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Cephalopoda.-Belemnites acutus, compressus, etc.; Nautilus striatus, Sing. Soy hallado, I am found.
annularis, etc.; Ammonites planicostatus, margaritatus, aculeatus,
annulatus, bisulcatus, sulcatus, etc.
Gasteropoda.-Trochus imbricatus; Turbo capitaneus; Pleurotomaria

compressa.
Echinodermata.-Uraster Gaveyi; Aspidura loricata; Astropecten
arenicolus; Extracrinus briareus; Pentacrinus basaltiformis.
Crustacea.-Coleia antiqua; Glyphea liassina.
Insecta.-Berosus; Libellula dislocata.
Fish.-chmodus angulifer, speciosus, etc.; Acrodus nobilis; Eugna-
thus fasciculatus; Hybodus carinatus; Leptolepis caudalis;
Lepidotus fimbriatus.
Reptiles.-Ichthyosaurus, Plesiosaurus, Pterodactylus, Teleosaurus.

LESSONS IN SPANISH.-XIII.
REFLECTIVE VERBS.

THOSE verbs are called reflective or reciprocal which reflect the
action they express on their nominative; as, yo me desnudo, or
me desnudo, I undress myself; el se ahorcó, or se ahorcó, he
hung himself; nosotros nos amamos, we love ourselves, or we
love each other.

The reflective verbs are inflected in the same manner as the verb would be conjugated if it were employed without the reflective pronouns. The verb ahorcar is thus conjugated reflectively:

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A passive verb is conjugated by adding to the auxiliary verb ser, through all its moods and tenses, the past participle of the verb to be conjugated. The participle in such a case is inflected by gender and number like an adjective; thus to say, he is loved, she is loved, they are loved (masc.), they are loved (fem.), would be el es amado, ella es amada, ellos son amados, ellas son amadas.

The passive verb formed by ser is used in Spanish in the present and imperfect tenses of the indicative mood only when a mental act or state of the emotions is spoken of; thus we can say, ella es amada, she is loved; but we cannot say, ella es hallada, she is found; since, in the latter case, no state of mind or feelings is described, and the perfect indefinite tense must be employed; thus, ella ha sido hallada, she has been found. For the past tense of the indicative, when no state or act of the mind is spoken of, the perfect definite must be used; as, la casa fué (not era) quemada, the house was burnt.

The passive verb ser hallado is thus conjugated :—

Eres hallado.
Es hallado.

Plur. Somos hallados.

Sois hallados.
Son hallados.
Imperfect.

Sing. Era hallado, I was found.
Eras hallado.
Era hallado.

Plur. Eramos hallados.

Erais hallados.
Eran hallados.

Perfect Definite.

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Imperfect.

Plur. Fuéramos, seríamos, fuésemos hallados.

Fuérais,

seríais,

fuéseis

hallados.

Fueran,

serían,

fuesen

hallados.

First Future.

Sing. Si fuere hallado, if I should be
Si fueres ballade. [found.

Sing. Fuera, sería, fuese hallado, I
would, should, might be found. | Plur.
Fueras, serías, fueses hallado.
Fuera, sería, fuese hallado.

Si fuere hallado.

Si fuéremos hallados.
Şi fuéreis hallados.

Si fueren hallados.

The compound tenses of the passive verb are formed by the several simple tenses of haber, and the passive past participle of the verb to be conjugated; as

He sido hallado, I have been found.
Había sido hallado, I had been found.

Habré sido hallado, I shall have been found.

Si hubiere sido hallado, if I should have been found.

Se and the other personal pronouns of the first objective case are often used in Spanish with neuter or active intransitive verbs, and in such cases seem redundant in English; as, V. se burla, you jest; mucho me alegro, I rejoice much; se caerá vmd., you will fall. Those verbs designated with an asterisk (*) in the vocabulary are thus used.

Acercarse,* to approach,

to draw near.
Á las seis, at six o'clock.
A las siete, at seven
o'clock.
Alabar, to praise.
Alegrarse, to rejoice.
Armar, te arm.
Bien, well, properly.

