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weight, the flexure will altogether disappear, and the string will be straight line cannot be drawn in the latter in every possible direc. accurately a straight line." In this extract, it is plainly supposed tion, whereas in the former it can. A straight line cannot be drawn that the two points between which the “ flexible string" is pulled on the surface of a spbere ; it may be drawn on the surface of a in opposite directions, are placed in a horizontal position ; if at cylinder or cone in one direction, but not in every possible directhese points, pulleys were placed and the string made to pass over tion. both with heavy weights balanced at each extremity, it can be
QUESTIONS ON THB PRECEDING LESSON. shown by the laws of mechanics, that the string could never be Give Dr. Simson's explanation of a point ; of a line; of a surface; made to assume the horizontal position, until the weights were in and of a solid. What is defective in Euclid's definition of a straight creased to infinity; indeed, Dr. Whewell, in an early edition of his line? What is Playfair's definition of a straight line, adopted in “ Elementary Treatise on Mechanics," has added the following Dr. Thomson's edition? Give some idea of the attempts to deduce curiously-worded corollary to a problem of this kind :
the definition of a straight line from physical notions. Why does · For no force, however great,
a flexible string over pulleys placed in a horizontal line, and
stretched by equal weights at each end, fail to represent a straight Can stretch a cord, however fine,
line? What is the definition of a straight line given by Plato and Into a horizontal line,
Proclus ? What is the definition of it given by Archimedes That is exactly straight.”
What is the improvement made in this definition by Mr. Hill ? But what learner is able to enter into the spirit of this illustra
(To be continued.) tion, without a much greater knowledge both of geometry and mechanics, than he can be supposed to have at the commencement of his studies ? Is it necessary to go thus far for an explanation of a straight line? With all the above learned dis
LESSONS IN LATIN. No. XVIII. cussion, the said “ flexible string," would not be, as the writer
By John R. BBARD, D.D. strangely says, “accurately a straight line;" it would not in fact, be a geometrical line at all, however straight. Several other
REGULAR VERBS. definitions of a straight line have been proprised, all of them
THE FIRST CONJUGATION. more physical than metaphysical, that is, more dependant
ACTIVE VOICE. upon our notions of sensible objects, than upon our mental con
EXAMPLE.-- Amo, I love. ceptions or abstractions. Plato, and long after him, Proclus, a
Chief Parts ; amo, amávi, amátum, amáre. commentator on Euclid, defines a straight line as that which viewed
Characteristic letter, A loug. throughout its wbole length from one extremity to the other, appears simply as a point. This is a very clever and ingenious de.
PARTS WITH THE CORRESPONDING ENGLISH, finition ; but here, you fancy you see a fellow taking up a straight
SUB. PRES. IND. IMP. SUB. IMP. line in his hand and looking at one end of it, in order to see along Latin.
amában amárem the whole of it to the other end of it, as if it were a ruler, or straight English. I love
I may love
I did love, I might piece of iron. The definition of Archimedes, the prince of ancient
I do love.or mathematicians, is generally considered the best; viz., “A
I un loving
I was loving. straight live is the shortest way or distance between two points."
II. FUT. Every one knows and understands this definition ; it is the meta
amávero physical reason of the practical fact which occasions the formation
English. I shall or
I shall have of so many footpaths across our fields from one place to another.
