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on

Aor. pass.

Middle,

Remarks, . Present, κωλύ-ομαι, impf. ε-κωλύ-ομην, -ύ.

“Οτε οι βαρβαροι, etc. Assistance may sometimes be ob. Future, κωλύ-σομαι, aor. ε-κωλύσαμην, -ύ.

tained towards understanding and construing a sentence by Perfect, κε-κωλύμαι, perf. fut. κε-κωλύ-σομαι, plpf. ε-κε- | simplifying the arrangement, that is, by bringing the arrangeκωλύ-μην, -ύ.

ment nearer to the English. I advise the student to make Passire.

the experiment. When he has got his new arrangement, he Aorist, ε-κωλύ θην, fut. κωλύ-θησομαι, -ύ.

may put the corresponding English, word for word, under the

Greek; and having studied the whole thus prepared, finally Contrary to the rule, several pure verbs retain the short put the English terms into good or idiomatic English; e. g. characteristic vowel either in all the tenses or in some of

oi

ότε them. These verbs take a o in the Perfect and Pluperfect The barbarians tied in running, when they became aware of

βαρβαροι εφευγον δρομο,

φσθανοντο middle or passive, as well as in the first Aorist and Future passive, also in their verbal adjectives: this fact is indicated των ασπιδων κεκρoυσμενων προς τα δορατα υπο των thus, pass, with o; accordingly,

the shields having been dashed the spears by the

| Ελληνων. χρίω, I sting, f. χρίσω, 8, εχρίσα, inf. χρίσαι ; pass. with σ;

Greeks. but, χρίω, I ruo, anoint, f. χρίσω, a. εχρίσα, inf. χρίσαι, a. m.

That is, the barbarians took to flight when they heard the εχρίσαμην; p. m. or p. κεχρίσμαι, inf. κεχρίσθαι; a. 1. | Greeks dash their shields against their spears, εχρίσθην, ν. 4. χριστος.

Mark the quantities, short or long , of the vowels in your ανύω, I complete, f. ανύσω, a. ηνύσα, inf. ανύσαι, pass. with σ. Greek renderings of the English-Greek Exercise, agreeably to αρυω, I draw, f. αρύσω, a. ηρύσα, ηρύσαμην, pass. with σ.

the statements just now made. μυω, I close (e. g. the eyes), f. μυσω, a. εμίσα, p. μεμύκα, Ιαηη

Exercises.-GREEK-ENGLISII. closed, I am silent. πτυω, I spit, f. πτύσω, a. επτυσα, pass. with σ.

Οι στρατιωται προς τους πολεμιoυς πορεύεσθαι εκελευσβησαν. The following dissyllable verbs in θω lengthen the cha- Σπαρτη ποτε υπο σεισμου δεινως εσεισθη. Η των Περσων racteristic vowel in the Future active and middle, the third δυναμις υπο των Ελληνων τεθραυσται. Οι πολεμιοι εις την Future, and the Aorist active and middle; and δυω also in ακραν κατεκλεισθησαν. Οτε οι βαρβαροι των ασπιδων προς the Perfect and Pauperfect active; but in the Perfect and

τα δορατα υπο των Ελληνων κεκρoυσμενων φσθανοντο, δρομή
Pluperfect active (except ouw) and middle (or passive), and
in the Aorist and Future passive, resume the short Towel : εφευγον. Ο πολεμος κατεπαυσθη. Ελπιζομεν παντα ευ ανύσειν.
thus,

Ειθε παντα καλως ανύσαιμι. Η συνθηκη υπο των βαρβαρων
Fut.
Aor. . Perf.

λελυται. ovw, I enter, δυσω εδυσα δεδυκα, δεδύμαι εδύθην

ENGLISH-GREEK. Hvw, I sacrifice, θυσω εθυσα τεθύκα, τεθομαι ετύθην λυω, Ιιοο8e, λύσω ελυσα λελύκα, λελύμαι ελύθην

The soldiers have been commanded to go against the enemy.