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EXERCISE 32.-SPANISH-ENGLISH.

1. ¿Cómo se halla vmd.? 2. Los abogados se portan mal. 3. Os 4. El carpintero se halla contento. 5. Pedro se alabó. portáis mal.

6. El general se armó. 7. Se salvaron. 8. Me escondí. 9. Nos escondimos. 10. Ojalá me hallase con ella! 11. Tus amigos sa juntarán en Londres. 12. Alabáos. 13. Armémonos. 14. Armes8 vmd. 15. Me alegro mucho. 16. Se acerca el invierno. 17. V. ee burla. 18. Pedro se queja. 19. ¿De quién se quejan? 20. Siempre me levanto á las seis. 21. No se retiraría V. del pais? 22. Se alegran. 23. Alegráos. 24. Alégrense. 25. No se queje V. 26. No nos metamos en los asuntos del juez.

* Hallado means been found, as well as found, so that sido is not used in forming the passive past participle.

EXERCISE 33.-ENGLISH-SPANISH.

1. Peter behaves himself well.

2. Thou behavest thyself well. 3. They assembled (themselves) in Madrid. 4. Thou lovest thyself. 5. The woman hid herself. 6. My brothers' praise themselves1. 7. I praise myself. 8. We arm ourselves. 9. They have behaved themselves badly. 10. Oh that they would conduct themselves well! 11. Hide thyself. 12. Save yourselves. 13. Praise yourself. 14. Thou jestest. 15. The spring approaches1. 16. They complain. 17. Thou rejoicest. 18. You3 (V.) have risen. 19. Have I ever (nunca) meddled in your (de vmd.) affairs (asuntos) ? 20. I will retire.

Instead of employing the auxiliary verb ser (to be), and the participle of the verb agreeing with its nominative, the personal reflective pronoun se is often used in the third person singular and plural with the proper tense of the active verb. Thus, we may say, el libro ha sido hallado, or el libro se ha hallado (literally, the book has found itself), and both forms are to be rendered in English, the book has been found. This is a very important rule of Spanish grammar, and must be kept in mind by the student.

Abrir, to open.
Botella, bottle.

Clamor, noise, clamour.
Continuar, to continue.
Creer, to believe,
think.

to

VOCABULARY.

increase.

Doblar, to double, to Llenar, to fill.
Profecía, prophecy,
Puerta, door.
Usar, to use.
Vender, to sell.

Engañar, to deceive.
Escuela, school.

Humo, smoke.

Llamar, to call, name.

In many of the following sentences the nominative will be found placed after the verb, this being a very common order of construction in Spanish, especially in sentences in which se, with the active verb, is used in place of the passive verb.

hombre que robo al padre de Pedre. 7. Mi criado mató á su padre. 8. Perdoné á todos mis deudores. 9. Pedro me ama como á un hermano. 10. Visitaremos al presidente esta noche (to-night). 11. Recompensaré al que me honra.

EXERCISE 37.-ENGLISH-SPANISH.

1. We honour the judge. 2. This judge fears not God. 3. I forgive my debtors. 4. They called the painters. 5. The physician will heal many sick (persons). 6. They robbed the woman whom we rewarded. 7. Honour ye your parents (padres). 8. I love thee like (como) a father. 9. The ladies will reward their female servants.

KEY TO EXERCISES IN LESSONS IN SPANISH.-XII.
EXERCISE 30.

