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north, Lon. 71° west. north, Lon. 6° west. north, Lon. 9° west. north, Lon. 75° west.

Lat. 34° south, Lon. 18° east. Lat. 41° north, Lon. 72° west. Lat. 39° north, Lon. 75° west. Lat. 32° north, Lon. 81° west. EM 4.. To find all those places that are in the same latitude de as a given place.

- Bring the given place to the brass meridian; then all the der the meridian have the same longitude; turn the globe all places which pass under the latitude of the place have latitude.

nat places have nearly the same longitude as New York? pany, Montreal, Bogota.

nat places are in the same latitude?

ton, Madrid, Naples, Constantinople.

hat places have the same longitude and latitude as the fol

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Q. What is the difference of latitude between Washington a Cape Horn?

Sum 93°.

A. Washington 37° north, Cape Horn, 56° south.
Q. Find the difference of latitude between the following places:-
New Orleans and Quebec,
Mexico and Rio Janeiro,
Madrid and Cairo,
Pekin and Botany Bay,

St. Petersburgh and Rome, PROBLEM 6. To find the

places.

Cape of Good Hope and Cape Hor difference of longitude between any tu

RULE. Find the longitude of each place, and note them down then, if both places are east or west of the meridian, subtract the le longitude from the greater; but if one is east and the other west, ad the longitudes.

Q. What is the difference of longitude between New York an New Orleans?

A. New York 74°; New Orleans 90° west- difference 16 degrees Q. What is the difference in longitude between Boston and Rome A. Boston 71° west; Rome 12° east-sum, 83 degrees.

If the sum of the longitudes exceed 180 degrees, subtract it fron 360 degrees; the remainder will be the difference in longitude; as Astoria 124° west; Pekin 116° east 240: 360-240-120° differ ence in longitude.

PROBLEM 7. The hour of the day at any place being given, to find what o'clock it is at any other place.

RULE. - Bring the place at which the time is given to the brass meridian; set the index to the given hour, then turn the globe till the proposed place comes to the meridian; the index will point to the hour required. If the place required is east of the given place, it is later; if to the west, it is earlier.

Q. When it is noon at New York, what is the time in London ? A. 4 o'clock 56 min.

Q. When it is noon at Washington, what is the hour a Boston, New Orleans, Mexico, Quebec, Aoria, Pekin, Cape Horn, Rome, St. Petersburgh, Moscow Canton, Dublin? When it is midnight at New York, what is the hour at Paris, Cairo, Calcutta, St. Helena, Gibraltar, Havana, Nankin, Tunis, Cadiz ? Constantinople, Mexico, Astoria, PROBLEM 8.- The hour of the day being given at any place, to find all places on the globe where it is then noon, or any other given hour. RULE. Bring the place to the brass meridian; set the index to the hour of that place; turn the globe till the index points to the other given hour; then all places under the brass meridian will be the places required.

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RULE. Bring the place to the brass meridian, and find its latitude; set the index to twelve, and turn the globe till the index points to the other twelve; then, under the same degree of latitude, on the other side of the equator, will be the Antipodes.

-

PROBLEM 12. To find the distance in miles between any two places on the globe.

RULE. Lay the quadrant of altitude over the two places, so that the division marked 0 will be on one of the places, and it will show the number of degrees between them; which, multiplied by 69, will give the distance in miles.

PROBLEM 13. To find the Sun's Longitude or place in the Ecliptic and his declination. in any given month or day.

.LLUSTRATED ASTRONOMY.

RULE.-Look for the given day in the circle of nonths on the wooden horizon, and opposite to it, in the circle of signs, are the sign and degree in which the sun is for that day. Find the same sign and degree in the ecliptic on the surface of the globe; bring the degree of the ecliptic, thus found, to the brass meridian, and the degree of the meridian will be the declination.

PROBLEM 14.-To find the time at which the Sun rises and sets at any place, the day in the year, and the length of the day and night at that place.