loved Men reason and act geometrically, without giving their actions the
IND. PERF. SUB. PERF. IND. PLUPERP SUB. PLUPERT name of geometry. So do bees, as we shall see further on; but
amáverim amáveram amavissem these do it by insti.ct; those hy reason. Still, even this definition
I may have I had loved I might have is defective, great as its author really was, both as a mathematician English. I have loved
loved and a philosopher. The defect is, that it does not apply to an in
INF. PRES. definite straight line, any more than Euclid's; it is fixed between
Latin. amáre two points. Hence the necessity of Euclid's first postulate. This
English, to love defect was removed by an ingenious friend of ours, whose original
II. SUP. PART. PRES. Fot. PART. Act. views of many subjects shine forth more fully developed in those of
Latin. amátum amátu
amans the well-known and eminent sons he has left behind him; we mean
amatúrus English, to love
to be loved
about to love the late Thomas Wright Hill, Esq. * of Birmingham. To him are we indebted for the complete definition of a straight line which we
GER. GER, INF. PERF. have added to Euclid's; viz., " A straight line is that in which, if Latin. amandi amando amandum amando amavisse any two points be taken, the part intercepted between them, is the English, of loring to loving loving by loving to have loved shortest line that can be drawn between those points."
IMP. The definition of a plane superficies is due to Dr. Simson; for he
Latin amatúrum esse says, " instead of the definition as it is in the Greek copies, a more
English. to be about to love love thou distinct one is given from a property of a plane superficies, which is manifestly supposed in the Elements,- viz., that a straight line
Before I proceed I will explain these contractions : drawn from any point in a plane to any other point in it, is wholly Contractions. IND PRES.
SUB. PRES. in that plane.' In the edition of Euclid above referred to, this Explanation.- Indicative Mood, Present Subjunctive Mood, Present definition is ascribed to Hero of Alexandria, and it is added that
Toise. Plato defined a plane surface to be one whose extremities hide all Contractions. IND. IMP.
SUB. IMP. the intermediate parts, the eye being placed in its continuation. Explanation.- Indicative Mood, Imperfect Subjunctive Mood, Imper. Euclid's definition of a plane superficies was similar to that of a
Ject Tense, straight line given by him,-viz., that which lies evenly between its
Contractions. I. FUT.
IND. PERF. lines or boundaries. This, of course, is more objectionable even
Second Future Indicative Mood, than that of a straight line. Why it is so we leave to our ingenious Explanation.-— First Future
Tense. students to find out.
Perfect Tense. In conclusion, we add that a plane super. ficies may be more correctly defined as that in which, if any two
IND. PLUPERF. straight lines be taken, the part intercepted between them, is the least Explanation.- Subjunctive Mood, Perfect Indicative Mood, Pluparsurface that can exist or can be supposed to exist between those lines.
Contractions. SUB. PER.
fect Tenge. The distinction between a plane and a curve surface is this, that a Contractions. SUE PLUPERF.
Explanation.--Subjunctive mood, Pluper- Infinitire Mood, Present * The father of Rowland 111, Esq., the inventor of the Penny Pestage
Tense. scheme; of M. D. Hill, Esq., Q.C., and Recorder of Biriningham; of
Contractions. INF. PERT,
Contractions. I. SUP.
PRES. PART. These departures from exact correspondence, precision, and Explanation.-First Supine. Second Supine. Present Participle. uniformity are certainly drawbacks; but, notwithstanding Contractions. FUT. PART. Аст. .
these drawbacks, great aid may be derived from a careful and Explanation.-Future Participle, Active Voice. The Gerund.
systematic attention to the system here set forth.
I have said that these signs are applicable to all verbs. If Having in the above corresponding parts given the Latin as so, they need not be repeated. And in general the statement well as the English of several members of the verb, I need not is correct. You will, however, bear in mind what you have repeat them. I supply in full what remains. As I write for previously learnt as to the tense-endings, and the mood-end. young men and women rather than for children, I omit adding ings; and then you will remember that instead of bo,--am, the English in all the detail of the persons; for when you (es, &c.) is the ending, and as the ending so the sign of the first know what is the first person, you will readily supply the rest ; future of the third and the fourth conjugations. One or two thus, if the Engli-h of amaveram, the first person, is I had other deviations will occur to you. loved, you know that the English of amaveras, the second person, is thou hadst loved, and of amaverat, the third person, he
MOODS, TENSES, &c. of Amo, I love. hu loved; so also in the plural.