1. God loves us. 2. The painters love her. 3. The German loves truth. 4. They remain contented. 5. You seek repose. 6. Thou remainest sad. 7. Ye speak English. 8. The Frenchman does not eat bread. 9. My brothers do not drink wine. 10. You eat nothing. 11. Ye drink nothing. 12. Mary writes letters. 13. Ye write many letters. 14. You live in the city. 15. How do you like (find) this bread? 16. Mary was weeping. 17. Peter was speaking. 18. The women were weeping. 19. I was drinking wine. 20. James was drinking water. 21. I was writing a letter. 22. Thou wast living in Madrid. 23. I was seeking repose. 24. He travelled through Spain. 25. I travelled through the United States. 26. John wept. 27. I read these books. 28. We drank wine and milk. 29. I wrote two letters. 30. They wrote twelve letters. 31. They have refused him that favour. 32. John has refused me that favour. 33. Hast thou travelled through Spain? 34. Have you not eaten bread? 35. I have eaten much bread. 36. Has the judge arrived? 37. Have you found my lamps? 38. Have you travelled through the United States? 39. Till then we had not terminated our business. 40. Hadst thou not already lived in London ? 41. When I had found the treasure I wrote letters to my 1. Esta muger se llama María. 2. Se cree. 3. Este vino se vende friends. 42. When we had spoken, our sisters wept. 43. We shall á tres pesos la botella. 4. Se enagaña V. 5. ¿Qué libros se usan en travel through England. 44. I shall eat this bread. 45. They will 6. Las botellas se llenarán de água. eat apples. esa escuela ? 7. Se llenó toda 46. They will write letters. 47. My man-servant will carry la ciudad de humo. the letters to the post. 8. Aquí se habla el Frances. 9. Se abrirá la 48. They will have arrived at three o'clock. puerte. 10. Las casas se quemaron. 50. Eat this bread. 51. Fulfil 49. Weep with those who weep. 11. Aquí se venden libros.. 12. Se cumplen las profecías. 13. Este hombre se llama Pedro. your promises. 52. Eat thou with me. 53. Eat thou with Peter. 54. Let the ladies read those books. 55. Read this letter. 56. Speak Spanish. 57. Do not speak of this. 58. Thou mayest not drink wine. 59. Ye may not weep. 60. It is possible that thou mayest find a treasure. 61. It is probable that they may not fulfil their duties. 62. Oh that 64. ye may find repose! 63. If Mary should weep, John would weep. Oh that men would fulfil their duties! 65. It is possible that they may not have found a treasure. 66. Oh that I had not spoken! 67. If John had not spoken, Mary would not have wept. 68. If they shall find a treasure to-morrow, they will write to us. 69. Permit me to read that book. 70. It was necessary to speak to them. 71. They were eating and drinking. 72. Having found a treasure in the road, we carried it in the lawyer's house.

EXERCISE 34.-SPANISH-ENGLISH.

EXERCISE 35.-ENGLISH-SPANISH.

1. Here French is spoken. 2. Knock (llamád), and it shall be opened to you, 3. The clamour is doubled, 4. Are gold pens used? 5. The bottles will be filled with (de) wine. 6. The house will be filled with smoke. 7. The doors, will be opened. 8. The prophecy is fulfilled. 9. The houses are burned. 10. Here books are sold (pres.). 11. This wine is sold at two shillings a bottle. 12. The letter will be continued. 13. All the gates were opened (perf. def.).

The passive verb is sometimes formed by the auxiliary verb estar, instead of ser; as, el caballo está lastimado, the horse is injured; la casa está mal construida, the house is badly built. Verbs are conjugated interrogatively, by placing the pronoun after the verb; and negatively, by placing the adverb no before the verb; as

¿Amo yo? love I? or do I love? | El no come, he does not eat. If an objective pronoun come before the verb, the negative no is then placed immediately before such pronoun; as¿No lo habeis oido ? have ye not Yo no le vi, I saw him not. heard it?

One of the most important rules in Spanish syntax is that by which a noun in the objective case, if it be a person, or inanimate thing personified, and the direct object of a verb, is to be preceded by the preposition á. Thus "John loves his brother" would be in Spanish, Juan ama á su hermano, and not Juan ama su hermano; "Peter slew the barber" would be Pedro mató al barbero,* and not Pedro mató el barbero.

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3 Perdonamos á

stros deudores. 4. Dios ama á los

que

16.

EXERCISE 31.