RULE.-Raise the pole (of the hemisphere in which the place is situated) as many degrees above the horizon as are equal to the latitude of the place; bring the sun's place on the given day, to the meridian, and set the index to 12: bring the sun's place to the eastern horizon, and the index will show the time of the sun's rising; bring the sun's place to the western edge of the horizon, and the index will show the hour of setting. Double the time of the sun's setting, and the length of the day will be had; double the time of the sun's rising, and the length of the night will be had.

PROBLEM 15.-To find the length of the longest and shortest days and nights at any place on the earth.

RULE. If the place is in the northern hemisphere, elevate the north

pole till the horizon cuts the brass meridian
ing to the latitude of the place; bring the firs
meridian, and set the index to 12; find the
(by problem 13,) and bring it to the eastern
the index will show the hour of the sun's ris
it will give the length of the longest night.
the western edge of the horizon, and the ind
setting, double this time, and you will have
day at that place. If the place is in the sou
the south pole to correspond with the latitud
first degree of Capricorn to the meridian, and
Q. What is the length of the longest day
York?

A. Longest day, 14 h. 56 min.; shortest PROBLEM 16.-To find those places where on a given day.

RULE. Find the sun's declination on the raise the pole (nearest to the sun's place,) a horizon as are equal to the declination; tur axis, and at all places that do not come above not rise on that day; and at all places arou not pass below the horizon, the sun does not

PROBLEMS PERFORMED WITH THE CELESTIAL GLOBE.

[Latitude, on the Celestial Globe, is reckoned 90°, either north or south, on circles of Celestial Latitude, which are at right angles to the ecliptic. (SEE DIAGRAM, page 55.)

Longitude, on the Celestial Globe, is reckoned on the ecliptic, from the first degree of ARIES, eastward, round the globe.

Declination, is reckoned from the equinoctial, either north or

south.

Right Ascension, is reckoned, on the equinoctial, from the first degree in ARIES, eastward, round the globe.]

PROBLEM 1.-To find the Right Ascension and Declination of the Sun or a Star.

RULE.-Bring the sun or star to that part of the brass meridian which is numbered from the equinoctial towards the poles: the degree on the brass meridian, over the place, will show the declination; and the number of degrees on the equinoctial, between the brass meridian end the first point of Aries, is the right ascension.

Required the right ascension and declination of the following stars:
Aldebaran, in Taurus,

Sirius, in the Great Dog,
Vega, in the Harp,

Arcturus, in Bootes,
Capella, in Auriga,
Regulus, in Leo.

PROBLEM 2.-To find the Latitude and Longitude of a Star. RULE.-Place the end of the quadrant of altitude, which is marked 90°, on the north or south pole of the ecliptic, according as the star is north or south of the ecliptic; then move the other end till the graduated edge of the quadrant comes to the star. The number of degrees on the quadrant, between the ecliptic and the star, is the latitude; and the number of degrees on the ecliptic, reckoned eastward, from the first point of Aries to the quadrant, is the longitude.

EXAMPLE.-Required, the latitudes and longitudes of the following

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Q. What stars have the following right as

Right Ascension.

76° 14'

Declination.
8° 27' S.

Right A

86°

83 6

34 11 S.

99

19

50 N. 23 29 N.

11

46

25 54
53 54

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PROBLEM 5.-The latitude of a place, the to place the globe in such a manner as to re time, in order to point out the situations of the able stars.

RULE.-Elevate the pole for the latitude globe due north and south by a meridian lin he ecliptic, bring it to the brass meridian, a the time be afternoon, turn the globe westwa the globe eastward, till the index points to face of the globe then represents the appeara time and place.

PROBLEM 6.-To find the distance of the degrees.

RULE.-Lay the quadrant of altitude over division marked 0 may be on one of the st them will show their distance, or the angle as seen from the earth.

EXAMPLE. What is the distance, in degi Vega and Altair? Ans. 34 degrees. Regulus and Procyon, Aldebaran and Sirius,

Also, between

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ILLUSTRATED ASTRONOMY.

