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alone. Dividing the weight of the wood by this, we ascertain weighted so as to keep the instrument vertical, and the tube, its specific gravity.

by a wire stem, carrying another tray, CD. A small mark is Grains.

made on the stem at o. For example, a large cork was found to weigh in air 743

The instrument is first carefully weighed in air; this weight The brass sinker weighed in air

8531 being constant, should be marked on it. The weight which

must be placed on c d to sink the instrument to the mark o should Weight of the compound body

92704

also be carefully noted. To ascertain the In water it weighed

specific gravity of a solid by it, the subTherefore a body of water equal to it in balk weighed

stance is first laid on the upper tray, and

48104 Now the sinker weighed in air

853.1

weights added till the instrument sinks
» in water
7570

to the mark 0. The difference between

[graphic]

this and the former weight will give that Weight of water equal to it in bulk

96.1 of the solid in air. Now remove the solid

from CD, and place it in the lower pan, Therefore the weight of water equal in bulk to the

EF. Some water will be displaced, and cork is.

385-3

the instrument will rise. We accordingly
74-3
Its specific gravity, then, is

0 192.

add more weights till it again rests with 385-3

o at the surface. The weights added are The piece of cork in this case was porous and contained air, equal to that of the water displaced, and and therefore its gravity appears much less than that of cork if we divide the weight of the substance really is, it being usually set down in the table as 240. Aby this we ascertain its specific gravity. rough estimate of the specific gravity of such a sub

Thus 450 grains had to be placed on CD 930

stance may be formed by observing to how great a to sink the instrument to the mark; when,
depth it sinks in water. If three-fourths of it is im- however, a piece of granite was laid on
mersed, its specific gravity is 0.75.

the scale, 237 grains only were required. In the manufactures it is frequently required to The granite, therefore, weighed 213 grains. Fig. 15. know the strength of some solution, and this may be On being transferred to the lower tray, Fig. 17.

found by ascertaining its specific gravity. The strength 79 grains had to be added to cd. The of spirit is thus taken by the excise; milk is also sometimes specific gravity of the granite was therefore P3, or 2.696. tested this way to find whether or not it is adulterated. In

When we want to use the instrument to find the specific such cases no very great degree of accuracy is required; the gravity of a liquid, we merely observe what weight is required process, however, must be simple, so that it may be carried out to sink it in the liquid to the mark on the stem. To this we by a man without much special knowledge. Several piecos of add the weight of the instrument, and thus find the weight of apparatus have accordingly been devised, which are known by liquid equal to it in bulk. But we know the weight of an equal different names according to the special purposes for which bulk of water, for we found before the weight required to sink they are intended. Hollow glass beads are prepared, and the instrument to the same depth in water; we have, therefore, weighted so as to have different specific gravities, which are to divide the weight of the liquid by that of the equal bulk of plainly marked upon them. If we take a series of these, and water, and the quotient is its specific gravity. drop them successively into the liquid to be examined, we For instance, an hydrometer weighed 600 grains, and, as shall find that some will sink, but we shall come at last to above, 450 grains had to be added to sink it in water to the one that just floats on the surface, and this shows the density. mark. When dipped into the liquid to be tested, 310 grains For instance, if that marked .930 sinks, and .920 floats, we only were required : what was its specific gravity ? know that the specific gravity of the liquid is between these The weight of water equal in bulk to the hydrometer is 600+ two.

450 or 1050 grains, that of an equal bulk of the liquid, 600+310, More usually, however, an instrument, called an hydrometer, or 910. The specific gravity, therefore, is fogo, or 0-866.

is employed. It consists of a hollow Now, though it is found that water answers well as a standard bulb of glass, A, carrying above it a for the comparison of the specific gravities of solids and liquids, thin tube, with a scale marked on it, gases are so very much lighter than it, that it is much more or on a paper enclosed in it. A smaller convenient to take some other substance as a standard to combulb is also blown beneath A, into pare them with. A cubic foot of air at a temperature of 60°,

which mercury or shot are put, so as and when the barometer stands at 30, weighs about 536 grains, D to adjust the weight, and at the same or nearly 1} ounces, while a cubic foot of water weighs 1,000

time cause the instrument to float in ounces; the specific gravity of air, taking water as the standard. a vertical position. The liquid to be would, therefore, be 0.00122, and that of hydrogen gas less examined is poured into a tall glass than ti of this. Such numbers would be very difficult to rejar, D, and the hydrometer immersed; member, and awkward to work with; air, therefore, is fixed on the specific gravity may then be read as the standard for the specific gravity of all gases and vapours. off from the stem.

The temperature and pressure, however, very greatly alter the Fig. 16.