Indicative. Subjunctive. Imperative. Infinitive. Participle. Instead of I might have loved, the sub. pluperf, may some
amd-re times be rendered (put into English) by I would, I should, or 1
ama or amá-to could have loved.
amd-to In the corresponding English words, I have given the nearest approach to the several Latin parts. The student will do well
amé-mus to adhere strictly to these meanings at the first, though, as
amé-tis and-te or ama
ama-nto the correspondence between the several Latin and the several
(tóte English parts is not entirely complete and constant, he will
amá-bam find occasions when his Eglish will appear scarcely idio
amá-bas matic, or strictly proper. He cannot, however, learn too soon, amá-bat amd-ret that in few particulars are any two languages exactly correspondent. Accordingly, for amo, I have set down what may
ama-batis ama-retis be termed three meanings, --namely, I love, I do love, and I am
ama-bant ama-rént loring. Here, it is obvious that the English is more rich than the Latin, inasmuch as it has three forms of the present tense
ama-trum indicative mood, while the Latin has but one form. Having
amd-bit but one form, the Latin cannot by a form indicate the variations of the English present tense. Consequently here is a
ama-bimus want of strict correspondence; and here also is a source of
amd-bitis doubt; for we may ask, what is the English equivalent of
amá bunt amo: is it, I love, or I do love, or I am loving? After these remarks the student will know that it is with
ama-(0) some latitude that he is to take these
ama-(vi)sti* amd-(ve ris
amá-vit amd-(ve)rit CORRESPONDING LATIN AND ENGLISH SIGNS. IND. PRES. SUB. PRES. IND IMP. SUB. IMP. I. FUT. II. FUT.
amd-vimus ama-(vé)rimus Lat.
ania (té ritis bam
amd-(ve)ram ISD. PER, SUB. PER. IND. PLUPER, SUB. PLUPER. INF. PRES.
amá (ve)ras ama-(vi)sses Lat. erim iseem
amd (tebrat ama-(vi)sset Eng. have
might have INF. PERF.-Latin. isse English, to have.
Cama-(ve)rámus ama-(vijssemus IXF, Fur. IMP. I. SUP. II, SUP, PART. PRES. FUT. PART. ACT.
ama-(ve brátis ama-(vi)ssétis
amá (ve)ris Give yourself a thorough practice in these signs. Again
amd-(ve)rit and again ask, until you are perfect, what is the English sign of the indicative mood present tense? what the Latin sign?
Camd-(vé)rimus what is the Latin sign of the sub. pluperf.? what the English sign of the same? So go through all the parts.
amá-(ve)rint I hope you understand what I mean by these signs. Your
1. ama-tum understanding of them is the more important because they
Dat. ama-ndo pertain not merely to the verb amo, or to the first conjugation, GERUNDS.
Aco. ama-ndum but to all the verbs; and because, when you are perfect in
2. ama-tu your knowledge of them as just given, you will easily put Latin into English and English into Latin. On the account EXAMPLES.-Like this model, conjugate laudo 1, I praise; of this importance, I will subjoin a few explanations.
curo l, I take care of ; voco I, I call, These signs, then, might be called a set of equivalents, and
Compare together the II, Fut. with the Sub. Pres. You will I might have indicated them after this manner :
find that the endings are the same, except in the first person, i have
which in the former is ro, in the latter rim. In other words, bo will
the Latin language has no distinctive form beyond the first erim
person for one or the other of these tenses, A distinction is These signs or equivalents are, you see, without any verb. attempted with the aid of the accent or the quantity. Thus They are so given because they are applicable to all verbs. the first person plural of the second future is sometimes proTous to i you prefix the stem amav, and make amuvi; so tonounced long, as amaverímus. But the authority for this is hare you add I and loned, and make the corresponding Eng. not uniform, and consequently you find the sign of the long lish, that is, the English equivalent of amavi,-namely, 1 have and the sign of the short vowel thus over the i; denoting ured.
that the vowel is sometimes pronounced with and sometimes In some instances the English sign is arbitrary, or the best without the accent. we can get; in the ind. pres. love is chosen as the E.S. (Eng
* Ama-(ri)sti pronounced amavístíg as one word; the vi is put in brackets lish sign) for the want of a better. Scarcely less arbitrary is to denote that it may by syncopation (shorteninn) be omitted; as afterthe E. 8. of the imp., --namely, did.
