In the previous pronouncing table, the reader will have remarked that two vowels, when i is the first, may come together in one syllable without constituting a diphthong. The reason of this is, that in such cases the i is not heard, or scarcely perceptibly touched in more measured enunciation, and only serves the purposes of an auxiliary letter, to denote to the eye that the preceding consonants c, g, or gl, in such combinations as cia, cio, ciu, etc., gia, gio, giu, etc., glia, glio, gliu, etc., are to have what may be termed the squeezed sound. The letter i is not heard, or scarcely heard, and why should it form a diphthong simply because in juxtaposition with another vowel? The same observation is applicable to such combinations as scia, scio, sciu, etc., pronounced shah, sho, shoo, etc. In all these cases a diphthong 13 seen, but not heard, or scarcely heard. And even three vowels in combination, when i is the first, may meet in one syllable without constituting triphthongs; because in such cases as well, is preceded by the letters c, g, and gl, not being pronounced, and only serving to denote the squeezed sound of these consonants. For example: libricciuolo (pronounced lee-brit-tchooô-lc), a small book; muricciuolo (moo-rit-tchooô-lo), a small wall; nomicciuolo (ooo-mit-tchooô-lo), a little man; giuoco (jooô-ko), a game; figliuolo (fil-lyooô-lo), a child, son; cavigliuolo (kah-villyood-lo), a little peg or pin. In these examples, the three vowel combinations, or, more correctly speaking, associations, are diphthongs, and not triphthongs; and it is only by confusion of signs written for the eye, with literal representations of sound, that grammarians have been led to class them as triphthongs. In taking this view, I venture to differ from many authorities; but I think I have shown reason for so doing.

i

on

I have now explained the elements of Italian pronunciation. Exceptions, philosophical reasons, delicacies, and refinements, I shall on future occasions explain in "additional remarks pronunciation; and any necessary further remarks that may be considered elementary, I shall likewise add from time to time. The remark that these explanations only contain the elementary principles of Italian pronunciation, will serve to show the student really desirous of acquiring a knowledge, and not 3 smattering, of Italian, the importance and necessity of following me closely and carefully throughout. The pace may be tiresome, but, if taken now, will spare much labour for the future. The ingenious reader cannot fail to have noted that the tables I have given are not expanded examples of words, bat systematic exercises, illustrating in natural order all vocal combinations, and thus giving an insight, from the very first, into the structure of the language.

It may be here seasonably remarked, that many persons in England learn Italian for musical purposes only. The system of pronunciation here given will be of peculiar advantage to them; for in singing Italian airs, and in reading the scores of Italian operas, nothing is so puzzling as the necessity of giving to one note what to the eye seems two, and sometimes even three syllables; and nothing is so hideous as to hear Mozart's or Rossini's music distorted by a failure to vibrate double consonants, by the neglect of the two e's and the two o's, by hard enunciation of the gn and gl, by improper syllabic distribution of vowels and diphthongs, etc.

Two more tables will finish my lessons on pronunciation, and satisfactorily initiate the student into the difficulties of this part of the language. In the concluding table I shall give a general mirror of the pronunciation, to which the student who may have a doubt as to the proper pronunciation of a word may always refer, and thus obviate the necessity of constantly imitating the pronunciation of words by signs throughout the

grammar.

I have already explained the importance of mastering the difficulty to foreigners of giving the proper vibrated sound to double consonants.

LESSONS IN GEOLOGY.—VII. EARTHQUAKES AND ALTERATIONS IN LEVEL. THE next phase of igneous action which we shall consider divides itself into two divisions.

(1) Earthquakes proper, that is, when the land is shaken by a series of upheavals and corresponding subsidences; and (2) the gradual change of level which the land undergoes, whereby those rocks which are formed on the bed of the ocean by aqueous action are elevated so as to become dry land, and again, those parts already above the ocean level are depressed, so that, in process of time, another layer of stratified rock is deposited on the submerged surface.