It is manifest that the denser the bulk of any gas. It is, therefore, necessary to fix on some given

liquid, the higher the instrument will temperature for the standard. Now, as in the case of water, float in it, the weight of the liquid displaced being always equal 60° is found to be a very convenient temperature, the pressure to that of the hydrometer. If we want great delicacy, the indicated by the barometer standing at 30 is also fixed on. bulb must be made large and the tube small; sometimes the It is not, however, always convenient to bring the gas to this latter is removed and replaced by a graduated wire, and thus temperature; we therefore ascertain the bulk at any temperature, great accuracy is obtained; but the greater the accuracy, the and from that calculate what its bulk would be at 600. It is

These instruments are usually supplied in found that a gas expands about do of its volume at 0° Fahrenests. Sometimes two are used, one for liquids lighter than water, heit for each degree it rises in temperature ; that is, 460 cubic the other for those heavier; but it is better to have more, each inches at 0° will measure 470 at 10%, 520° at 60°, and so on. one having a range of about .200; say, for instance, one from Now the weight of 100 cubic inches of air at 600 is 31.0117 .600 to 800, another from 800 to 1.000, and so on. This in. grains, or that of a cubic foot, 536 grains. If, then, we know strument, when manufactured for testing milk, is called a lac- the weight of any bulk of gas, and the temperature at which it tometer—when for ascertaining the strength of spirit, an is weighed, we can tell its specific gravity. Thus 80 cnbic alcoholmeter, and by other names when made for other purposes. inches of a gas at a temperature of 40° weigh 35 grains : what The only difference, however, is in the graduation and the is its specific gravity ? We first find what volume the 80 cubic range.

inches will occupy at 60o. By the rule just given the volume A modification, called Nicholson's Hydrometer, is represented at 40° is to that at 60° as 500 is to 520. in the annexed figure. It is constructed of metal instead of glass, and the lower bulb is replaced by a small tray, E F,

As 500 : 520 : : 80 : 83.2.

ChI

less the range.

1

flint

1.063

8.900 | Coal

0 671

und

.

1.028

83-2 cubic inches then at 60° weigh 35 grains. We can now, fie. Dann ging ste hinaus zweimal am Tage auf den Hof by taking a second proportion, readily find the weight of 100 zee. Dan ghink zee hỉn-ouss' tswi'-mahl am tah'-gai ouf dain ho'r cubic inches.

unb streuete die Krümdyen hin, und die Vöglein flogen herbei As 83-2 : 100 :: 35 : 42.067.

dont shtroi'-ai-tai dee krü'm'-jen hin, dont dee föʻgʻ-line flo'-ghen herr-bi Now the same volume of air weighs 31.0117 grains. The spe- und picten sie auf. Dem Mädchen aber zitterten die Sande

40.067 cific gravity of the gas is, therefore,

dont pick-ten zee ouf. Daim meyt-jen ah'-ber tsit-ter-ten dee hen'-dai or 1:35.

31.0117 We will now append a table of the specific gravities of common vor Frost in ter bittern Kälte. belauschten sie die Aeltern substances. More extensive lists can be found in chemical and fore frðst in dair bit-tern keľ-tai. Dah bai-loush'-ten zee dee el'-tern other books. It may be well just to mention that sometimes 1000 und freuten sich des lieblichen Anblics und sprachen: Warum instead of 1 is taken as the specific gravity of water or air, the cont froi'-ten ziý dess leep'-li-yen an'-blicks dont shprah'-chen: Vah'-rööm only difference, however, is that the number is then a whole thust du das, Minna? number, instead of a decimal.

toost doo dass, min-na ? SPECIFIC GRAVITIES OF SOLIDS.

63 ist ja Alles mit Schnee und Eis bebedt, antwortete Gold • 19.250 Glass, crown 2.520 | Mahogany,

Ess ist yah ar-less mit shney dont ice bai-deckt, ant-võr-tai-tai Silver • 10-470

• 2.900*
Spanish

Minna, daß die Thierchen nicht finden können ; nun sind sie Copper

1.300 Cork

0-240

min'-na, dass dee teer'-yen niyts fin'-den kön'-nen; Doon zint zee Iron, cast 76248 Diamond 3:521 Ivory

· 1.917 wrought. 7780 Beeswax 0.960 Chalk

2.660* | arm, barum

füttere ich sie, so wie die reichen Menschen die armen Steel

7.820 Oak, seasoned 0-743 Granite 2-700* arm, dah'-room füt-tai-rai lý zee, zo vee dee ri'-yen men'-shen dee ar'-men Zinc 7.191 Elm

Sandstone

unterstüßen

ernähren. Brass 8.390 Beech

0-852 Limestone 2.650* 8ðn'-ter-shtat" sen dont err-ney'-ren. Tin 7.291 Fir 0 550 Marble

2-700*

sagte der Vater: Aber bu fannst sie doch nicht alle Platinum . 21-470 Ebony, American 1-331 Brick

2.000*

Dah zahdy-tai dair fah'-ter: ah-ber doo kanst zee doch niýt al-lai Lead 11-350 Pine, white 0.550 Portland stone 2:500*

versorgen! SPECIFIC GRAVITIES OF LIQUIDS.

ferr-zor'-ghen! Water 1.000 Nitric acid,

Spirits of wine 0·835 Die kleine Minna antwortete: Thun benn nicht alle Kinder Sea-water commercial. 1.500 Bloo1. 1.053

Dee kli’-nai min-na ant-võr-tai-tai: Toon den niýt al-lai kin'-der Mercury 13:590 Sulphuric acid, Turpentine 0880 Muriatic acid, commercial. 1.85 Milk

1•032 in der ganzen Welt wie ich, so wie ja auch alle reichen Leute commercial. 1.200 | Alcohol, absolute 0:79Olive oil . 0.915 in dair gan-tsen velt vee lý, zo vee yah ouch al-lai ri-yen loi-tai SPECIFIC GRAVITIES OF GASES.