GLOSSARY,

OR EXPLANATION OF ASTRONOMICAL TERMS.

-An aparent annual motion in the fixed stars, occasioned by the velocity of the real velocity of the earth in its orbit.

Substances either solid, liquid, or fluid, which imbibe the rays of light and heat. ncrease in the rapidity of the motion of a moving body. The motions of the ed from their aphelion to their perihelion

is said to rise or to set acronycally when it rises or sets at the instant of sunset. the form of air.

ic stone.

-A transparent, invisible, elastic fluid, surrounding the earth, in which we

ght of an object above the horizon.

e applied to the inhabitants of the torrid zone, because within the year, their e cast both north and south.

istance which a heavenly body rises from the east, or sets from the west point

re on the artificial globe, drawn from one tropic to the other, on which is lination for each day in the year.

r or opening between two lines that meet. A right angle contains 90 degrees, line falling perpendicularly upon another. An acute or sharp angle is less An obtuse or blunt angle is greater than a right angle. The measure of an

C.

fa Double Star.-The angle which a line joining the two stars makes with eridian.

-The distance between two objects, which is indicated by the angle, made by to them from a given point.

-A periodical inequality in the motion of the moon, or a planet, going through

of the Earth.-Its yearly revolution round the sun.

the form of a ring.

's angular distance from the apogee, or the earth's from aphelion.

A circle round the south pole, 23° 28′ from it.

who live on directly opposite sides of the earth.

no live in equal latitude on directly opposite sides of the equator.

nt in a planet's orbit which is farthest from the sun.

t of the orbit of the moon or a planet farthest from the earth.

The diameter of a body as seen from the earth.

The motion of the heavenly bodies as viewed from the earth.

The time shown by the sun, as indicated by a dial.

of an orbit which is at the greatest or least distance from the centre of motion. the higher apsis; the latter the lower apsis. The two together are termed the iting them is called the apsis line, or line of the apsides.

eventh sign of the ecliptic.

he circumference of a circle.

ircle round the north pole, 23° 29′ from it.

ny, they are the spaces passed over by the radius vector of a celestial body.

gn of the ecliptic. Its first point is at the vernal equinox.
tity by which another quantity or equation is found.
nce. The difference between right and oblique ascension.

arance of the heavenly bodies with respect to position, angular distance, &c. mall primary planets, whose orbits are between those of Mars and Jupiter. a. Astræa, Juno, Ceres, Pallas, Hebe, Iris and Flora. Some suppose them to let, burst by some internal explosion.

-Time reckoned from the noon of one day up to 24 hours, to the noon of sequently is made up of the last 12 hours of the same civil day, and the first ivil day.

ir that surrounds the earth.

wer of one body to draw another towards it.

ing, or the morning twilight.

· Northern Lights.-A luminous appearance .n the heavens, usually seen in named from its frequent resemblance to the morning dawn.

The line around which a revolving body turns.

-The major axis is the greatest diameter. The minor axis is the least

ance of a heavenly body east or west of the meridian, which is indicated by

> meridian and the vertical circle passing through the body.

1 Circle -A great circle in the heavens, passing through the zenith and nadir, n at right angles.

ars. Two stars revolving about each other.

"ear. Every fourth year, in which February has 29 days.

y this term is applied to any one of the celestial orbs.

ippled to the Almanac, or the divisions of time of which it treats.

The months as laid down in the almanac.

1 sign of the ecliptic.

ath sign of the ecliptic.

he east, west, north and south points of the horizon.

The force which urges a revolving body forward in its orbit, o tends to centre of motion.

The force which draws a revolving body towards the centre of motion. ine from one end of an arc to the other.

unded by a curve line, every part of which is equally distant from the cenone whose plane divides a globe into two equal parts called hemispheres ; hose plane divides a globe into unequal parts.

-The circle where the plane of the meridian meets the heavens. -The circle that divides the enlightened from the dark hemisphere. boundary of a circle. The circumference of every circle is supposed to be parts, called degrees; each degree into 60 equal parts, called minutes; and ual parts, called seconds.