There is a difference between the first future, amabo, and I like two walls ; and its upper surface also hardens, so as, with the future formed with the aid of the future participle, thus, the two sides, to form a kind of tunnel through which the amaturus sum. Amabo means I will or shall love, simply in burning or incandescent matter flows. dicating a future act, without determining when, or the precise This peculiarity of the walls of a lava current is well known point in the future when the act will take place. Amaturus in Italy, and by this knowledge men are able to deflect the sum signifies I am about to love,- that is, I shall shortly love; burning stream, and to turn it aside from its intended course. intimating that the action signified in the verb is near at hand, The people make a gash in one of the hardened sides of the is in the immediate future.
current. At this gash the lava will issue out, and discontinue Of the first future there is properly no subjunctive tense ; the course which it threatened to take. By this method many the import, however, is expressed by combination, thus, villages and towns have been saved from the destruction which amaturus sim (sis, sit, &c.), I may be about to love ; amaturus menaced them. An instance of this took place in Italy a few essem, I might be about to love. The second future also is with years ago. The people of Campania saw a current of lava out a subjunctive mood.
descending from Vesuvius which was likely to overwhelm their EXERCISES.--Form according to the model now given, that hamlet. They immediately went up to meet the fiery stream, is, write them out in full, with all the parts in both Latin and attacked it on the side farthest from their direction, and turned English, these verbs,-laudo I, I praise ; vigilo 1, I watch; the current towards Paterno. When the inhabitants of Paterno compăro 1, I procure.
heard of this manœuvre, they took up arms, arrested the operation, and caused the burning tide to take its own course.
As such a hardened crust is a good non-conductor of heat, LESSONS IN GEOLOGY.-No. IX. the melted matter within it takes a long time to cool. The
lava which flowed from Etna in 1819, was, nine months after By THOMAS W. JENKYX, D.D., F.G.S.
the eruption, in a state sufficiently fluid or molten, to move at CHAPTER I.
the rate of a yard a day. There is an instance, in the same ON THE ACTION OF VOLCANOES ON THE EARTH'S CRUST mountain, of lava being in perceptible motion even ten years SECTION V.
after the eruption. This deserves your notice, on account of
a very remarkable fact, and a fact which may help to resolve ON VOLCANIC PRODUCTS, OR THE MATERIALS ERUPTED FROM
some difficult problems in the examination of ancient rocks. VOLCANOES.
In 1828 a large mass of ice, several hundred square yards The quantity of matter which volcanic fires abstract from the in extent, was found in Mount Ætna lying under a bed of lava, bowels of the earth, and throw up to the surface is enormous. which had covered it while flowing in a melted state. How It has been scientifically calculated, that a volcano has, in some could this be ? You can imagine that rain-water, or drifted instances, thrown up, even at a single eruption, more matter snow, might freeze into a glacier at the elevation of ten thouthan if the entire mountain had been melted down to yield the sand feet, which was the height at which this ice was found. supply. The question which must interest every geologist is, This bed of ice was formed in a large hollow, while the volcano " Where does all this mass of matter come from?"
was in a state of rest. But, when the burning lava flowed over Among the various productions of volcanoes may be enume- the ice, how is it that the ice did not meli? It is probable rated, gases, aqueous vapours, lava, minerals, scoriæ, stones, that the bed of ice had been previously covered by a thick ashes, sand, water, and mud.