Die armen
verpflegen? Der Water aber

blidte dic Air 1.000 Nitrogen 0.972 Marsh gas 0.559

dee ar'-men ferr-pfley'-ghen ? Dair fah'-ter ah'-ber blick-tai des Oxygen 1.106 Chlorine 2 470 Coal gas

0:46 Mutter de Magdleing an und sagte: 0 du Heilige GinHydrogen 0.069 Carbonic acid. 1.529

moot-ter dess meyyt-lines an dönt zahch-tai: odoo hi'-Li-gai ine's EXAMPLES.

falt! 1. A piece of silver wire weighs 95-2 grains. The flask filled with falt!

VOCABULARY. distilled water weighs 251-2 grains ; but when the wire is put in, it Wohlthäterin, f. bene- | Dem, dativem.and n. Arm, poor. weighs 337-21 grains. What is the specific gravity of the silver ? 2. A body weighs 871 grains in air and 357 in water: what is its

factress. (Wohl, to the.

Darum, therefore specific gravity ?

n. good; adverb, Mädchen, n.girl, maid. (dar-, instead of da-, 3. Required the weights of blocks of elm, limestone, and lead, each well, perhaps. Zittern, to tremble. there). measuring 10 inches * 6 * 3.

That, f. deed; Tha Bor, with, before. Ich, I. 4. An hydrometer, weighing 180 grains, requires 60 grains to sink it ter, m. doer, actor; Kälte, f. cold. Füttern, to feed. in water to the mark, when immersed in oil it only takes 40 grains. -in, aff, to form Belauschen, to watch, So, so. What is the specific gravity of the oil ?

feminine nouns; listen (be-, prefix, Reich, rich. 5. The same instrument requires 34 grains to be added when a stone is laid on the upper tray; but when removed to the lower, 4-5

thätig, doing, ac- as be in besmear, Mensch, m. man, huare needed. Find the specific gravity of the stone.

tive. sein, to be.) makes a verb tran- man being. 6. A piece of metal weighed 15 ounces in air and 13-08 ounces in War, was.

sitive).

Unterstüßen, to aswater. It was then attached to a piece of wood, and the two together Kalt, cold.

Lieblich, lovely (-licy, sist (unter, under; weighed 18-3 ounces in air and 11-46 in water. Required the specific Sammeln, to gather. affirmative, -ly, Stüße, f. prop). gravity of the wood.

Einzig, only.

ous, -able, -like). Ernähren, to feed, 7. 48 pounds of copper are mixed with 27 pounds of zinc. Find the Tochter, f. daughter. Anblic, sight support. specific gravity of the compound.

Aeltern, Gltern, pa- (Blid, m. look; an. Doch, yet, however, rents, pl.

blieten, to look Nicht, not. ANSWERS TO EXAMPLES IN LESSON III,

übrig, over.

at).

Versorgen, to supply, 1. Its specific gravity is 2656.

103

Bleiben, to remain, Sprechen, to speak. provide (Sorgen, 2. The specific gravity of the liquid is g, or 1.3125.

stay.

Warum, wherefore to care ; ver- pre3. The water in the flask weighs 165 grains, while the same bulk of Bewahren, to preserve, (-um, for, about). fix, for, before, &oil weighs only 140 grains. Its specific gravity is, therefore, ide, or keep.

Thun, to do.

way, astray). 0.848.

Dann, then.
Du, thou.

Denn, then, for. 4. It would be immersed either way •85, or lt of its depth. If the Behen, to go. Das, demonstrative Ganz, whole. 10-inch side is vertical it sinks 18 * 10, or 8! inches. If the other Sinaus, out.

pronoun, that.

Welt, f. world. side, the immersion is }. * 14, or 11% inches.

Zwei, two; Mal, n. 3ft, is.

Leute, pl. people. 5. The rope has to sustain 23344 pounds, or 1 ton and 943 pounds.

time.

Ja, indeed, yes, truly. Berpflegen, pflegen, to Tag, m. day.

(Es ist ja? is it support, to nurse. READINGS IN GERMAN.-II.

Hof, m. yard, court,

not ?)

Mutter, f. mother. farm. Schnee, m. snow.

f. servant, 2. Die Fleine Wohlthåterin.

Streuen, to strew. Fis, n. ice.

maid. Dee kli-nai vole'.tey-tai-rin.