Those stars which revolve around the pole without passing below the the atmosphere, condensed into small drops of water, and thus rendered

meridians which pass through the equinoctial and solstitial points of the inoctial and solstitial colures.

a a luminous train or tail, moving around the sun in a very elongated orbit. cor Angle-What it wants of 90 degrees.

in a circular manner.

Circles having the same centre.

circular base, and tapering equally upwards to a point.

eavenly bodies are in conjunction when they have the same longitude. A junction when it is between the earth and sun: in superior conjunction when he inferior planets only have inferior conjunction, but all have superior con

ps of stars to which the names of men and animals were anciently given. ment is divided into such groups.

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Cycle of the Moon, or Metonic Cycle.-A period of 19 years; after which the changes of the moon return to the same days of the month (when five leap years are included,) as on the same year of the preceding cycle, or 19 years before.

Cycle of the Sun.-A period of 29 years; after which the same days of the month return to the same days of the week; and the sun's place, to the same degrees and minutes of the ecliptic, as on the same year of the preceding cycle.

Cycle of a Planet.-A period during which a planet passes through its various positions with respect to the sun and earth.

Cylinder.-A round figure or solid of equal size from end to end.

Cylindrical.-Having the form of a cylinder.

Declination. The angular distance of a heavenly body, north or south, from the equinoctial. Degree.-One 860th part of the circumference of a circle.

Diagonal.-A line drawn from corner to corner of a four sided figure.

Dial.-An instrument showing the hour of the day, by the shadow of the sun.

Diameter-A straight line passing through the centre of a figure, and terminated both ways by

its sides or surface. The longest and shortest diameters of an ellipse are called the transverse and conjugate diameters.

Dichotomized-Divided into equal and similar parts, as the disc of the moon at quadrature.
Digit.-One-twelfth part of the apparent diameter of the sun or moon

Direct motion of a Planet-Apparent motion from west to east, according to the order of the signs.
Disc.-The apparent surface of a heavenly body.

Diurnal Arc.-The arc described by a heavenly body from its rising to its setting.

Diurnal Revolution of the Earth.-Its daily rotation on its axis, from west to east.

Dominical Letter-The letter in the calendar against Sunday; the first 7 letters of the alphabet being applied to the first 7 days of the year.

Dionysian Period. —A period of 532 years; found by multiplying the cycles of the sun and moon.
Earth-The globe on which we live.

East. The direction in which the sun rises at the equinoxes.
Eccentric.--Deviating from the centre; irregular.

Ecccentric Circles.-Those that are wholly or partially included in each other, but have different

centres.

*

Eccentricity. The distance from the centre of an ellipse to either of its foci.
Ecliptic. The circle, where the plane of the earth's orbit meets the heavens.
Egress.-The act of going out

Element. Fundamental principle; quantity by which something else is found.
Elevation-Height or altitude

Ellipse-An oval; a figure made by the oblique section of a cone.

Elongation-The angular distance of a planet from the sun, or the difference of their celestial longitude.

Emersion. The act of rising out of something, or re-appearing.

Epact. The age of the moon at the commencement of the year.

Epicycle.-The curve described by a point of one circle, revolving upon another circle

Epoch or Era.-A particular time, from which events are reckoned.

Equation. A quantity to be applied to mean time, place, or motion, in order to find the true. Equator. A great circle, whose plane is perpendicular to the earth's axis.

Equinoctial or Celestial Equator.-The circle, where the plane of the equator meets the heavens. Equinoctial Points.--The points where the equinoctial cuts the ecliptic, or the first points of Aries and Libra.

Equinoz-The time when the sun enters either of the equinoctial points. The vernal equinox occurs in March, the autumnal in September.

Evection-A periodic inequality in the motion of the moon.

Firmament. The heavens, or orb of fixed stars.

Fixed Stars.-Those stars which preserve the same situation with respect to each other.
Foci.-The plural of focus; the two points round which an ellipse is drawn.