These two classes of action are most closely allied. In all probability, an earthquake is one of the results of the great igneous action which produces a change of level; that is to say, when the fluctuations of the temperature of the earth's crust cause the rocks to expand or contract, a corresponding alteration of level takes place in the surface immediately above the locality, which experiences a change in its temperature. When this process is rapid--which seems to be the exception and not the rule-and if, by any means, water finds access to the heated region below, a large generation of steam is the result, and a sudden shock is imparted by the explosion to the rocks in the neighbourhood. This is propagated on all sides from the centre of disturbance in a wave, which reaches the surface, and as it rolls wider and wider from its centre, causes all the phenomena exhibited in an earthquake, gradually decreasing in its power until it becomes imperceptible. Mr. Robert Mallet, C.E., of Dublin, very satisfactorily accounted for the earthquake motion on this supposition, following out the theory on mechanical grounds. The earthquake in South Italy in 1857 afforded him an opportunity of testing the truth of his conclusions, and he found observation fully supported his anticipations. A reference to the diagram (Fig. 11) will enable the reader to comprehend the process of earthquake disturbances.

FF is the surface of the earth. c is the point, it may be many miles beneath, where the explosion which caused the disturbance occurred. The shock would be transmitted upon all sides of c in a spherical wave. The lines do not represent a

succession of waves which can only take place when there are a succession of shocks, but the same wave in various positions. E c is the seismic-vertical. The effect of the earthquake in the immediate neighbourhood of E will be a vertical rising and falling, as if the ground had received a blow just beneath the surface. By the records of many earthquakes this motion appears to have been constantly experienced. The mode in which the wave passes along the surface is shown at F (Fig. 12), where it appears as a ripple running along the ground. The effect which this wave has on the objects built on the surface will be evident by considering the behaviour of the pillar at F while the wave is passing beneath it. In the diagram the pillar is thrown out of its perpendicular by the advance of the fore-slope of the wave. If it cannot bear this disturbance, it

falls exactly along the path of the wave. down as the wave passes underneath it, it dicular position as it stands on its crest. other way as it stands on its rear flank; turbance has quite passed, and the surface has subsided to its original level, the pillar, left by the wave, suddenly totters back to its perpendicular with a kind of jerk. This motion has a more destructive effect than that which first threw the shaft from its position; and if the capital did not fall off in the first instance, most probably it will be thrown off by the return of the pillar to its upright posture. In any case the line drawn from the fallen object to the base of that which supported it must be in the direction of the wave. By passing through the visited district, Mr. Mallet was enabled to map very many of these lines, and on their production he found that they all intersected within half a mile. Thus he determined the position of the point E (Fig. 13), directly under which was the centre of the disturb

ance.

To find the exact depth at which the explosion took place, observations of fissured walls were taken. It will readily appear, on inspecting the diagram, that if the wave moved in

If it be not thrown assumes its perpenThen it slopes the and when the dis

earthquake-waves. Then, again, these latter waves have different velocities in various rocks, and therefore the coseismal lines-that is, the lines which mark the emergence of the wave -are not always circular, but may extend much further in one direction than in another. Hence it happens that areas disturbed by an earthquake shock are frequently of very irregular shape. Varied and peculiar phenomena are recorded as preceding and accompanying earthquakes,

the direction of the line c s, the wall of the house, being bent by the emerging wave, would be fractured at right angles to its path. Therefore, a line perpendicular to the fracture would indicate the angle of emergence. This being found, the depth of the point c is at once given. In the instance of this Neapolitan earthquake, the centre of the disturbance was not more than seven or eight miles beneath the surface. The above statement is but a very crude outline of the subject, as so many disturbing causes interfere with the direct results. For instance,/ the origin of the shock may not be a point, but the disturbance may