Herbei, up (her-, hore, Bebeden, to cover. Heilig, holy. Es war ein falter strenger Winter. Da fammelte die

hither, indicates Taß, conjunction, Einfalt, f. simpli Ess vahr ine kal-ter shtreng'-er vin-ter. Dah zam'-mel-tai dee motion towards that.

city. fleine Minna, bie einzige Tochter wohlthätiger Aeltern, die the speaker). Nichts, nothing kli -nai min-na, dee ine'-tsi-gai todh'ter volo'-tey-ti-gher el'-tern, dee

Krümchen und Brosamen, die übrig blieben und bewahrete KEY TO EXERCISES IN LESSONS IN GERMAN. krü'm'-yen dont bro'-zah-men, dee 0"-briy bled'-ben ont bai-vah'-rai-tai

EXERCISE 79 (Vol. I., page 382). The different specimens of these vary considerably, tho numbers

1. Die nie zu ergründende Allmacht Gottes. 2. Ich bin hier, ansta given are therefore approximatious only.

meines Bruders. 3. Das Widerstehen der Polen war verzweiflungsvoll

m.

Magd,

füredlich hat Singen ihres Schlachtlicdes: ,, Noch ist Polen nicht verloren." | what yon would have done if you had been in my place. 3. If misfor4. Das Lesen lehrreicher Bücher vermehrt den Verstand. 5. 'Den Armen tune had not visited me, I should hardly have come to these opinions. beizuteben ist eine chriftliche Pflicht, 6. Der Wechsel der Zeiten und 4. He might have been happy, if he had known how to make use of the Jahreszeiten, und das Abseßen und Einseßen der Könige gehört allein der gatherer would have been lost. 6. If I had been able to come to you, I

opportunity. 5. If the water had carried the bridge away, the tollBorsehung an. 7. Gr vertheidigt diesen Mann, ohne ihn zu fennen. 8. Die should certainly not have remained here. 7. Great men would never have Gefahr erhöhte den Muth ter Soldaten, anstatt ihn zu beugen. 9. Der appeared, if they had allowed themselves to be kept back by difficulties Stüler lernt bas Zeichnen und Maler von seinem Bruder. 10. Diese and troubles. 8. If I had resolved to attain what I wished, I should Weise zu leben bekömmt mir nicht.

have had to work more diligently and perseveringly. 9. If he had EXERCISE 80 (Vol. I., page 383).

called, I should have heard him. 10. We will not go out, it might

rain. 11. If you would communicate to me some particulars about 1. Have you heard also that I fell from my horse 2. No, I heard these affairs, you would very much oblige me. 12. It would be my you had fallen out of the carriage. 3. History mentions that Tilly, greatest joy to see all men happy. 13. I must have been without who took Magdeburg in the Thirty Years' War, acted very barbarously, sense, if I had engaged myself in these affairs. 14. The shore has 4. My brother said you had been much praised. 5. Frenchmen assert vanished in the distance; O how I long to be in my fatherland! 15. If that they are the most educated people in the world. 6. Your sister he were as I wish (him), and if he had answered all my requirements, thought you had been in the town. 7. Englishmen are of opinion I should have kept him. that they are the masters of the sea. 8. This traveller said he had been twice at Rome. 9. He hopes he shall be at Dresden in a week.

EXERCISE 85 (Vol. I., page 403). 10. You fear you have been too slow in acting. 11. We thought you 1. Wäre Ihr Freund nicht unwohl gewporten, so würde er gewiß tas Fest were in the country. 12. I think we should have come to you yester: durch seine Gegenwart verschönert haben. 2. Wenn Sie Flüger wären, so day if the weather had been finer. 13. I thought he had been mindful wūrben Sie diese Unannehmlichkeit nicht erfahren haben. 3. Ich würte of his parents' warning voice. 14. He told me indeed he was ill, but Ihr Geschäft in Ordnung gebracht haben, wenn Sie es mir gesagt hätten. many declare it was dissimulation on his part. 15. His relations say 4. Sein Bruder würde besser empfangen worden sein, wenn er Empfehlungs his prosperity has brought on his misfortune. 16, I heard with re. gret that you had had the nervous fever. 17. Being up-stairs (in the briefe gehabt hätte. 5. Er würbe bessere Freunde haben, wenn er ange: upper room), I did not hear you call. 18. They say the Hungarian nehmer wäre. 6. Sie würden mehr Schwierigkeiten gehabt haben, wenn faithfully defended his country until his death. 19. I heard this young Sie dem Rathe Threr Freunde nicht gefolgt wären. 7. Ich würde nicht Frenchman would inherit a great fortune. 20. I believe that many den geringsten Zweifel haben, taß es Ihnen gelungen wäre, Hätten Sie Flüger people will have had their happiness here on earth.

gehandelt. 8. Wir würden nach Holland absegeln, wenn wir günstigen EXERCISE 81.(Vol. I., page 383).