Fogs or Mist-Vapor, condensed into minute drops of water, as in clouds.

Frustum.-What remains of a regular figure after a piece is cut off by a plane parallel to its base. Galaxy or Milky Way.-A luminous zone in the heavens, composed of an immense number of

fixed stars

Geocentric. As seen from the earth, or the earth being the centre.

Gibbous-The shape of the illuminated part of the moon, when more than half and not the whole of its disc is visible.

Globe. A sphere, ball, or round body. Artificial globes of two kinds are made; the terrestial, to represent the earth; and the celestial, to represent the heavens.

Golden Number-The number of years in the cycle of the moon since the epact was nothing Gravitation or Gravity -The attraction or power which draws ail bodies towards each other. Also, its effect, as weight, caused by the earth's attraction.

Hail.-Drops of rain, frozen while falling

Harvest Moon. The full moon nearest the autumnal equinox.

Heliacal. The heliacal rising or setting of a star takes place, when it rises a little before or sets a little after the sun.

Heliocentric. As seen from the sun, or the sun being the centre

Hemisphere.-Half a sphere or globe.

Heteroscii.-A name given to the inhabitants of the two temperate zones, because at noon those in the northern always have their shadows in an opposite direction to those in the southern. Horizon -The visible or sensible horizon is the circle where the sky and earth appear to meet. The rational horizon is parallel to the visible, and its plane divides the earth into upper and lower hemispheres. It is represented on the artificial globe by the wooden horizon. The circle where its plane meets the heavens is cailed the celestial horizon. Horizontal-Level or parallel to the horizon

Hour Circle.-A small circle, on the globe, near the north pole, having on it the hours of the day. Immersion.-The act of plunging into something, or disappearing.

Inclination-Angle. A position forming an acute angle.

Index.-A movable hand on the globe, to point out the time on the hour circle.

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ILLUSTRATED ASTRONOMY

79

GLOSSARY, OR EXPLANATION OF ASTRONOMICAL TERMS, (CONTINUED.)

in the Heavens.--The angular distance of a heavenly body, measured on the ecliptic m the first point of Aries.

-Capable of shining without light from another body.

ance. The angular distance of the centre of a celestial object from the centre of the

th. The time from one new moon to the next. -The average time of the lunar month.

Compass. An instrument with a magnetic needle, to point out the horizontal

e quantity of matter in a body.

erage; applied to distance, longitude, motion, place, time, &c.

f a Place. A great circle passing through the place and the poles of the earth. The n is the one from which longitude is reckoned. The brazen meridian is that in which globe turns.

A transitory object in the air. Falling stones are often called meteorites.

Dne 60th part of a degree; also one 60th part of an hour.

uthing-The time when the moon comes to the meridian of a place.

- point directly opposite to the zenith, or beyond the centre of the earth.
r.-The least flood and ebb tide.

Clus-ers of Stars, or other causes of the luminous appearances in the heavens.
Arc. The arc described by a heavenly body from its setting to its rising.

nal Degree. The highest point of the ecliptic above the horizon.

he point of the moon's or a planet's orbit that is cut by the plane of the ecliptic. There les, one on each side of the centre of motion; and a ine joining them is called the line The place where the body passes to the north of the ecliptic is called the ascending other the descending node.

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e. The reckoning of time established by Gregory XIII., and now generally adopted That point of the horizon which is directly towards the northern pole.

of a Comet. The part of its head which appears to be dense.

-A variation in the direction of the earth's axis, caused by the attraction of the moon uberant matter at the terrestrial equator.

-Forming an acute or obtuse angle; not perpendicular.

Ascension-That degree of the equinoctial which rises with a body in an oblique
Descension. That degree of the equinoctial which sets with a body in an oblique

y.-Deviation from parallelism and from perpendicularity

y of the Ecliptic.-The angle formed by the equinoctial with the plane of the ecliptic al-To the west, where the heavenly bodies appear to descend.

-ion.-The eclipse of a star or planet by the moon or by another planet.