Our city has been broken by an earthquake. That city The pure verbs which retain the short characteristic vowel will be broken by an earthquake. The city is shaken (Prein the tenses, interpose o before the tense-endinga ony, jar, sent) by an earthquake. The power of the Persians was etc. in the first Aorist and first Future passive, and in the broken by the Greeks. The enemy (plural) has been shut Perfect and Pluperfect middle or passive, as well as in the up in the citadel. The shields were struck against the spears verbal adjective. This peculiarity is observed by several by the enemy. The war has been made to cease (terminated). other verbs, which either have a long vowel in the root, or The war will have been terminated, May we complete all things lengthen in the tenses a short vowel in the root; as, akouw, I well! (opt. Aor.) To command (Aor.) is easier than to como hear, evavw, I set on fire, Opavw, I break in pieces, «povw, I dash, plete (Aor.). The treaty will be broken by the enemy; thou ψανω, 1 touch, σειω, I shαλα, κελευω, 1 command, λευω, I stone, hast been commanded; he had been commanded; I have κλειω, I shut, πταιω, I knock against, χριω, I snear.

enclosed; they have enclosed; thou hast sacrificed; I shall Ilavw I cause to cease, has the Pertect middle or passive firish; to sting; to anoint; the bull has been sacrificed; they πεπαυμαι, but Aorist passive επαυσθην.

will have been commanded.
Kelevw, I order, command-Perfect Middle or Passive.
Indicative.
Imperative. ,

ETYMOLOGICAL VOCABULARY.
S. 1. κε-κελευ-σ-μαι

The word στρατιωτης is connected with a numerous list of
2. κε-κελευ-σαι

κε-κελεύ-συ

terms, and may be made a key to the treasure. The root is 3. κε-κελευ-σ-ται

κε-κελευ-σθω

στρατ, which is found in its simplest form in the noun στρατια, D. 1, κε-κελευ σ-μεθον

an army, and the root otpat (compare the Latin strat in stra. 2. κε-κελευ-σθον

κε-κελευ-σθον

tum from sterno) is connected in origin and import with 3. κε- κελευσθον

κε κελευ- σθων

στρωνυμι, I spread out, I corer, as a camp occupies a field, 80 Ρ. 1, κε-κελεύ-σ-μεθα

that otparoç is properly a camp or an organised army, and 2. κε-κελευ-σθε

κε-κελευ-σθε

στρατια an embattled troop. . 3. κε κελευ-σ-μενοι εισι κε -κελεν-σθωσαν

στρατια, ας, ή, an army. Pluperfect.

στρατευμα, ατος, τo, an army.

στρατιαρχης, ου, o, a leader of | στρατευσειω, I desire an army,
Sing.
Dual.

Plural.

an army (αρχος, a leader). an expedition. 1. ε-κε-κελευ-σ-μην ε-κε-κελευ-σ-μεθον

ε-κε-κελευ σ-μεθα
στρατιος, 2 and 3. relating to

στρατευσις, εως, ή, army-ser. 2. ε-κε-κελευ-σο ε-κεκελευ-σ στον ε-κε-κελευ- σθε

vice. 3. ε-κε-κελευ-σ-το ε-κε-κελευ-σ-στην ε-κε-κελευ-σ-μενοι στρατιωτης, ου, o, a soldier.

στρατευω, more common στρα

ησαν Aor. pass. εκελευ-σ-θην.

τευομαι, I serve in the army. Fut. pass. κελευ-σ-θησομαι.

three terminations), relating orparnyew layw, I lead), I lead

to a soldier. VOCABULARY.

στρατιωτις, ιδος, ή, a ship for στρατηγια, ας, ή, the ofice of Καταπαυω, I terminate, bring, Δρομος, ου, o, a running.

transporting suldiers, atrans

a general,

port ship. to an end. Ασπις, ίδος, ή, a shield.

στρατηγικος, 3. relating to και Αισθανομαι, (with gen. Or ace.) Δυναμις, εως, ή, power.

στρατοομαι, I encamp, I am

general's office. I am aware of, I perceive.