shower of volcanic ashes. As such a layer of ashes is also a It is well known that volcanoes emit different kinds of gases, good non-conductor of heat, it prevented the ice from melting : such as muriatic gas, sulphur combined with oxygen or with and after the bed of lava had cooled over it, it continued to hydrogen, carbonic acid gas, and nitrogen, besides aqueous preserve the ice in an unmelted state. The truth of this theory vapours.
is established by facts which occur about Ætna in the present Several of the simple minerals, and some of the metals are day. In the higher regions of that mountain, the shepherds, found in the melted materials ejected by volcanoes, such as in order to provide a supply of water for their flocks during common salt, chloride of iron, sulphate of soda, muriate and summer, are in the habit of sprinkling beds of snow with a sulphate of potassa, iron, copper, lead, arsenic, and selenium. layer of volcanic sand, a few inches thick, and this is found to
The examination of these gases and minerals belong rather be an effectual means of preventing the sun from melting to chemistry than to geology. They are related to geology until it is wanted. only as they give aid in the study of the mineral character of The term scorix or cinders, is applied to the fragmentary rocks. From the very nature of such mineral productions it slags of lava which are ejected into the air, and then setule was to be expected that volcanic substances should greatly around the volcano. The structure of these cinders is owing vary in lithological character, from that of light ashes to that entirely to the influence of the external air, and not to any of compact and heavy crystalline rock. Nor is it a wonder special difference of material in composition. Whether lava that the quantity of mineral matter ejected is so great as it is, flows like a stream, or is thrown up in jets, it cracks and beespecially when you consider what a multiplicity of elemen- comes porous, as soon as it is acted upon by the atmospheric tary substances are acted upon by the fires below, and how gases. The result is, that the pieces or fragnients become these elements in their fused state, strive to combine with each cellular or vesicular,--that is, a mass full of small rouuded other in different ways and proportions. It has been ascer- holes, as may be seen in any specimens of pumice and lava. tained that, within three square miles around Vesuvius, more If lava is cooled under great pressure, it becomes compact, and specimens of the simple minerals have been found than on any even crystalline as in trap, trachyte, &c. other spot of the same dimensions. Of the 380 different species During an eruption, masses of stone are frequently thrown of minerals known to the celebrated Haüy, 82 had been found up into the air. Where do these stones come from, and come on Vesuvius alone.
unmelted? When the little islet, called Graham's Island, rose Lava is a name given to any mineral matter melted in a in the Mediterranean, near the coast of Sicily, in 1831, ilk volcano, and ejected in a stream over the rim of the crater. crater ejected pieces of dolomite rock, and fragments of limeWhen the molten lava is consolidated by cooling, it receives stone; and also masses of some pounds weight of Silurian sock. fresh names, partly according to its mineral composition, and In the awful eruption of Tomboro, in Sumbawa, an island in partly according to the slowness or rapidity of its refrigeration. the Molucca group, which took place in 1816, stones fell very Hence such names as scoriæ, cinders, pumice, basalt, trachyte, thick-some of them as large as two fists, but most of them obsidian, &c.
only of the size of a walnut. In a museum at Naples, are The melted lava may be boiling for years within the walls exhibited specimens of the various stones which have been or cliffs of a crater, as has been represented in fig. 11 and fig. ejected from the crater of Vesuvius. Several of these specimens 15, without flowing over its edges. When lava swells above are fragments of the limestone which prevails in the district, the edges of a crater, and flows down the declivities of the hill, and these limestone specimens contain organic remains in them. it does not spread itself on all sides as a flood of water would, These specimens prove that the vent of the volcano goes lower but it moves in a tall half-rounded mass, not very unlike the down than the limestone bed, and that the melted matter engravings that you have seen of a tubular bridge. The sides thrown up rubs against the sides of this rock, rends and tears of this moving body of lovs hardon so as to form something portions of it off, and throws them up into the surface. These
limestone specimens are found to be impregnated with mag. gist in accounting for the bones and skeletons of extinct species nesia, an element which entered it while it was being heated of animals which are found in the ashes of ancient volcanoes, in this volcanic crucible.