-Forty-five degrees distant, or the eighth part of a circle.

-le-That reckoning of time which makes every fourth year a leap year.

-Not luminous or transparent.

on-Two bodies are in opposition when they are on opposite sides of the earth. The path in which one body moves round another.

-Towards the east, where the heavenly bodies rise.

-The difference of the place of a body, as seen from different points of view. Diurnal Es the difference between the apparent and true place of a body. Horizontal parallax is al parallax of a body in the horizon. Annual parallax is the difference of the apparent body, as seen from different parts of the earth's orbit.

etic Motion.-Angular motion sufficiently great to be perceived.

Lanes.-Those continued in the same direction, at the same distance from each other. of altitude, declination, and latitude, are small circles parallel to the horizon, equinoctial,

zor.

bra.-A partial or imperfect shadow.

The point nearest the earth, in the orbit of the moon or a planet. i-Those who live in equal latitude on opposite sides of the pole.

ion. The lower apsis, or point nearest the sun, in a planet's orbit.

Ec Inequality-An irregularity in the motion of celestial body, requiring a comparatively
e for its accomplishment.

Ec Time -The time in which a heavenly body revolves around its centre of motion.
i-A name given to the inhabitants of the frigid zone, because their shadows turn all
em in one day

dicular.-Making a right angle with some line or surface.

bations.-Irregularities in the motions of bodies, from some disturbing cause.
-Different appearances of the moon and planets as they are differently illuminated.
nena.-Appearances in the works of nature. (Singular Phenomenon.)
al.-Belonging to material nature.

-The 12th sign of the ecliptic.

-Length and breadth without thickness. The plane of a circle is the surface contained

, and continued out of it on all sides, indefinitely, to the heavens.

-An opake body revolving around the sun. The secondary planets revolve around the planets, as well as around the sun. Those planets nearer to the sun than the earth is, are ferior; those more distant are called superior.

tes.-The seven stars in the constellation Taurus.

-That which has position but no magnitude.

Circles. Small circles drawn around the poles, 231 degrees from them.
Distance.-Angular distance from the pole, measured on a circle of declination.

-The terrestrial poles are the extremities of the earth's axis. The celestial poles are the
where the earth's axis, if produced, would meet the heavens.

Star-A star of the second magnitude, near the north pole of the heavens.

ers-Two stars in the great bear, that serve to point out the pole star.

ssion of the Equinoxes.-A retrograde motion, on the ecliptic, of the equinoctial points,

by the action of the sun and moon upon the protuberant matter at the earth's equator rant.-Ninety degrees, or a quarter of a circle. An instrument to measure angles. rature. The position, a quarter of a circle from the sun.

vilateral Figure.-One that has four sides.

tile-Ninety degrees distant from each other

scent.-At rest; not in motion.

ation.-An emission of rays

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Satellite-A moon, or secondary planet.

Scorpio. The eighth sign of the ecliptic.

Secondary Circles.-Such as are in planes that are perpendicular to those circles of which they are the secondaries.

Sector of a Circle.-Space enclosed by two radii and an arc, less than a semicircle. Secular Inequalities. Variations in the motions of the heavenly bodies, requiring many ages for their accomplishment.

Segment. Any part of the surface of a circle cut off by a cord.

Semicircle.-Half a circle. Half of the circumference, or an arc of 180 degrees

Sidereal Day.-The time included between two consecutive transits of the same star at the same meridian. This period is invariably of exactly the same continuance; and it is the only one in nature, with which we are acquainted, that is so. Hence it forms a perfect standard measure, by reference to which all portions of time may be ascertained. Astronomical clocks are made to show sidereal time. It may likewise be observed that our standard measures of length, capacity, and weight, depend upon the equable rotation of the earth on its axis, as they are referred to the length of a pendulum beating seconds of mean time.

Sign-Thirty degrees, or the 12th part of a circle. The ascending signs of the ecliptic are those in which the sun's meridian altitude is daily increasing.