Δεινως, greatly, exceedingly, στρατοπεδον, ου, τo, a camp, Σεισμος, ου, o, an earthquake, fearfully. .

an army in camp, an army.

an army.

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στρατηγος, ου, o, a general.

| always receive its due share of seasonable attention, many LESSONS IN READING AND ELOCUTION.

errors in pronunciation are apt to occur in the exercise of No. VIII.

reading, as performed by even the advanced classes in schools.

To avoid such errors, it will be found useful to discuss, closely ANALYSIS OF THE VOICE.

and minutely, the correct pronunciation of every word which III.-DISTINCT ARTICULATION.

in any lesson is liable to be mispronounced. The standard "Correct articulation is the most important exercise of the of reference ought to be Walker's Dictionary, or the same voice and of the organs of speech. A reader or speaker, work improved by Smart. possessed of only a moderate voice, if he articulate correctly, will be better understood, and heard with greater pleasure,

V.-TRUE TIME. than one who vociferates. The voice of the latter may, indeed, extend to a considerable distance; but the sound is dissipated By true time in elocution is meant an utterance well-proin confusion : of the former voice not the smallest vibration is portioned in sound and pause, and neither too fast nor too wasted-every sound is perceived at the utmost distance to slow. We should never read so fast as to render our reading which it reaches; and hence it even penetrates farther than indistinct, nor so blow as to impair the vivacity, or prevent the one which is loud, but badly articulated.

full effect, of what is read. In just articulation, the words are not hurried over, nor “Everything tender or solemn, plaintive or grave, should precipitated syllable over syllable; nor, as it were, melted be read with great moderation. Everything humorous or together into a mass of confusion; they are neither abridged sprightly, everything witty or amusing, should be read in a nor prolonged; nor swallowed, nor forced, and, if I may so brisk and lively manner. Narration should be generally express myself, shot from the mouth; they are not trailed nor equible and flowing; vehemence, firm and accelerated; anger drawled, nor let slip out carelessly, so as to drop unfinished. and joy rapid; whereas dignity, authority, sublimity, reveThey are delivered out from the lips, as beautiful coins newly rence, and awe, should, along with deeper tone, assume a issued from the mint, deeply and accurately impressed, perfectly slower movement. The movement should, in every instance, finished, neatly struck by the proper organs, distinct, sharp, be adapted to the sense, and free froin all hurry on the one in due succession, and of due weight."*

hand, or drawling on the other,” The pausing, too, should be This department of correct reading belongs, properly, to carefully, proportioned to the movement or rate of the voice; the stage of elementary lessons. But negligence in general and no change of movement from slow to fast, or the reverse, habit, and remissness in early practice, are extensively the should take place in any clause, unless a change of emotion is causes of an imperfect articulation,

implied in the language of the piece. A page or a paragraph of every reading lesson should, previous to the regular exercise, be read backward, for the

Exercises on Tiine. purpose of arresting the attention, and securing every sound in every word.

The 'slowest' and the quickest rates of utterance have The design of the present Lesson does not admit of detail | been exemplified under the head of versatility' of voice, and in the department of elocution now under consideration. The need not be repeated here. They occur in the extremes of importance, however, of a perfectly distinct enunciation can grave and gay emotion. never be impressed too deeply on the mind of the student. An There are three important applications of time' in conexact articulation is more conducive than any degree of loud. nexion with 'rate,' or movement,' which frequently occur ness, to facility of hearing and understanding. Young readers in the common forms of reading and speaking. These are the should be accustomed to pronounce every word, every syllable, slow, the moderate, and the lively.' The first of these, and every letter, with accuracy, although without laboured the 'slow,' is exhibited in the tones of awe, reverence, and solen. effort. The faulis of skipping, slighting, mumbling, swallow- nity, when these emotions are not so deep as to require the ing, or drawling the sounds of vowels or of consonants, are slowest movement of all: the second, the moderate,' belongs not only offensive to the ear, but subversive of meaning, as

to grave and serious expression, when not so deep as to require may be perceived in the practice of several of the following the 'slow'movement; it belongs, also, to all unempassioned examples.