It seems-from observations made on the principle above referred to-that the centre of disturbance was some eighty miles out at sea. The actual scene of the gaseous explosion must have been deep-seated, for the effects of the shock were felt over an area four times as

be distributed over an area. This has received confirmation by the loud rumbling subterranean noises, which sound as if a number of violent explosions had succeeded each other in vast cavities far in the bowels of the earth. These frequently precede the shocks, the sound-waves being able to travel faster than the

large as Europe. The water rose suddenly twenty feet in the West Indies. The great Canadian lakes felt the movement. In Scotland, Loch

Lomond rose
on one beach

more than two feet, the water not participating in the lurch

which the land

ex

gave. To the very north of Europe the waves of dis turbance tended. In six minutes 60,000 people in Lisbon perished. Many had col

lected on the

wide expanseof the new marble quay, out of

the way of the falling houses, when suddenly the quay, with its living crowd, sank, with many ships in the harbour, and not a body, nor the splinter of a wreck, ever rose up from the watery depth. We can only suppose that a fissure opened beneath the harbour, and after engulphing the whole, as suddenly closed.

In this earthquake a remarkable proof was offered of the fact above alluded to, that the wave is more readily propagated in some strata than in others. The destructive effect was confined to those houses which were built on the Tertiary strata. The lower part of the city, which rests on blue clay, was most severely shattered; whereas that part of the city which was built on the limestone or basalt escaped. The undulatory movement passed along the earth's surface at the rate of twenty miles an hour. The sea-wave rolled about four miles in that time. This wave is generally the cause of as much loss of life as the actual violence of the shock. This may well be sup. posed from the fact that at Cadiz the wave was sixty feet high. This wave is largest when the point of disturbance is under the sea; then the sea-bound towns are subject to a double inundation. The undulatory movement, when it reaches the shore, causes a great commotion, as, when a basin of water is moved, the water does not at once participate in the motion, and therefore washes up the sides of the vessel. This disturbance no sooner subsides than the sea-wave, which has followed the "ground" wave at a slower pace, rushes in upon the shore, its waters black with the sediment of the ocean-bed.

South America has for centuries been the scene of repeated earthquakes. A few years after Lima was first built, in 1582, the city was ruined, and since then the catastrophe has been repeated some twenty times. In all the cities of that neighbourhood the ecclesiastical year is full of anniversaries commemorating terrible overthrows or marvellous escapes. But none of these calamities seem comparable to that which has just paralysed the country. Two shocks, on the 13th and 16th of August, 1868, passed over Peru and Ecuador, ruining every town and city, and leaving between two and three hundred thousand dead to putrify in the tropical sun. Arica, a seaport town, was completely covered by the wave. The writer of these pages hears from one who survived that, upon the first shock, at 5.15 in the afternoon, he, with some others, jumped upon a barge, when the great wave carried them on its crest completely over the town above the spire of the church, and left them unharmed nearly a mile inland.

The chief geological effect of earthquakes is shown in the permanent alteration of the level of the land. In 1822 the coast of Chili was raised some two feet, while further inland the elevation was more than double this quantity. In 1855 the coast of New Zealand for ninety miles evidenced a rise of nine feet. (For many other facts illustrative of the alteration of level-a result of an earthquake-in all parts of the world, chap. xxviii. of Vol. II. of Lyell's "Principles " may be consulted.)

But that gradual alteration of level which is not accompanied by convulsive movements is more important than these local variations. It is difficult to establish these facts, because we have no standard which is not itself subject to alteration. Careful investigation of the coast of Sweden has shown that most of the Scandinavian peninsula is rising at the rate of four feet a century. The coast is favourable for the observation. There are no tides in the Baltic, and the cliffs descend perpendicularly into the sea; the water-level has been repeatedly marked, and the rise judged by its change. In few other places are the same advantages. Mr. Darwin has suggested an ingenious proof of the sinking of the ocean-bed in the Pacific. It is known that the coral insect cannot live below twenty fathoms, the pressure of the water beyond that depth being too great for its existence. How, then, can the fact be accounted for that many of the coral structures have their foundations resting on the ocean-bed at profound depths? There is only one reasonable solution of the difficulty, that they build upon a sinking foundation, and this very fact impels their labour and increases the demains they conquer from the sea.