Snow-Water frozen while in the form of clouds, mist, or fine rain, which then falls gently to the earth.

Solar Day.-The time from one noon to the next, is the apparent, and the average time of that period, the mean, solar day

Solar System.-The sun, with its planets and comats arranged regularly, in their several positions. Solstices.-The times at which the sun is in the solstitial points. When the sun is at the summer solstice all places in the northern hemisphere have their longest day. These days vary in length from 12 hours at the equator to 24 at the arctic circle, and in the frigid zone they increase from 24 hours at the arctic circle to 6 months at the pole, where there is but one day and night during the year. At the same time ali places in the southern hemisphere have their shortest day, These vary from 12 hours at the equator to nothing at the antarctic circle, where the sun does not rise above the horizon. The length of the days in south latitude corresponds to the length of the nights in north latitude; and the length of the nights in south latitude corresponds to the length of the days in north latitude When the sun is at the winter solstice, this condition of things is reversed, and the southern hemisphere presents the same phenomena, with respect to the sun, as does the northern when the sun is at the summer solstice.

Solstitial Points.-The points of the ecliptic which are farthest from the equinoctial.
South. That point of the horizon which is directly opposite to the north pole.

Sphere. A globe or ball. A solid which has every point of its surface equally distant from its centre. Also, the concave expanse of the heavens that surrounds the earth. The sphere has three positions, right, oblique and parallel. Those who live at the equator have a right sphere, all the circles of daily motion rising directly above, and descending 'irectly below the horizon. Those who live between the equator and poles have an oblique sphere, all the circles of daily motion being oblique to the horizon. Were any one at either of the poles he would have a parallel sphere, all the circles of daily motion being parallel to the horizon On the artificial globe a right sphere is represented by placing both poles in the horizon; an oblique sphere by raising one pole a little and depressing the other; a parallel sphere, by bringing one pole to the zenith and the other to the

nadir.

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Spring Tide.-The greatest flood and ebb tide.

Stationary,-A term applied to the apparent motion of a planet, when its real motion, combined with that of the earth, causes it to remain at the same point in the heavens.

Supplement of an are or angle. What the arc or angle wants of 180 degrees.
Surface--That which has length and breadth, but no thickness.

Synodic Month-A complete unation, or from one new moon to another; it being 29 days, 19 hours and 44 minutes.

Syzygies.-The points in the moon's orbit where she is new or full.
Taurus-The second sign of the ecliptic.

Tide.-The rising and falling of the waters of the ocean. The rising of the water is called flood tide; the falling, ebb tide.

Transit-The passage of a body across the meridian of a place. The transit of Mercury and
Venus usually means their apparent passage across the sun's disc.
Trapezium-A figure bounded by four unequal sides.

Triangle.-A figure bounded by three lines, or sides. An equilateral triangle has three equal
sides; an isosceles, only two; a scalene triangle has three unequal sides. A triangle is called a
right, obtuse, or acute angled triangle, according as it has a right, obtuse, or three acute angles.
Tropic of Cancer.-A small circle, 23° 28′ north of the equator, and parallel to it.
Tropic of Capricorn.—A small circle, 23° 28' south of the equator, and parallel to it.
Tropical Year.-The period between the consecutive returns of the sun to the same tropic or
solstice.
True Distance.-The actual distance of a body from the sun, or of a satellite from its planet.
True Place of a Planet.-The place where it would appear to be, if seen from the centre of the
earth, or centre of motion.

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Twilight.-The faint light of the sun before sunrise and after sun-set.

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Vertical Circle-A circle in a vertical plane, passing through the zenith and nadir, and cutting the horizon at right angles.

Virgo-The 6th sign of the ecliptic.

Waning-Declining in power, or decreasing in light

West. That direction in which the sun sets when in the equinoxes.

Wind.-Air in motion. The trade winds blow steadily to the westward, in the Atlantic and Pacific oceans, between the tropics. The monsoons, or shifting trade winds, in the Indian ocean, blow part of the year one way, and the other part in an opposite direction. The winds beyond the 40th degree of latitude are all variable. In the torrid zone, near the sea, breezes blow from the land in the morning and from the sea in the evening.