communication, addressed to the understanding more than to

the feelings : and it is exemplified in the utterance of moderate, 1. " That lasts till night : that last still night."

subdued, and chastened emotion: the third rate, the “lively,' is 2. “He can debate on either side of the question : he can perhaps sufficiently indicated by its designation, as characterdebate on neither side of the question."

ising all animated, cheerful, and gay expression. 3. "The steadfast stranger in the forests strayed.". 4. “Who ever imagined such an ocean to exist?- Who ever be exemplified perfectly and at once.

All the exercises on time,' should be repeated till they can

Previous to practising imagined such a notion to exist ?"

the following exercises, the student will be aided in forming 6. "His cry moved me : his crime moved me."

distinct and well-defined ideas of time,' by turning back to 6. "He could pay nobody; he could pain nobody."

the example under .versatility,' marked as very slow,' and 7. "Up the kigh hill he heaves a huge round stone." repeating it, with close attention to its extreme slowness. He 8. " Tho' oft the ear the open vowels tire."

will observe that, in the repeating of this example, the effect 9. "Heaven's first star alike ye see.”

of 'time,' or proportion of movement, is to cause a remarkable

lengthening out of the sound of every accented vowel; an IV.-CORRECT PRONUNCIATION.

extreme slowness in the succession of the sounds of all letters, That pronunciation is correct which is sanctioned by good syllables and words: and along with all this, an unusual usage, or custom. Good usage implies the habit of persons length in all the pauses. It is this adjustment of single and of good education, as regulated by the decisions of learning successive sounds and their intermissions, which properly and taste, exemplified in standard dictionaries, –a style which constitutes the office of time' in elocution : although the is equally free from the errors of uneducated or negligent term is often indefinitely used rather as synonymous with the custom, and the caprices of pedantry, -which falls in with word 'movement,' as applied in music. the current of cultivated mind, and does not deviate into The slow' movement differs from the slowest,' in not peculiarities, on the mere authority of individuals. Good possessing the same extreme prolongation of sound in single iaste in pronunciation, while it allows perfect freedom of choice, sowels, or the same length of pause. The slow succession of as to the mode of pronouncing words liable to variation in sounds is, however, a common characteristic in both. sound or accent, requires a compliance with every fixed point

Example of Slow' Movement. The subject of pronunciation, like the preceding one,

“Thou, who did'st put to fight articulation,-belongs properly to the department of elemen- Primeval silence, when the morning stars tary instruction. But as this branch of elocution does not Exulting shouted o’er the rising ball ;

0 Thou, whose word froin solid darkness struck Austin's “ Chironomia," pp. 37, 38.

That spark, the sun, strike wisdom from my soul I"

of sanctioned usage.

.

Moderate.'

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1

Here it will be observed that the order of the bodies in this
ON PHYSICS, OR NATURAL PHILOSOPHY. table is the reverse of that in the table of reflecting powers.

MM. De la Provostaye and Desains, who have recently made
No. XXXII.

researches relating to the emissive powers of bodies, have
(Continued from page 68.)

obtained numbers very considerably different from the pre

ceding. CALORIC.

Identity of Absorbing and Emissive Powers.-The absorbing

powers of bodies cannot be deduced from their reflecting ABSORPTION OF CALORIC,

powers, because, as we have seen, they are not exactly comAbsorbing Power.—The absorbing power of bodies is that I plementary to each other. But the absorbing powers would property by which a greater or less qnantity of radiant heat is body, to the emissive powers. MM. Dulong and Puit have

be determined if we could prove that they are equal, in each always in the inverse ratio of their reflecting power that is, inferred this from the following experiment. "In a large glass the more that a body reflects radiant caloric the less it absorbs vessel, which was kept at the freezing point by immersion in it, and conversely. But the absorbing and reflecting powers thermometer heated at first to a certain temperature-say, 16