Wind hätten. 9. Er würde der erste unter unsern Kaufleuten sein, wenn er 1. Man sagt, diese Herren feien betrunken gewesen, aber sie irren sich. 2. geselliger wäre. 10. Wenn ich die Macht gehabt hätte, so würde ich anders Man sagt, daß der Aufenthalt in Paris angenehmer sei

, als in London. 3. gehandelt haben, denn ich würde nicht so viel Geduld gehabt haben. 11. Wir konnten nicht glauben, taf dieses wahr sei. 4. Man glaubt allgemein, Was würde die Glüdseligkeit des Menschen sein, wenn er fein Glück der Feind habe die Grenze überschritten. 5. Er behauptete, daß es besser immer in fich selbst suchte? 12. Sie würden reicher sein, wenn Sie unter. wäre, zu bause zu bleiben, als auszugehen. 6. Ich wollte, daß er mit nehmender wären. 13. Wenn ich meine Börse nicht verloren hätte, würde mehr Liebe behandelt würde. 7. Gr sagt Jedermann, daß Sie ein sehr ich sie noch haben. 14. Er würde nicht so viel Geld haben, wenn er faut Teicher Mann seien ; aber wenn Sie es wären, so würden Sie nicht so spar, gewesen wäre. 15. Je grösser tie Schwierigheit, desto grösser ist das jam sein. 8. Haben Sie auch gehört, daß 3hr Freund vom Pferte gefallen Vergnügen sie zu überwinden. 16. Wenn er nicht über die Brüde gegangen fei? 9. Nein, aber ich habe gehört, er sei aus bem Wagen gefallen. 10. wäre, würde der Zöllner feine Bezahlung verlangt haben. u hoffe, Sie werden in vierzehn Tagen bei Ihren Eltern sein. 11. Ich

EXERCISE 86 (Vol. II., page 26). zweifle, daß er so unbankbar sein kann. 12. Dieser Fremde sagt, er sei 1. Can you not remember the day of my arrival? 2. O yes, I stil! freeimal in Indien, und auf seiner lebten Reise sehr frank gewesen.

remember it very well. 3. There are many people who are more disEXERCISE 82 (Vol. I., page 402).

posed to remember their bad than their good actions. 4. It was diffi

cult to convince him of the truth of this narration. 5. It is sometimes 1. Do you like to see my brother-in-law ? 2. Yes, I like to see

very difficult to believe what we cannot comprehend. 6. It is hard for him. 3. Uncle would like to see your drawings. 4. I like to have

the poor but industrious man to be obliged to claim the assistance of friends near at hand. 5. In my youth I was fond of studying, but now strange people. 7. The English language is more difficult to me than I take no pleasure in it. 6. He is fond of talking of his travels and

the French. 8. With his money, his relations, and his knowledge, it what he has met with 7. If you need the books, I will lend them to

was not difficult for him to obtain & good as well as an agreeable posi. you with all my heart. 8. He does not like to separate himself from

tion. 9. Why does your brother learn so much quicker than you? 10. his family. 9. I like a warm room. 10. Can you row us safely over

Because he has a better memory, and can retain the words better. 11. this stream? 11, No, we are not able, for this boat is too small. 12.

Can you not remember to whom you have given the books and the If you are able to translate these newspapers, do it. 13. As I under- paper? 12. I cannot remember anything about it. 13. The idler canstand the English language perfectly, I will gladly accept your pro

not remember the rules, because he does not thoroughly learn them, poral. 14. If he is able to do the work

well
, he may come to me; but if he and likes play better

than work. 14. Theft is a crime. 15. He placed is not able, it would be useless, 15. He did not believe that I was able a dollar in the poor man's hand. 16. We gladly remember friends at to execute all his commands. 16. If thou knowest how to govern all

a distance. 17. Young people sometimes wear spectacles in order to thy passions, thou art to be envied. 17. My friend Edward was so

appear learned. weak that he was not able to walk alone, and therefore he asked me to conduct him. 18. He thought no one was able to write on this rough

EXERCISE 87 (Vol. II., page 26). paper. 19. He was in want of money yesterday, consequently he 1. Erinnern Sie sich des Tages der Ankunft Ihres Freundes? 2. Ja, ich asked me if I would give him some. 20. It is true, he already owes erinnere mich des Tages sehr wohl. 3. Die meisten Menschen erinnern fich me several dollars; but as he was in need of the money, I gave him der Jahre ihrer Jugend mit Vergnügen. 4. Es giebt viele, die sich ihrer some, 21. No one is able to go out, because it rains too hard. 22.

Leidenschaften mit Scham erinnern. 5. Es ist schwer, alle Regeln einer He will soon be able to complete his work. 23. He cannot keep his Sprache zu behalten. '6. Es ist nicht so schwer, einen Gelehrten zu überword, and for the following reasons.

zeugen, ais einen Ungelehrten. 7. 38 eft schwer, fid, den Schidjalen des EXERCISE 83 (Vol. I., page 403).