1. Yo lloro. 2. Mi madre busca reposo. 3. Ella no halla reposo. 4. Hablan. 5. Hablas. 6. Lloran. 7. ¿Hablan vms. Español? 8. Hablamos Español. 9. No hallo reposo. 10. Bebes vino. 11. Bebo agua. 12. Como pan. 13. Juan lee libros. 14. Leen libros. 15. Bebemos vino. 17. Bebeis agua. 18. El No respondes nada? medico vive en Londres. 19. Mis hijas viven en los Estados Unidos. 20. Cumples tu palabra. 21. Cumplo mis deberes. 22. Llevábamos mucho dinero. 23. Las señoras buscaban reposo. 24. Yo lloraba. 25. Comíamos pan. 26. Vivían en Londres. 27. Vivíais en la ciudad. 28. Escribiamos cartas. 29. La Francesa no halló reposo. 30. Viajamos por Inglaterra. 32. 31. Hallaron un tesoro en el camino. Comis pan y manteca. 33. Comieron azucar. 34. Juan no respondió nada. 35. Vmd. vivió en Madrid. 36. He hallado mis tesoros. 37. ¿Ha llegado el correo? 38. Hemos hallado las cucharas. 39. ¿ Le habéis rehusado ese favor? 40. He cumplido mi palabra. 41. Han cumplido su palabra. 42. Has comido mucho miel? 43. Hasta entonces habíais hablado Español. 44. Ya habian comido cuando llegamos. 45. Hasta entonces habian vivido en paz. 46. Cuando hubiste comido, tu padre llego. 47. Viajaré por España. 48. Hallará un tesoro. 49. Leerás esos libros. 50. Cumpliremos nuestras palabras. 51. Habré comido á las dos. 52. El corréo habia llegado á las dos. 53. Bebed água. 54. Vivid en paz con todos los hombres. 55. Lea Maria mis cartas. 56. Cumplan los hombres sus deberes. 57. Coma V. manzanas y peras. 58. Lean vms. esa carta. 59. No léa vmd. ese libro. Respondedme. 61. Escribidles, 62. Escribanos. 63. Es posible que lean esos libros. 64. Probable es que ella no le responda. 65. Si yo hallase libros, yo los leeria. 66. Ojala! no bebiesen vino!

60.

67.

son buenos. 5. Ella ma al Americano. 6. El juez perdonó al ¡Ojala no llorase! 68. Precisa era que Maria no hablase alto. 69.

This rule applies only to rational beings or personified objects; thus we cannot say, amo á lu verdad, but amo la verdad, "I love the truth."

Es posible que no haya llegado. 70. Era estraño que no hubiesen hallado esos libros. 71. Si mañana llegare Pedro, to escribiré. 72. ¿Me permitirá V. leer esa carta? 78. Juan pretende no haber hablado. 74. Habiendo hallado un libro le lai.

LESSONS IN ASTRONOMY.-XVI.

THE SPECTROSCOPE EXAMINATION OF RED FLAMES BY MEANS

OF IT-LUNAR ECLIPSES-OCCULTATIONS-ASTRONOMICAL

INSTRUMENTS-TELESCOPES-TRANSIT INSTRUMENT.

IN the last few years our acquaintance with the physical con-
stitution of the Sun and stars has been much increased by the
invention of the spectroscope.
Sir Isaac Newton made, many
years ago, the discovery that a
ray of white light could, by
means of a prism, be decomposed

spectrum;

in fact,

of

so as to produce a
that it consisted,
rays of the seven prismatic co-
lours all blended together. On
examining the solar spectrum
thus produced, Dr. Wollaston

found that, under certain con

ditions, dark lines were to be seen crossing it in different parts. These lines were further found always to occupy the same place, and the principal ones were accurately mapped out by Fraunhofer, after whom they are named.

For some time, however, nothing arose from this discovery, nor was any satisfactory theory started to account for the lines. Several philosophers were, however, engaged in investigating the subject, among whom Professor Kirchhoff should be specially mentioned. The rays from sources of light were made to pass through prisms, and the spectra thus obtained were examined to certain whether any lines were present in them. At length it was discovered that when bodies are reduced to the state of a gas, and burn, the spectra formed but consist only of a series and that these lines vary

are not continuous,

These protuberances have now been seen at other periods; during an eclipse, however, is the most favourable time for observing them.