We have reserved one well-known proof of this repeated oscillation of the earth's crust, that of the Temple of Serapis, near Puzzuoli, in the Bay of Naples.

The ruins of this temple consist of three pillars of marble hewn out of solid blocks. They are rather more than forty feet high.

The history of this remarkable temple seems to be this:From certain inscriptions discovered in the neighbourhood we learn that, in 105 B.C., a temple dedicated to Serapis existed In 1828 the handsome mosaic pavement of this temple was discovered five feet beneath that from which the pillars rise. The existence of this pavement indicates

on the sea-shore.

that the land must have sunk, and the present floor have been raised above the level of the water. In the early part of the third century, the Emperor Alexander Severus beautified the temple, of which these are the pillars.

The

At what time the temple was deserted we cannot conjecture; but in 1749 the following facts were brought to light by excavating:-That when the sea broke in, the salt-water caused a hotspring which existed to throw down a dark calcareous deposit, two feet thick; above this a layer of volcanic tufa reposed, which must have been ejected from a neighbouring volcano; this deposit is not regular, varying from five to nine feet in thickness. eruption seems to have formed a barrier which kept out the waters of the sea, so that the hot-spring continued to deposit its carbonate of lime, but without any marine admixture; thus about two feet more were added to the matter which embedded the bottom of the columns. More volcanic tufa was now placed upon the lime deposits, either by a storm or another eruption, making a total deposit of eleven feet. All this time the land had been sinking. The sea now surrounded the pillars, which finally sank nine feet more; thus half their height was above the water, and of that which was beneath the surface eleven feet was embedded and nine exposed to the water; in this space the pillars were perforated by a bivalve, Lithodomus, which is indicated in the figure by the dotted parts. Thus, if we include the lower pavement, the land must have sunk twenty-five feet from the commencement of the Christian era. When the upheaval began we cannot say, but we know it was in progress in 1530, and in 1838 the pavement was again above the sea-level. The downward movement has again commenced at the rate of about one inch annually.

Here, then, we have an evidence of a structure which has undergone an upheaval and subsidence of at least twenty feet, and still stands to attest the quietness and regularity, of the movement.

From the cases cited, seeing the difficulty of proof on account of the peculiar circumstances of position requisite for such proof, we may consider that this motion of the earth's crust is far more general than we suppose, and may fairly be required to account for the successive upheaval and depression necessary for bringing the aqueous rocks to form the surface of continents.

READINGS IN FRENCH.-IX. FEDORA.

SECTION I.

C'ÉTAIT en mil huit cent douze ; Napoléon, à la tête des ses troupes victorieuses dans les plaines de la Moskowa, était entré dans l'antique capitale de l'empire des czars, et de là menaçait la nouvelle ville fondée par Pierre-le-Grand. Poussé par un patriotisme fanatique,3 le gouverneur de Moscou, Rostopchin, prit alors cette résolution qui a porté un coup si funeste au succès de nos armes, celle d'incendier la ville, dont l'empereur Alexandre lui avait confié la garde. Nous ne raconterons pas toutes les circonstances de cet épouvantable drame. Chassés de leurs demeures en feu, croulant sous les efforts des flammes, c'était un spectacle affreux que de voir tous les habitants mêlés à nos soldats, forcés de fuir en emportant ce qu'ils pouvaient dérober à la violence de l'incendie."

La petite fille d'un négociant, à peine âgée de six ans, se trouva perdue dans le tumulte. Abandonnée, transie de froid, elle errait çà et (a) làa à travers les rues que le feu épargnait encore. Son père et sa mère avaient disparu, et personne ne semblait vouloir la recueillir. La nuit se passa ainsi toute entière; et quand le jour commença à poindre, Fœdora, exténuée de fatigue et de faim, s'affaissa devant la porte d'une église1o et se prit (b) à dormir.