Lebens zu unterwerfen. 8. Ja, es ist sehr schwer; aber te: tenkende Mensch 1. Wenn er nicht im Stande gewesen wäre, die Arbeit zu thun, fo würde überwintet fic. 9. Können Sie sich nicht erinnern, wem Sie mein Buch # fie nicht unternommen haben. 2. Wird er im Stante sein, sein Vers geliehen haben? 10. Nein, ich erinnere mich dessen nicht. 11. Lügen ist rechen zu erfüllen? 3. &r ist es nicht im Stande gewesen. 4. Wir soll. eine Sünte. ten nicht mehr verspreden, als wir im Stande sind, zu erfüllen. 5. Sind

EXERCISE 88 (Vol. II., page 27). Ste im Stante, eine bessere Erflärung von diesem Gegenstande abzugeben ? 6. 35 bin es wohl im Stande, aber ich habe jeßt feine Zeit. 7. Holt der himself. 2. If a person resolved to notice every speech, he would

1. He who does not esteem old people, is not worthy to be esteemed Anabe meinen Stoc gern? 8. Wenn er ex thut, so ist es ungern ; ich have to trouble himself about many things. 3. He was in want of the witte lieber selbst gehen. 9. Sehen Sie Ihre Verwandten gern 10.

means necessary to carry out his plans. 4. Who will take care of 3a, ich sehe fie gern. 11. Wenn Sie diese Bücher nöthig haben, so leihe me when I am forsaken? 5. When he repents of his faults, then it fie Ihnen gern. 12. Er hatte gestern Geld nöthig, deßhalb bat er mich, will I, too, think no more of them. 6. I should still need many more tab ich ihm einiges geben möchte. 13. Da Sie schon so viel schulden, so ist things, if I were not accustomed to dispense with articles which many

unnug, um mehr zu bitten. 14. Wer möchte nicht gern die Wunden people think indispensable. 7. The general mentioned your son as eines franfen Herzens heilen!

one of the bravest men in his regiments. 8. Grant me my petition, O

Lord, and protect me from my enemies. 9. Remember my petition. EXERCISE 84 (Vol. I., page 403).

10. Nothing is more insufferable than to wait long for some one, who, 1. I might have spared myself many an annoyance before now, at last, does not come at all. 11. I was anxiously waiting a long time if I had been silent instead of contradicting. 2. I should like to know for you, when I at last saw you come. 12. Take pity on the child

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RIVER.

that runs forsaken in the street. 13. If the prince were grieved called "primary,” or rocks first formed. They are supposed, for the people, he would govern differently. 14. But the people will as stated in the last lesson, to be the cooled product of the still reward him for it, and then not spare him. 15. It would be molten mass of which the earth was composed when it condensed indeed worth while to travel to California. 16. I should like to spare from the “fire-cloud.” However, it is but right to state that these clothes, if I had others. 17. I wish to die no other death than much diversity of opinion has existed concerning their origin, the death of decrepitude. 18. Do not forget my words, the pains that have been endured, but forget not the pleasures enjoyed. whether they ever were fused. This question will be alluded to 20. If the princes could, they would spare neither the liberty nor any in a future lesson on the Primary Rocks. pne right of their people.

The products of volcanoes, which are frequently found emEXERCISE 89 (Vol. II., page 27).

bedded in stratified rocks, are termed Plutonic, to distinguish 1. Sie pflegte ihres Vaters in seinem Alter und pflegte mich, da ich das Nervenfieber Hatte. 2. Er spottete meiner, und bemerkte nicht, wie die Menschen über ihn spotteten. 3. Hat er mein Geschenk angenommen? 4. Nein, er sagte mir, er bedürfe dieses Geschenfes nicht. 5. Erwähnen Sie nicht seiner Güte. 6. Der Lehrer barf der Nachlässigkeit und Unwahrheit seiner Scüler nicht schonen, sondern muß fie strenge verweisen, wenn er jene wahrnimmt. 7. Vergeßt nicht die warnende Stimme eurer Eltern. 8. Gedente del Sabbaths. 9. Wer kann einem Menschen glauben, der über alles (pöttelt, und der Zetermanns spottet. 10. Wir erwarteten mit Sehn

Fig. 1.-1. GRAVEL. 2. SAND. 3. MUD. fucht die Ankunft unserer Freunde. 11. Wenn du deine Fehler bereuest, dann them from the members of the primary groups, which do not werde ich mich deiner mit Freuder erinnern. 12. Gewissenhafte Leute Halten seem to have been the result of volcanic action, but are due to keine eiteln Reben, noch brüsten sie sich mit Eigenschaften, welche sie nicht a much more universal agenoy. befißen.

The various positions in which rock strata appear, the mode EXERCISE 90 (Vol. II., page 62).

in which the all but universal disturbance of strata has occurred, 1. I am unaccustomed to such work, and should not do it if I were and the manner in which igneous rocks-primary and Plutonic not in want of money. 2. I am in want of a great sum of money ; do -have been injected through the strata, as well as the explanahelp me, I am certainly not unworthy of your assistance. 3. If he tion of the technical geological expressions, will be at once were mindful of my kindness, he would not act so. 4. This man is so comprehended by studying the diagrams in this lesson. bad, that I consider him capable of any action. 5. Do you think the