In history we find many notices of total eclipses, some of which created great alarm. Xenophon, in the " Anabasis," relates that a city called Larissa was besieged by the Persians, but that they were unable to take it until a cloud covered the sun, and caused it entirely to disap

pear, when the inhabitants with. drew in alarm. In one or two rupted by eclipses; and at other times they were considered to foretell the death of monarchs, or other calamities. Science

instances battles were inter

now, however, banishes all such

ideas, showing us that these

strange phenomena are but a

part of the regular mechanism

of the heavens, and teaching us the laws which govern them, and by which we can foretell the very moment at which they will

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We must now turn our attention from

eclipses of the Sun to those of the Moon. These are greatly inferior in interest to solar ones. There are, however, many points in connection with them which repay observa

The main feature of difference between solar and lunar eclipses consists in the fact that in the former the light of the Sun is not actually diminished; the dark body of the Moon merely keeps off its rays from a portion of the Earth's surface. The Moon, on the other

hand, shines only by reflected light, and an eclipse of it is caused, not by any body intervening between it and the Earth, but by the light of the Sun being cut off from it, so that the Moon for the time really ceases to shine.

T

of bright lines,

in colour and posi

tion according to the substance burnt. If,
however, the rays of light from a luminous
body pass through any gas, then in the
place of the bright lines produced by that
gas, we have a corresponding, series of dark
lines.
Now the spectroscope is an instrument for
thus examining the rays of light from various
sources. A narrow ray of light enters the in-
strument through a telescope; it then passes
through a series of prisms, by which it be-
comes opened out into a broad spectrum;
and a second telescope, fitted with a micro-
meter, is provided for examining this spec-
trum, and ascertaining the position of the
lines. Pieces of platinum wire dipped in vari-
ous salts are then placed in the flame of a
spirit-lamp, and the lines produced by each
are carefully examined, and their places noted
down; and in this way the lines charac-
teristic of most of the elements are ascer-
tained. The lines seen in the spectra of the
Sun and stars are then compared with these,
and thus many of the elements which exist
in those bodies have been discovered. The
Sun, for instance, is found to contain the
following elements :-Sodium, iron, magne-
sium, hydrogen, barium, copper, zinc, calcium,
and several others.

In the total eclipse of 1868, already referred to, the spectroscope was directed to the red protuberances with a view to ascertain something of their nature, and bands indicative of hydrogen, sodium, and magnesium were clearly traced in the spectrum.

It seems clear, then, that they belong to the solar atmosphere, and consist of gas in a state of ignition. Some of them, indeed, appear to be clouds or mountains of flame, and they are frequently in a state of violent agitation.

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By reason of this an eclipse of the Moon is visible over one-half of the surface of the globe that is, in all places where the Moon itself is seen; while a solar eclipse is, as we have seen, confined to a comparatively limited Hence, though solar eclipses are more frequent than lunar ones, in the proportion of about three to two, the solar eclipses, seen at any given place of observation, are not one-half as many as the lunar eclipses visible at the same place during the same period.

The theory of lunar eclipses will easily be understood by reference to the annexed sketch (Fig. 37); but it must, of course, be remembered that here, as in our diagram of a solar eclipse, the proportions are altogether exaggerated to render the drawing more dis

s represents the Sun, and E the Earth, the shadow of which is a long cone reaching into space a long way beyond the orbit of the Moon. This dark shadow is the umbra, and it gradually shades off into the penumbra, which is bounded by the lines BD, A F, and tapers towards the Earth, instead of away

M represents the Moon revolving around the Earth, and in its journey it sometimes passes through the dark cone, and thus becomes, for the time, almost invisible. The commencement of the eclipse is marked by a faint shade beginning to creep over the east side of the Moon's disc. The moment of this occurring is that mentioned in the tables as the first contact with the penumbra. As the Moon travels onward it enters the umbra, and the east side of its disc then becomes almost invisible. When fully immersed in the umbra the Moon may usually be feebly seen, and appears of a ruddy hue. The reason of this was for some time a mystery, but it is now known to arise from

the refractive power of the Earth's atmosphere. As the rays of the Sun are passing along in the directions A C and B C, some of them are refracted or bent inwards so as to reach the Moon. Some of them are likewise absorbed, and others are refracted more than the rest, so that it is chiefly the red rays that reach the Moon, and hence she presents a ruddy hue.