such as are found in Avergne,ʻin France. In fig. 20, you see how the vent of a crater passes through Many naturalists think that it was by such a shower of various beds of rock, such as A, B, C, D, E, F, some of which ashes that Pompeii and Herculaneum were destroyed, and are fossiliferous, and others are of the more ancient class. The that this accounts for the perfect.preservation of even the most upper stratum, A B, is formed by the ejected matter which has fragile articles found amid those fossil cities. been thrown up on all sides from the volcano.
Some remarkable facts connected with the structure of these Besides stones, it is found that volcanoes discharge a vast | ashes deserve to be noticed. When Graham Island rose in quantity of ASHES,
the Mediterwhich darken the
ranean, in 1831, air for hours, and
Dr. Davy mensometimes for
tions a shower of many days, and
ashes which fell. which in their
In the substance fall occasion great
of these ashes, he damage to agri. Α.
found fibres like culture, and to a
vegetable fibre, villages and
and which had towns. These dry b
the smell of a and hot ashes are
burning sea weed. probably only C
This has led to the lara pulverised
conjecture that as or turned into
sea-water entered powder by frica
the submarine tion. It has been
volcano, fibres of conjectured by
weeds were some that they
sucked in with it.
0 originate in the +
There is another
t kind of bladdered f +
fact more remarkfroth which may
able still. On have once rested
Sept. 2, 1845, a on the surface of The vent of a volcano passing through various strata, and wearing away fragments
Danish ship was the incandescent
sailing in 61°north matter while cool. from the sides of the rocks.
luciuut, a thick ing under diminished pressure.
cloud was seen to approach the vessel from the N. W. in the These ashes are sometimes like impalpable powder, but, in direction of Iceland. The sails and the deck were immediately other instances, very heavy as a mass. During the eruption of covered with ashes. These ashes had come from the volcano, Tomboro, in Sumbawa, in 1815, the ashes which fell, were so Mount Hecla, which was in a state of eruption on that day. heavy as to crush and destroy several houses even at forty This volcano was 533 miles from the ship, so that the ashes miles distance from the crater. Also at sea, to the west of must have travelled at the rate of 46 miles per hour. The Sumatra, thou
famous Professor Ehren. sand miles off from Tom.
berg examined this dust boro, the ashes and cin
under a powerful microders fell so thick as to foat two feet deep on the
scope, and discovered
that it abounded in wellsurface of the sea, and
known siliceous organic render the passage of
bodies, and in well preships extremely difficult.
served shells or cases In other instances, the
of infusoria. This is a ashes were so light and subtile as that, notwith
fact of great importance,
as it helps us to account standing an awning made
for certain volcanic dust to cover the deck, they
found near extinct vollay in heaps of a foot in
canoes such as the Eifel, depth on many parts of
on the Rhine, the vessel, and several
There are volcanoes tons were thrown over.