ice, and which was blackened in the interior, they fixed a are not complementary to each other ; that is, the sum of the quantities of the heat reflected and 'of the heat absorbed do Centigrade ; then, having made a vacuum in the vessel by

means of a tube in it, which formed a communication between not represent the whole of the radiant heat which falls upon it and an air-pump, they allowed the thermometer to cool by a body. It is always less than this; which shows that the degrees, and they marked the time which it took to fall from incident heat is really divided into three parts: lst, that 10° to 50. Repeating the experiment in an inverted order, which is absorbed; 2nd, that which is regularly, reflected, that is, keeping the sides of the glass vessel at 16. Centigrade, according to the laws already demonstrated; 3rd, that which and cooling the thermometer to the freezing point, they obis irregularly reflected—that is, in all directions, and which is served the time which the thermometer took to rise from 5° !) called diffused heat. In oruer to determine the absorbing power of bodies, Leslie the same as that which it took to fall from 10° to 5o Centi

10° Centigrade ; and they found that this time was exactly employed the apparatus already described in the investigation of their reflecting power (see ng. 169, p. 68): but he removed grade; therefore, they concluded from this, that in the same the plate a and placed the bulb of the thermoscope in the real and that of the surrounding medium, the emissive power is

body, and for the same difference between its temperature focus of the mirror. This bulb being, successively covered equal to the absorbing power, since the quantity of heat with lamp-black, varnish, gold-leaf, silver-leaf, copper-leaf, emitted and absorbed in the same time is equal. etc., the thermoscope under the influence of the source of heat », indicated a temperature which was higher in propor being equal, every cause which modifies the one necessarily

Modifying Causes. — The emissive and absorbing powers tion as the substance which covered the bulb in the focus modities the other in a similar manner, absorbed a greater quantity of caloric. In this manner, Leslie proved that the absorbing power of a body increased as its power, since it acts inversely to the other two, erery cause

which increases them diminishes it, and conversely. We reflecting power diminished." Yet, in these experiments, the have seen that these different powers vary in different sube ratio of the absorbing powers of different bodies cannot be stances ; that the metals have ihe greatest reflecting power, inferred from that of the temperatures indicated by the ther- and lamp-black the least. But that in the same body these this law being only true in the case of bodies whose substance powers are also modified by the degree of polish, by the dendoes not change ; whilst that which covers the bulb in the of the incident rays, and lastly by the nature of the source of

sity, by the thickness of the radiant substance, by the obliquity focus varies at every observation. The ratios of the absorbing

heat. powers are, however, deducible from that of the emissive powers.

It was formerly supposed that the reflecting power gene. Emissive Power - The emissive power of a body is the pro- rally increased with the degree of polish in the surface, and perty by which it emits, at the same temperature and from that the other powers, on the contrary, diminished.' But the same amount of surface, a greater or less quantity of heat. M. Melloni has proved, that if a polished metallic plate

be The same apparatus, represented in fig. 168, p. 63, was stili roughened by scratching lines across its surface, sometimes its employed by Leslie in determining the emissive power of reflecting power is diminished and sometimes it is increased, a bodies. For this purpose, however, the bulb of the

thermo- phenomenon which he explains by the greater or less density scope was also placed in the focus of the mirror, and the faces of the reflecting metallic plate. "If the plate has first been of the cube as were formed of different metals, or covered with hardened, its homogeneity has been destroyed by the process diferent substances, as lamp-black, paper, water, etc. The of hardening ; its particles are closer together at the surface cabe being filled with boiling water, and all the other condi- !han in the interior of the maes, and the reflecting power is tions remaining the same, Leslie successively turned each face the interior, which is less dense, is exposed to view, and the

But when lines are scratched across its surface, of the cube towards the reflector, and marked the temperatures indicated by the thermoscopć. Now, in the experiment

reflecting power is diminished. where the face of the cube was covered with lamp-black, the has not been hardened, and is homogeneous throughout, the temperature in the focus of the mirror rose higher than in all reflecting power is increased by the process of drawing lines The other experiments ; and the

metallic faces produced the across its surface with a sharp instrument; and this arises lowest temperatures. By applying the law of Newtors, and from an increase of density at the surface occasioned by the representing the heat emiited by lamp. black at 100, "Leslie pressure of the tool employed in drawing the lines. derived from his experiments the following table of the emis

The thickness of the radiant substances may also modify sive powers of bodies :

their emissive power, as proved by the experiments of Leslie,

Rumford, and Melloni. The latter philosopher found that by
Bodies.