In some states of the atmosphere this is seen much more distinctly than in others. In the eclipse of the 6th of February, 1860, it was especially noticed, the light of the Moon being so strong and so red that many were unaware of the fact of its being caused by an eclipse, and were puzzled to account for the appearance. In other instances the Moon has been totally invisible during the eclipse.

The duration of a total eclipse of the Moon may be as great as 1 hour 50 minutes. This is when the Moon passes directly through the middle of the umbra.

A B

At other times it passes near the edge, and then is only obscured for a short period. When it passes through the centre of the shadow, the total duration from the first contact with the penumbra to the last may be five hours and a half.

Fig. 38 shows at one view the phenomena of both lunar and solar eclipses. The solar eclipse represented here is an annular one, as the shadow of the Moon terminates at m before it reaches the Earth. A moment's careful inspection of this diagram will show that an eclipse of the Sun can only take place at the period of the new moon, as the enlightened hemisphere is turned away from the Earth. An eclipse of the Moon, on the other hand, can only occur at full moon.

At first sight, we should suppose from this that these eclipses ought to occur at every new and full moon, and the question naturally occurs why it does not happen so. The Moon is between the Earth and Sun every new moon. Why, then, do eclipses only occur at comparatively rare intervals, instead of once every lunar month?

The simple answer to these questions is found in the fact that the orbit of the Moon is not in the same plane as that of the Earth, but is inclined to it at an angle of about 5° 9', so that during one-half of its journey the Moon is below the plane of the ecliptic, and during the other half it is above it. Now the shadow of the Earth is in the same plane as its orbit, and hence at the period of full moon the shadow may be above or below the Moon, and in either case no eclipse will occur.

The points in which these planes intersect are known as the nodes, and hence we may say that there will be an eclipse of the Moon whenever a full moon happens to occur with the Moon

to 223 synodical revolutions of the Moon, so that after this interval the Sun, Earth, and Moon are again almost in the same relative positions, and the same series of eclipses is therefore repeated. This period of 6,585 days, or 18 years and 10 days, is called a cycle of the Moon. It was known to the ancients, and called the Saros, and by means of it eclipses were roughly calculated before any great progress had been made in the science of astronomy.

It might be supposed from this statement that if we had a complete list of eclipses for this period, nothing more would be wanted, but that by repeating this series over and over again, we should have a perpetual list. This is not, however, strictly accurate, for, as the periods do not exactly agree, there is a slight change from time to time in the conditions of the eclipse, and sometimes one, after a time, passes off the list altogether. Generally speaking, however, the eclipses are thus repeated, the number usually occurring in this period being fortyone solar and twenty-nine lunar, or a total of seventy.

Another question that arises is, How many eclipses can possibly occur in one year? and we find that there must be at least two of the Sun, while there may be as many as five. The number of lunar eclipses may be as great as three, but in some years there are none at all. Reckoning both together, there cannot be more than seven eclipses, nor less than two, in one year, and in the latter case both are solar.

As the Moon and planets are constantly changing their places with respect to one another and to the rest of the heavenly bodies, it not unfrequently happens that one of the heavenly bodies is concealed by their coming between them and the Earth. This occurrence is known as an occultation. A solar eclipse is,

at or near one of the nodes. In a similar way a solar eclipse will occur when the Moon is near one of the nodes at the time of

new moon.