which eject WATER, or board,
whose craters are filled The quantity of ashes
The greater discharged by volcanoes
part of the vapour dismust be immense. In 1835 there was an erup
charged by volcanoes is
purely aqueous. It is this tion of Cosiguiana, a
vapour when condensed volcano in the gulf of
by cold air that forms Fonseca, on the shores of
the springs which are on the Pacific. During that
the sides of volcanic eruption, ashes fell at
mountains. But, besides Truxillo, on the shores of
aqueous vapour, the Gulf of Mexico. Por
Mud volcanoes, as seen by Humboldt at Turbaco, in New Grenada. there are cases in which tions of this shower of
water is a volcanic proashes fell on board a ship twelve hundred miles westward of duct. It has been argued by many that water acts an importthe volcano, and four days later at Kingston, in Jamaica, 700 ant part in the eruptions of volcanoes, since, of 300 vol. miles eastward of it, having travelled in the air by an upper cur. canoes on the globe, two-thirds are situated in islands, and rent of west wind, at the rate of 170 miles a day. For about 30 the greater part of the other third are either on the borders of miles to the south of this volcano, ashes covered the ground the sea, or not far from the coast. There are, however, some three yards and a half deep. Thousands of cattle, wild animals, volcanoes, such as those in Mexico and in Central Asia, which and birds perished under the ashes. This fact assists the geolo- are very far from the sea,
Near Seminara, in Calabria, an earthquake opened a chasm blazed to a great height for three hours, Then, for about in which a lake was formed 1785 feet long, and 937 broad. It twenty-four hours, they continued to burn about three feet was called Layo del Tultilo. The inhabitants of the district, above the crater from which the mud was ejected. Near a from fear that the miasma from such a lake would be prejudi. village called Baklichi the flame rose so high as to be seen cial to their health, tried to drain off its waters by means of twenty-four miles off. Large fragments of rock were thrown canals. Their work prcvcd vain, for the lake was found to be to a great distance round. These, as we have seen in fig. 20, constantly filling from springs which issued at the bottom of must have been torn from the cavities of the strata beneath. the chasm.
At Damak, iz the province of Samarang, in the island of Java, In 1811 the volcanic island, afterwards called the Sabrina, there is a similar mud volcano, where the mud is of high temwas observed to rise from the sea near St. Michael, at the perature. At Girgenti, in Siciiy, and at Sassueto, in Northern Azores. Its crater shot up cinders 700 or 800 feet above the Italy, they are also found under the name of Salses. level of the sea. These cinders were followed by an immense column of smoke. It began to rise in June. On the 4th of July it was high enough above the sea to form an island about a mile round. In its centre was a crater full of hot water,
LESSONS IN ENGLISH. No. XI. which discharged itself orer one of the edges into the sea. One of the most singular products of a volcano is mud.
By John R. BEARD, D.D When the aqueous vapours from the crater are condensed by
DERIVATION: PREFIXES (continued). the cold atmosphere, heavy rains are produced, which fall upon Before proceeding further with these prefixes we may now expose the velcanic dust on the sides of the mountain, and form a current of mud called by the Italians “lava d' aqua,'
a common error. It is generally thought that words bave severa aqueous lava, an enemy much more dreaded than a stream of disconnected significations. Several significations many words melted lava. It is disputed by some geologists whether it was have, but these significations are all allied one with another. And nut by such a Hovd of volcanic mud, rather than by volcanic they are allied one with another in such a way that a genealogical showers, that Pompeii was destroyed. This, ? s, is only
connexion runs through them all. I mean that the second ensues mud on the surface of volcances.
from the first, and conducts to the third. The meanings of words In some volcanic districts mud is found to ooze occasionally flow from a common source like the waters of a brook. That frm the ground. Near Laureana in Calabria, the swampy common source, or parent-signification, is, in all cases, one that soil of two ravines became filled with calcareous matter, which denotes some object of sense, for objects of sense were named oozed out of their respective sides just before the shock of an before other objects. Our first duty then is to ascertain the physiearthquake was felt in that district. This mud flowing down- cal meaning of a word. From that meaning the other meanings wurd from both ravines, at last became united, formed one flow as by natural derivation. Those secondary or derivative stream, increased in force, and was a mud river 225 feet wide significations then can scarcely be termed meanings; they are not and 15 feet deep. In its progress it overtowed a flock of goats, so much meanings as modifications of the primary import of the and tore up trees, which it carried on its bosom like the masts
root. Certainly they are not independent significations . Thus of small boats. When the mud became dry it was reduced in viewed, words have not two or more senses, but in the several cases depth to about seven feet, and it was found to contain frag. the one sense is varied and modified. Even in instances in which ments of earth of iron colour,
opposite meanings are connected with the same word, the filiation I have now to call your attention to a real mud volcano, as may be traced, as both Jacob and Esau sprang from the same represented by Von Humbuldt, see fig. 21. Near Carthagena, stock. I will take an example in the word prevent. Prevent in New Grenada, South America, there is a high hill called means both to guide and to hinder, to lead to, and to debar from. Popa. To the south-west of this hill there is a village district The opposition is sufficiently decided. Yet these two opposed called Turbaco. In the midst of a thicket of palms is a meanings are only modifications of the root-sense of the word. marshy ground called Los Volcancitos. The tradition of the First I will exhibit the diversity and then explain it. Prevent, inhabitants is, that this ground was once all in flames, but signifying to guide, aid forward :that the fire had been extinguished by a monk who sprinkled
" Prevent us, O Lord, by thy grace.-" Book of Common Prayer." the place with holy water. Since then the fire volcano has
“ - Love celestial whose prevenient aid become a watery one.