Emissive Powers. varnishing the faces of a metallic cube filled with water at a
Lamp-black

constant temperature, the emissive power increased with the
100

number of the coats of varnish, until it reached sixteen coats, Paper

98

and that beyond this number this power remained the same, Sealing.wax

95

whatever was the number of additional coats. He found by Crown Giass

90

calculation that the thickness of the sixteen coats was about China Ink

the one 6350 th part of an inch. As to the metals, gold-leaf Isinglass

80

varying in thickness from the two hundred thousandth part of Dull Lead

an inch to the fifty thousandth part of an inch, having been Mercury

20

successively applied to the faces of the cube, the diminution Polished Lead

19

of the radiant caloric was the same. Whence it appears that Polished Iron

in the metals the thickness of the coat has no influence on its
Tin, Gold, Silver, Copper, etc.

12
radiating power.

VOL. V.

1

100

Water

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M. Molloní hns also found that the absorbing power varies 1st. The nature of the substance of which the screens (the
with the naturo of the source of heat. For example, for the diathermous bodies) are formed, through which the caloric
Bame quantity of incident heat, the carbonate of lead absorbs passes.
nearly twice as much of it, when it is emitted from a cube full 2nd. The degree of polish given to these screens.
of boiling water, as when it is emitied from a lamp. Lainp- 3rd. The thickness of the screens.
blnck is the only pubstance which always absorbs the same 4th. The number of the screens through which the calorie
quantity of heat whatever may be the nature of its source. passes.

The absorbing power raries with the inclination of the 5th. The nature of the screens already passed.
Incident raya. It is at its maximum at the normal incidence, 6th. The nature of the source of heat.
and it diminishes in proportion as the incident rays depart
from the normal position. This is one of the reasons why the on different liquids placed successively in a glass trough,

Effect of the Nature of the Screens.-By making experiments
sun heats more in summer than in winter; for in summer the whose opposite faces were parallel and distant from each other
solar rays fall less obliquely on the earth's surface.
Appinutions of Rudiant ilial.- The properties of the different cions given by the apparatus, when the liquids were placed in

about four-clevenths of an inch, and by comparing the indicapowers of radiant heut, fetecting, absorbing, and emissive, the trough, with the effect observed when the caloric acted invo numerong applications in domestic economy and the arts. directly, N. Melloni found that from 100 incident rays pro. For instance, in selecting raiment for winter or for summer, ceeding from an Argand lamp as the source of heat, the preference should be given to that which is white; because following were allowed to pass through the different substances ile emissive power of white garments is less than that of black; mentioned in the table :-* consequently they are more opposed, during winter, to the loss of the heat of the human body. Again, in summer,

Substances.

Rays Passed. in consequence of their renk absorbing power, they absorb less

Bisulphuret of Carbon

63 of the heat of the atmosphere than those that are black; and

Olive Oil

30 it is for this reason that ihey appear to be more cool. For the

Ether

24 same reasons, Nature has given to the animals which inhabit

Sulphuric Acid

17 the polar regions a covering of white hair, especially during

Alcohol

15 the winter.

Sugar or Alum Water

12 In precis employed for heating liquids, such as coffee-pots,

Distilled Water

11 it is more advantageous for this purpose that their surface seuld be black and unpolishev, tecause then their absorbing By making experiments in the same manner on different power is the greatest, l'he shining appearance which we are solid substances cut into laminæ, or thin plates, whose thick. soonstemed to give them is obtained at the expense of fuel. ness was about one-tenth of an inch, M. Melloni found the ll, on the contrary, we wish to preserre a liquid warm as long results giren in the following table, 100 incident rays of heat as possible, tre must put it in a metal ressel which is polished being allowed to fall on each :and clear, because the emissive power is then lcast, and the being more slow.