The position of the nodes of the Moon's orbit is continually changing at the rate of 19° 20' in a year, so that they perform a complete revolution in a trifle less than 18 years and 219 days. After an interval of 346 62 days, however, they come again into the same position with regard to the Sun, and this period is called a synodical revolution of the node. Now, it happens that nineteen of these periods are almost exactly equal

in fact, merely an occultation of the Sun by the Moon, though, on account of its importance, it is called by a special name to distinguish it.

It is only at very rare intervals that one of the planets occults another planet or a star. The most common occultations are those in which the Moon passes in front of a star or planet. As the Moon's disc is very large, many stars are thus hidden by it. Its light is, however, usually so bright that it is only the occultation of very bright stars that can be seen, the smaller ones being lost in the brilliancy of its rays. A table showing those of the larger stars which are thus hidden by the Moon is inserted in the "Nautical Almanack" for each year.

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When the Moon is only partly illuminated the star either disappears or reappears at the dark edge of her disc. From new moon to the full this dark edge travels foremost, and hence the star suddenly disappears, without any apparent cause, some little distance before it reaches the illuminated crescent. In a similar way, after the full moon, the star suddenly re-appears in the clear sky, the luminous side of the Moon's disc now being the foremost.

Many observers, in watching these occultations, have been much struck by one remarkable circumstanco often noticed in connection with them. The star does not disappear gradually by the Moon's disc creeping over it, but actually appears to travel some little distance on to the Moon's disc, and then

suddenly vanishes. Some observers have even seen the bright edge of the lunar disc outside the star before it vanished. This phenomenon has puzzled astronomers considerably, as no altogether satisfactory explanation of it has hitherto been advanced. Some have supposed it to be an optical illusion, depending partly upon the imperfect nature of the lenses employed; while others have attributed it to the different refrangibilities of the light from the star and from the Moon. By means of a telescope these occultations can easily be observed. Rare instances have been recorded in which one planet has eclipsed another, or a star, but in some of them it seems probable that they were merely in such close proximity that they appeared as one.

When planets happen to be very near together they are said to be in conjunction. It is not unusual for two planets thus to be in close proximity. Seldom, however, are several thus side by side. In September, 1186, the rare phenomenon of Mercury, Venus, Mars, Jupiter, and Saturn being all in conjunction, was observed. Ages must elapse before this can occur again. Before passing on to notice the main facts relating to the stars, it will be well just to glance at the instruments employed by the astronomer in his researches. The most important of these is the telescope; in fact, it may be said that in nearly all his instruments the most essential portion is a telescope, the mode in which it is mounted varying according to the special purpose for which it is intended.

A full description of the principle on which the telescope acts will be set before the student in a future lesson. Two objects are sought to be obtained by the use of this instrument. The one is to collect a much larger number of rays of light than can enter the unaided eye, and thus to render the illumination much greater, and discern objects too faint to be seen otherwise. The other is to cause those rays to enter the eye at a larger angle, and thus make the object appear larger than it does to the naked eye.

To accomplish these objects two different kinds of instruments are employed-the refracting and the reflecting telescope. The former consists essentially of a double-convex lens of considerable focal length, called the object-glass. The rays of light which fall on this are by it brought to a focus, and a second lens magnifies the image thus formed. Fig. 39 will illustrate this, o being the object-glass, which forms an image at A B, and E the eye-piece, which magnifies the image. The largest refracting telescope yet made has an object-glass 25 inches in diameter, and it will easily be seen how great must be the amount of light received by this when compared with the pupil of the eye, which is only one-fifth of an inch across. Earl Rosse's telescope, already referred to, is the largest reflector ever made, its speculum having a diameter of 6 feet. Telescopes of this kind consist of a long open tube, with the speculum placed at the lower end. The observer then looks in through a lens placed at the open end, or at one side.

The instrument usually employed when we want to examine the position of any celestial body is that known as a transit instrument, and represented in Fig. 40. Two pillars of solid masonry carry the bearings of the horizontal axis of the telescope. This axis points due east and west. The telescope, therefore, which is at right angles to it, describes a great circle, passing through the north and south points of the horizon, and also through the pole of the heavens. Every star will therefore be visible in the telescope at the time of its culminating or crossing the meridian. Those circumpolar stars which never set will also be visible during their lower passage of the meridian.