Year-A solar or tropical year is the period from the departure of the sun from the summer solstice, to its return to it again." Its length is 365 days, 5 hours, and nearly 49 minutes. The sidereal year, which is the period between the departure and return of the sun to a fixed star, is about 17 minutes longer. The anomalistical year is the time from the sun's leaving his apogee till he returns to it, and is 365 days, 6 hours, and about 14 minutes. Zenith-The point in the heavens directly over head.

Zenith Distance.-The angular distance of a heavenly bod, from the zenith, measured on a verti

cal circle.

Zodiac.-A space or belt in the heavens, 16 degrees broad, on each side of the ecliptic,) in which are the orbits of all the planets except a part of the asteroids.

Zone.-A belt or girdle on the earth's surface, formed by circles parallel to the equator There are five zones; the torrid, two temperate, and two frigid, formed 'sy the tropics and polar circles

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roved. By ASA SMITH.

'S BOOK-KEEPING.

"S KEY TO BOOK-KEEPING.

'S BLANKS TO BOOK-KEEPING.

CK'S BOOK-KEEPING.

K'S KEY TO BOOK-KEEPING.

S SEQUEL TO ARITHMETIC.

FISK'S GREEK GRAMMAR.

FISK'S GREEK EXERCISES.

VALPEY'S GREEK DELECTUS.
GRAGLIA'S ITALIAN DICTIONARY.

NEUMAN AND BARETTI'S SPANISH AND ENGLISH DIC.
TIONARY.

MUSIC.

S ELEMENTARY ALGEBRA. BY THOMAS SHERWIN, A. M., EXCELSIOR SONG BOOK. By Professor B. F. BAKER. ncipal of the English High School, Boston.

S KEY TO ALGEBRA.

HILOSOPHY. With Frost's Questions.

ECTURES ON MODERN HISTORY.

PROGRESSIVE EXERCISES IN COMPOSITION.
SPEAKER. By HENRY B. MAGLATHLIN.

K OF PROSE AND POETRY. By RICHARD and ORCUTT.
URRAY'S GRAMMAR.

BOSTON SCHOOL DICTIONARY.

ASS BOOK OF ANATOMY.

5 FAMILIAR SCIENCE.

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Songs, Chants, and Hymns, designed for Juvenile Classes and Seminaries; con-
taining a Complete System of Elementary Instruction in the Principles of Mu-
A collection of
sical Notation. Just published.

SABBATH HARMONY. By L. O. EMERSON. A new collection of Sacred
Music, containing a Great Variety of Psalm and Hymn Tunes, Anthems,
Motets, Chants, &c. For the use of Choirs, Congregations, Singing Schools,
Musical Conventions, and the Home Circle.

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Hundred and Sixty New Interpretations, with Colored Plates, elegantly printed
on Tinted Paper.

AGE OF FABLE. By THOMAS BULFINCH, A. M. The most popular Book on
Mythology ever published.

POETRY OF THE AGE OF FABLE. In Press.

OCTAVO BIBLE. Boston Edition.

POCKET BIBLE. 32mo., Pearl, morocco, tuck.

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LADY'S ALMANAC.

PRIVATE HOURS. By MISS DIX.

HOYLE'S GAMES. 32mo.

HOYLE'S GAMES. 12mo.

BOHN'S HAND BOOK OF GAMES. 12mo.

PEOPLE'S LIBRARY EDITION.

COMMON SCHOOL ARITHMETIC.

"REATISE ON ALGEBRA.

CLEMENTARY GEOMETRY.

EY TO INTELLECTUAL ARITHMETIC.

WAVERLY NOVELS. 27 vols. Illustrated, black cloth.

66

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EY TO COMMON SCHOOL ARITHMETIC.
EY TO NATIONAL ARITHMETIC.

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half morocco. library style. folded.

EY TO ALGEBRA.

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