Substances.

Rass Passed.
In the ape, the mountaincers accelerate the melting of the

Rock-salt

92 snow by covering it with earth, which increases the absorbing

Calcareous Spur

62 per. In our house, the exterior coatings of stores and of

Plate Glass

62 beating apparatus should be black, in order to gire free emis.

Smoky Topaz

57 82 B the carte; en the contrary, the initsior of our china.

Carbonate of Lead

52 rers should be lined with porcelain plates or Dutch ware,

Alabaster

20 white and fli sei, in order to increase the titlecting power of

Alum

12
the tiny, and heat the roms more effectively.

Sulphate of Copper
TRAXSUISSION OF RADIANT CALORIC,

From the preceding tabulated results, me conclude that

some substances, more or less imrerrious to 'ight, as the topaz
wilPaw-There are some bodies which allow smoked, is tolera", p. Trious to hear; while some substances
radiant heat to y*&* through then, just as dias de us bodies little perrious to heai, as alabaster and alum, are very dispha-
admit the passage of light through them; other boules rous. These experiments would lead also to the conclusion,
have not this properip, or possess at euis in a slight degree that there is no point of relatio-ship between the diathermous

Alcune tiss giren to the former the name of a 21 hermes and the diapharrus pitrers of bodies.
havia ani to the latter the name of atherous bodies. The Evet of 'r 'ish. The dia hern: power of a sereen it.
pass an ide warhermous tokies: the metals are entire is crises with its degree of polish. Thus M. Melloni found that
sidempus Notwithstanding the analigy which exists be the in icatiins of his aparatus varied from 129 to 5° Centi

.
{wwa mitant outs and light, it shound be observed in crade, by interposing screens of gins of the same structure
minttu ta var subsea aent irquines, that transparent bodies ad thickness, but digerent in the nature of the polish – that
aty nie mimari the waist authernous, ard that opaque bodies is, in being wire or less ground,
arv ********** athcmus
Mi Timista a Girona, 2-1 N. Dear:rcle, in France, in through a dar erm.cus screen decreases as the thickness in

OF T3.–The quanti'y of best which passes
isil ard ise d speed more of the phenomera wiicb crases, but the absarption is to proportional to the thick.
...stbyra aus Avits rat; basi wa ni ti i8s2 lat 2. sessIn general, the assort:ion takes jiace in the first layers
Varmes of an interans them meira apparatus to of costs of the thickness Borord a certain tbickness the
A barna er det ute cat a part of the dias quantir of beat transacted tea'is to rezan a constant quan-
tez aus pup? *** srd dui. In has esperiments

, r, era when the thickness continues to increase. M. Mel. td styrer Sie seuns of hatte si, ako ni has prored this time or experimetus on plaies of crowa wiwit ai is here la giuss, Wahandisior, and fiess wise theres es mere 'as the numbers 1, 2, 3, and 4; mida smir currenti itd. an Agend jaan, that asiasa he found iba out of 1,07 rars of inci lent hest

, these
en del of curreni small

such are the places imited the furgrats to pass terectirely; Filos
Sivi camp. a *""'
pan wan af a matras

tas, ar3399; ssd Berences of these numbers
ide

dag** , asari YN O female bourserah **bo nini wa waist kept at that there is

more Sex-The increase of the number ******** pe Saudenei and heared to file se des ersteh wich case rasens, produces an effect die drie dae of a sentiap lanseresus to the animate of the illness; that is, the abromaner te au beacus p**ad the applicationis rapin the fuzber of the screens; ve M. de las preved the sacos sbeut tot, un disilturis, the guy of hear absorbed decreases var med sebou Pam-causes which, pates of the same kind se pissed together, they stop more

ma screen to the stoe. Marroter, if several i de lucru 3x*22 i ste sex za am55,- than a sngie nasie van sess equal to the sum of

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