The simplest form of deposition of strata is that which is covetous man can enjoy his life ? 6. I shall really be willing to confess taking place at the bottom of lakes. Here there are no my deed, only let me go! 7. The hunter was so sure of his prey, that disturbing currents, no eddies, no tides, and the only cause 8. Let me go now, I am heartily tired of your gossip. 9. Well, if you which could in any way modify this uniform distribution of are tired of me, I will go. 10. Never will I be guilty of a deed which débris (waste or worn material) brought down by the river would would render me unworthy of your friendship. 11. I possess a farm, be the state of the river itself-whether it were flooded or not. but being unaccustomed to working, and unacquainted with agricul. The nature of the sediment must entirely be determined by the ture, I am tired of it. 12. One is worthy of the other, but one is also mineral character of the rocks of the country drained by the often unworthy of the other. 13. A king who does not love his people is river. For instance, the colour of the Mississippi is not the unworthy of the throne. 14. Although you suspect me of the deed, still same as that of the Arkansas and Red River. The mud which I cannot confess it, because I have not committed it. 15. If men the Indus brings down is of a clayey hue, while that of the wicked deeds. 16. Help thy neighbour, and ask not if he is worthy of Chenab is reddish, and of the Sutlej paler. So that from the thy help, when he is in want of it. 17. I will accompany you, for I am deposit of a river the geological character of the country it acquainted with the road, and see you are unacquainted with it. drains may be determined. From the sediment with which the 18. I thank you, sir, I am not in want of your service; for as I am Nile fertilises Upper Egypt the nature of the distant mountains, tired of walking and weary of riding, I shall remain here. 19. In whose melting snows feed the flooding river, is plainly indicated. America, what does the man do who is not accustomed to any kind of The débris carried down by a river may be conveniently work? 20. He must become accustomed to work, and be mindful of divided into three classes of matter--(1) gravel, which is composed the adage—"He who does not work shall not eat.”

of water-worn pebbles; (2) sand, which is of the same material as

the pebbles, but in grains; and (3) mud or silt, which is a further LESSONS IN GEOLOGY.-II.

subdivision so as to render the particles impalpable of such

sediment is clay composed. It is evident that the gravel, being STRATIFIED ROCKS--UNSTRATIFIED ROCKS —STRATA-DE- the heaviest, will be deposited nearest to the embouchure of

POSITION OF STRATA-DIP OF STRATA-CLINOMETER. the river, the sand would overlie this, while the mud would be A VERY casual acquaintance with the appearance of the rocks carried far out into the still water, and gradually settle to the which compose the surface of the earth will be sufficient to bottom. This is depicted in Fig. 1. induce the observer to divide them into rocks stratified and It is evident that upon the occasion of an extraordinary unstratified. Stratified rocks-as the derivation of the word flood in the river the gravel will be larger, and will be carried indicates (stratum, " that which is spread out")-have the appearance of having been laid in layers one above the other. B

C

D Sometimes these layers are horizontal and perfectly flat. This is notably the case in the vast plains of Russia, where some of the very earliest deposited rocks—the Silurians—have retained the position in which they were formed for ages, notwithstanding the repeated and often violent changes which have in other regions affected the earth's crust. Most frequently, however,

Fig. 2. the strata exhibit flexures, and are more or less inclined to the further-so will the sand, which will be coarser, and will en horizon; in some cases-as in the coal measures in the Mendip croach on the area hitherto covered only by nud; thus we Hills, in Somersetshire-they are even vertical, and instances are able to account for those layers of coarse grains which are not wanting in which they have been absolutely turned over. frequently appear in a sandstone. Let the reader carefully

Abundant evidence is given to show that all rocks exhibiting scrutinise the stones of a wall, and he will at once find many stratification have been deposited by aqueous action—that is, examples of this. The area of deposition in a lake is neces. that their particles were once mixed with water, and gradually sarily very limited, hence the strata formed cannot be extensive, sank to the bottom of the sea or lake, where, in process of time, but where this process goes on in the sea enormous tracts are they became solidified, and appeared on the surface, either by covered with sediment. For example, the waters of the Amazon the draining off of the water or by the elevation of the bed. colour the ocean for a distance more than 300 miles from land;

Unstratified rocks are those which appear in amorphous masses that is, there is a layer of sediment now being deposited which (a, without, and morphe, form), that is, which exhibit no marks in after ages may appear as a vast horizontal stratum. of stratification. Granite is a well-known specimen of such Though all aqueous rocks must when deposited have been rocks. If excavations on the earth's surface be carried deep horizontal, yet when uplifted to the surface they submitted to enough, these rocks are invariably reached — hence they are various kinds of disruptions and displacements, and not only