Forbids approaching ill."
Mallet. The volcancitos are about 15 or 20 in number, stand in cones from 19 to 25 feet high, and measure around their bases from Prcvent, signifying to hinder, obstruct. 78 to 85 feet each. On the top of each of these volcancilos is an
“Where our prevention ends, danger beging." Carer, aperture or depression from 15 to 30 inches in diameter, and filled with water, through which air-bubbles are constantly either stop or moderation, must needy exhaust bis spirits."- Reliq.
" Which though it be a natural preventive to some evils, yet without escaping, as seen in fig. 21. In other parts of the ground Wottonianae. there are apertures for such escape of air, but which are not surounded by cones. The cones have, no doubt, been raised
" Physick is either curative or preventive; preventive we call that by the clayey inud contained in the fluids, and the dull sound, which preventeth sickness in the healthy.”—Brown, “ Vulgar Errors." which precedes every ebullition in the water of the cone, indi- “ Prevent us, O Lord, by thy grace," means" aid us forward.” cates that the ground is hollow. It seems that each crater « Preventive of sickness," signifies that which causes sickness not receives its supply of air and gas from separate channels. to come. There is the contrariety. Now for the explanation. These little craiers are always filled with water, even in the Prevent is made up of two Latin words,--namely, prae, before, driest seasons. The temperature of the water is not higher and venio, I come or go. Now, you may go before a person for than that of the atmosphere.
two opposite purposes. You may go before him in order to guide, These mud volcanoes originate with earthquakes, and their aid, and conduct him onward ; or you may go before him to bar up rise is accompanied with subterranean detonations and with his way, to hold him back, to prevent his advance. And as either jets of fame. Their diminished action supplies us with a of these two purposes is prominent in the mind of the speaker, so specimen of the perpetual though subdued activity of the in- the word is used by bim to signify, to guide, or to hinder. The terior of the earth. The niudy water seems at the first ebul proper meaning, then, of prevent is, to come before : bence, 1, to lition to have been of a high temperature, but afterwards the guide, or, as a natural consequence, 2, to aid ; or again, 1, to obtemperature becomes lower. This fact implies that the venis, struct, and as a natural con equence, 2, to stop, &c. And how the which at first communicated with devp-lying strata of great moral and spiritual imports conie out of the phy.ical, is also seen heat, have, by some means, become obstructed or choked up, in the diverse applications of the word ; for, as we have just read of and that the vents of the cooler water do not rise from any preventive medicine, so in divinity you may reau of " prevenient great depth below the surface.
grace." These mud volcanoes are found in different parts of the Toese remarks, illustrations of which occur in what bas just globe. In the Caspian Sea, on the peninsula of Abscheron, is preceded, and will occur in what is about to follow, may serve to situated the mud voicano of Jokmali. It was formed Novem- sbow you that language nust be studied genealogically. Indeed ber 27, 1827. At first flames sprang up from the soil, and every word has a history; and in the dictionaries, every account