, and other metals which may be submitted to it, or by it procured, and to prepare tables which will exhibit the strength and value of said materials for constructive purposes.]

COMMITTEES.

(D.) On Chains and Wire Ropes: Commander L. A. Beardslee, U. S. N., chairman; Lieut. Col. Q. A. Gilmore, U. S. A.; Chief Engineer D. Smith, U. S. N.

Instructions. To determine the character of iron best adapted for chain cables, the best form and proportions of link, and the qualities of metal used in the manufact ure of iron and steel wire rope.

(E.) On Corrosion of Metals: W. S. Smith, C. E., chairman; Lieut. Col. Q. A. Gilmore, U. S. A.; Commander L. A. Beardslee, U. S. N.

Instructions. To investigate the subject of the corrosion of metals under the conditions of actual use.

(F.) On the Effects of Temperature: R. H. Thurston, C. E., chairman; Lieut. Col. Q. A. Gilmore, U. S. A.; Commander L. A. Beardslee, U. S. N.

Instructions. To investigate the effects of variations of temperature upon the strength and other qualities of iron, steel, and other metals.

(H.) On Iron, malleable: Commander L. A. Beardslee, U. S. N., chairman; W. S. Smith, C. E.; A. L. Holly, C. E.

Instructions. To examine and report upon the mechanical and physical proportions of wrought iron.

(J.) On Metallic Alloys: R. H. Thurston, C. E., chairman; Commander L. A Beardslee, U. S. N.; Chief Engineer D. Smith, U. S. N.

Instructions.

To assume charge of a series of experiments on the characteristics of alloys, and an investigation of the laws of combination.

(K.) On Orthogonal Simultaneous Strains: W. S. Smith, C. E., chairman; Commander L. A. Beardslee, U. S. N.; R. H. Thurston, C. E.

Instructions.—To plan and conduct a series of experiments on simultaneous orthogonal strains, with a view to the determination of laws.

(M.) On Reheating and Rerolling: Commander L. A. Beardslee, U. S. N., chairman; Chief Engineer D. Smith, U. S. N.; W. S. Smith, C. E.

Instructions. To observe and experiment upon the effects of reheating, rerolling, or otherwise reworking; of hammering, as compared with rolling, and of annealing the metals.

(0.) On Steel for Tools: Chief Engineer D. Smith, U. S. N., chairman; Commander L A. Beardslee, U. S. N., ; W. S. Smith, C. E.

Instructions. To determine the constitution and characteristics and the special adaptations of steels used for tools.

[Extracts from American Society of Civil Engineers, 4 East Twenty-third street, New York.]

TESTS OF AMERICAN IRON AND STEEL.

The committee on chains and wire rope is endeavoring to determine the character · of metal best adapted to making chain and rope, and the proper form and proportions of link, and is working up the data which have long been collecting at the Navy Department. The later experiments of Commander Beardslee are extensive in range, and that officer is collating and arranging the records for the use of the Board. Further experiment will fill up any hiatus that may be detected. The navy-yard at Washington, where this work is going on, affords peculiar facilities not only for testing but for making chain-cable of any desired size, form of link, or quality of metal. Work already done there by the chairman of this committee has revealed serious defects in accepted tables of sizes and strength, and has indicated the rate of variation of strength with variation of size of bar, and permitted the formation of a new and trustworthy table.

The committee on malleable iron has collated a large mass of valuable information and the records of a great number of experiments, and, among other important matter, has obtained an extensive collection of experimental determinations of the effect of time upon the elevation of the elastic limit by strain, during periods varying from a few seconds up to a year. The variation of quality due to differences of size and

form of section of the bar, and the modification of strength, ductility, and resilience, are under investigation. The chairman of this committee is also determining the influence of proportions of test-pieces upon their ultimate resistances.

The committee on reheating and rerolling is to test iron, &c., in the several stages of manufacture, refined and unrefined, and to observe the effects of successive reheats, of reworking and rolling, to determine, if possible, what amount of working is demanded by different irons, and what are the temperatures which will practically give the best results.

The committee on steel for tools is making an extended series of experiments at the Washington navy-yard to determine the value of various steels for tools. A large collection of steels is made; their composition is determined, and they are then carefully tested by setting them at work-turning, planing, boring, and chiseling—and their behavior and their composition being thus ascertained, it will probably be easy to learn the chemical and physical characteristics of the best tool. The names of makers are of no importance in this investigation, and are not to be reported. The Board, in all its work, will avoid reference to makers of material in any way that may injure any manufacturer directly or indirectly. Scientific knowledge of directly practical value, and engineering facts and figures, solely are sought.

PROPORTIONS OF TEST-PIECES. PEMBROKE RIVET 2 INCH.

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MEMORANDUM OF TESTS OF FOUR SAMPLES MADE FROM 2-INCH CATASAUQUA BAR

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of square bars welded together.

The fractured ends of the samples show small squares, as if the iron had been made

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