Great care is required in the mounting of this instrument to ensure the tube being directed due north and south. The telescope is sometimes taken out of its bearings and reversed, so as to ascertain whether it is correctly adjusted; and then, if the tube be not at right angles to the axle, it will at once be detected. The polar star also affords another means of testing the instrument, for, as it is not situated directly at the pole, it describes a small circle round it, and the visual ray of the telescope should divide this circle into two equal portions. If, then, we notice three successive upper and lower transits, and the intervals between them are exactly equal, we may conclude that the instrument is correctly adjusted. The weights shown in the figure relieve the bearings of a portion of the strain.

READINGS IN LATIN.-XII.
TERENCE.

P. TERENTIUS AFER, the greatest master of Roman comedy, flourished some years after Plautus, whose comedies were noticed in the previous Readings, and whom he excelled in greater purity of diction and finish of style, though he cannot be credited with greater originality than his predecessor, being equally dependent with him upon Greek sources for the form of his plays, the outlines of their plots, and the names and individuality of his characters. He is said to have lived at the end of the second Punic war, and to have been a Cartha ginian slave, which latter statement is borne out by his name, Afer (the African). He is only known to have written six plays, all of which have come down to us, and which bear the fol lowing titles-"Andria," " "Hecyra," "Eunuchus," "Heautontimoreumenos," 'Adelphi,"" Phormio." It is needless to give in detail the plots of any of these; they none of them give a very high idea of the morality of the age, and principally turn on lovers' intrigues, the father's wrath-a serious thing in a country where the father was allowed absolute control over his children-and the shifty machinations of ingenious slaves, whose cunning, if not always successful, is generally the most amusing element in the piece.

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A few words are necessary to explain the following extract from the "Andria." Pamphilus, son of Simo, has fallen in love with Glycerium, a native of the isle of Andros-hence the title of the play. His father, hearing of it, and thinking the marriage not likely to be a very creditable connection, orders him to marry the daughter of his old friend Chremes. Davus, the slave of Simo, who has a plot in his head for setting matters right, induces Pamphilus to profess submission, and it accordingly becomes known that Pamphilus is to marry the daughter of Chremes (Philumena), with whom Charinus, a friend of Pamphilus, is already in love; and Byrrhia, the slave of Charinus, has just informed him of the report.

ANDRIA, ACT II., Sc. 1, 1. 2-28.
CHARINUS. BYRRHIA, PAMPHILUS.

CH. Va misero mihi.

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Tu si hic sis, aliter censeas. Br. Age, age, ut lubet. CH. Set Pamphilum 10 Video. Omnia experiri certum 'st prius quam pereo. BY. Quid hic agit ?

CH. Ipsum hunc orabo: huic supplicabo: amorem huic
narrabo meum:

Credo impetrabo, ut aliquot saltem nuptiis prodat dies
Interea fiet aliquid, spero. Br. Id aliquid nihil est. CH.
Byrrhia,
Quid tibi videtur? adeon' ad eum? Br. Quid ni? nihil
ut impetres,

Ut te arbitretur sibi paratum mochum, si illam duxerit ?
CH. Abin' hinc in malam rem cum suspicione istac, scelus ?
PA. Charinum video. Salve. CH. O salve. Pamphile,
Ad te advenio, spem, salutem, consilium, auxilium expetens.
PA. Neque pol consili locum habeo, neque ad auxilium
copiam.

Set istuc quidnam 'st? CH. Hodie uxorem ducis? PA.
Aiunt. CH. Pamphile.
Si id facis, hodie postremum me vides. PA. Quid ita? CH. Ei
mihi,
Vereor dicere: huic dic quæso Byrrhia. By. Ego dicam.
PA. Quid est ?

Br. Sponsam hic tuam amat. PA. Ne iste haut mecum
sentit. Ehodum dic mihi :

Numquidnam amplius tibi cum illa fuit Charine? CH. Ah,
Pamphile,

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