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Bo, but the surface of the earth need not be uniformly level, even an interstratified igneous rock. The molten matter was ejected where the strata yet remain in their horizontal position. Thus, in over the floor of the ocean at a time when sediment was in the Fig. 2, the river, a, has worn down and carried away six layers of course of deposition, strata accumulated over this mass, and strata, and is in the act of cutting into the seventh. A similar then another eruption broke through e and its overlying strata, action has denuded the country to the right of the hill, c, which is pouring out another layer of unstratified rock; when the whole thus composed of strata still in their original position, and which was raised from the ocean bed and submitted to the denuding are found in a corresponding position on the hill, B. After action of water, the hard bed preserved the softer underthe denudation had been completed in the neighbourhood of d, lying strata; the water having but little action on E, left it an upheaving force tilted the strata, throwing them out of their exposed, running along the side of the hill as a terrace. It often position and producing a hill, by very different means from those happens that several of these igneous layers thus appearone above to which c owes its existence. The valley formed by the river

the other, and for this reason have between the hills B and c would be styled a valley of denudation.

acquired the name of trap rocks (from When the subterranean force acts upon strata which has not

the Swedish word trapp, a stair). room to obey its impulse, the strata become crumpled as easily

At F is shown a smaller fissure, as the leaves of a book borne down by a weight upon their

whose ramifications pass through edges. This phenomenon is illustrated in Fig. 3, where the

stratified and unstratified rocks. sedimentary strata abut upon the granite mass A, at B; the

Such fissures are usually filled with contortions are numerous, but many instances no less remark

mineral ores; they then are called lodes (from the Saxon lad, a course)

and veins. Fig. 5.

The irruption of igneous rocks

necessarily produces dislocation of the strata through which they pass; when the angle of the dip alters, as at a, a fault is the result. But if the continuity of the strata be broken, as at B, then a slip is said to have been caused. These faults and slips are of vital importance to the miner, as sometimes the seam of coal or the metalliferous vein

has slipped practically beyond his reach. Fig. 3.

The facts which have now been described are applied to able are known; one is well exposed on the Rhine, where draw geological sections of countries and localities in the followthe Drachenfels wall in the river. At c, the whole series of ing manner. It is impossible to trace a bed of rock through strata has bent in accordanoe with the pressure, forming a the whole of its development; we meet with it here and there saddle-back or anticline (anti, opposite, and clino, I bend), be.

-at the sea-shore—in a railway cutting-in a quarry, or in cause the strata dip in opposite directions from the summit of some ravine where a stream of water has worn its way; at the hill on whose crest runs the anticlinal line. The Swiss these different points we take its bearings, and then complete Jura may be quoted as a specimen of the formation sketched the section from our knowledge of the general flexures which at c. These mountains are composed of three such anticlines strata undergo. running in parallel ridges. The valleys between B and c and The observer must carry with him a compass and a clinometer. C and D would be called valleys of elevation. At D the strata This latter instrument may be a quadrant of cardboard, the edge would be said to outcrop. If the outcrop be a bluff

, bold cliff, of which is divided into 90 degrees. A piece of slight wood is it is termed an escarpment. The angle which the direction of fastened with a pin to the angle of the cardboard, which is placed the strata makes with the horizontal line is called the dip in the direction of the dip of the strata by the eye ; a plumb-line, The line of the outcrop is termed the strike, that is, the direction also attached to the pin, will show when the upper edge of the of the face of the hill as seen from the plain E. It is necessary clinometer is horizontal. The angle between this upper edge also to determine not only the angle of the dip, but the direction and the rod is the dip of the strata. A clinometer is given in of the dip, which will evidently be at right angles to the strike ; Fig. 5. They may be bought with a compass attached to them that is, if the strike run north and south, then the direction of and a spirit level, so made as to fold together into a small space. the dip will be east and west.

Thus provided, the expedition may be commenced. The notes When strata lie evenly upon each other and parallel, they are of the observations are registered, as in Fig. 6. The observer is said to be conformable ; but when such an instance as E occurs, where the overlying strata are not parallel to those beneath, but

45° have been deposited after the disturbed strata had assumed their new position, they are then said to be unconformable.

It may easily be imagined that sometimes the strata is too brittle to permit of a bend such as c, it then breaks on the crest of the ridge; this cleft becomes water-worn, forming a valley running along the top of the mountain. An example of this is also furnished in the Jura range. The modes in which the unstratified rocks are found asso

B

C ciated with those of aqueous origin are either in disrupting, interstratified, or overlying masses.

Fig. 6. In Fig. 4 the strata has been opened at c, and the fissure

guided by his compass to walk along the same direction, say from south to north. He finds the strata at a dipping southwards at an angle of 25°; a few miles further, after passing the crest of a slight eminence, the strata is again exposed at B in a quarry, and here the dip is changed to northwards and the angle to 30°. Again at c an observation is made, where the dip is southwards, and the angle 20o. Hence between B and c the

strata evidently form a basin, the steeper side being at B. At Fig. 4.

D the dip is again northwards at a small angle, when suddenly at e the azgle is greatly increased, while the direction of the

dip remains the same. This could only be accounted for by filled from below with molten rock. This was much harder supposing that somewhere between D and E the strata had been than the stratified rocks around it, which succumbed to the dislocated, and a fault produoed. action of water, and became degraded, leaving the mass of hard From these observations the section represented may be igneous rock standing out of the ground like a wall; hence such drawn. The three parallel lines at A, B, C, etc., indicate the phenomena are termed dykes. At E is figured a specimen of direction of the strike.

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