Sans doute elle ne se serait plus réveillée," la mort serait venue la surprendre, si une vivandière, qui par hasard vint (c) établir son petit marché de vivres12 près de cette église, ne l'eut aperçue et ne se fut sentie touchée de compassion1s pour la malheureuse enfant. Elle aussi avait des enfants!14 C'est pourquoi elle s'empressa de prodiguer ses soins à la petite orpheline.15 Fodora ne savait comment lui témoigner sa reconnaissance. 16 Elle devint bientôt pour sa seconde mère une aide fort intelligente. Peu à peu, elle apprit (d) à comprendre sa bienfaitrice17 et put (e) lui exprimer tout ce que son cœur renfermait de reconnaissance et d'amour.

this, a pressure on all parts of the containing surface, arising from the elastic pressure of the gas itself. A gas, too, highly-in fact, almost indefinitely-compressible, while, as we have seen, for all practical purposes, a liquid is absolutely incompressible. Now as air is by far the most important of all gases, we shall inquire a little into its properties before considering gases generally. The atmosphere, then, is a layer of air completely surrounding the earth on all sides, and extending upwards to a height usually computed at about forty-five or fifty miles. It fills every space on the earth's surface, and presses, as we shall see, on all bodies with an immense force. We are completely surrounded by it; we live, in fact, at the bottom of an immense ocean of it; and yet, except when it is put in motion, we scarcely notice its presence. Though thus unnoticed, however, it is of the utmost importance to us. Without it all life, animal or vegetable, would droop and die; our fires and lamps would refuse to burn; and when the sun shone, instead of even gradations of light and shade, we should have either almost intolerable brightness or the blackest darkness. No clouds would shade the sun, nor any rain fall to water the earth; all would be a barren, lifeless blank. We see, then, something of the benefits we derive from it, and these surely render it desirable for us to study some of its phenomena. Its chemical properties have already been explained in our lessons on Chemistry; we need, therefore, say little about them. It is not a simple gas, but a mixture consisting almost entirely of oxygen and nitrogen, in the proportion of nearly 21 parts by volume to 79 of the latter. Small quantities of carbonic acid and watery vapours are also present. The former of these is a poisonous gas given off in the breath, and by fires, and burning bodies, and would speedily accumulate, so as to destroy life, had not the Creator mercifully caused that trees should feed upon it, removing the carbon it contains, and building that into their own structures, while they set free again the oxygen which was united with it in the gas. Winds mix the different portions of the air, and thus remove this gas from crowded cities and bring in its place purer air.

The watery vapour in the air varies very greatly in amount, and, as will appear, performs a very important office, being the cause of rain and dew.

Though we notice the presence of the air so little, it is a material substance; that is, it occupies space to the exclusion of other bodies.

A simple experiment will furnish conclusive proof of this. Float a cork on a vessel of water, and invert over it a glass jar. On pressing the jar down, the position of the cork will show that the level of the water inside is below that outside; something, then, must be there to press it down, and that something is the air contained in the jar. If we have a stop-cock inserted in the top of the jar, or use a bottle with the bottom cut off, on opening the mouth the air will rush out, and, the pressure being removed, the water inside will rise to its former level. We see, then, that though the jar would have been stated to be empty, it was in reality full of air. In the same way a bladder or air-cushion may be filled with air, and will sustain pressure almost as if it were solid.

If we take a large sheet of thick cardboard, or an open umbrella, and run, holding it so that the air meets its flat surface, the resistance we shall experience will afford an additional proof that the air which thus opposes the motion is really a material substance.

The experiment we mentioned above-namely, immersing a glass jar in water-though so simple, is an important one, as it illustrates to us the principle of the diving-bell. In laying the foundations of bridges, piers, or other structures rising out of water, it is very desirable, and, in fact, absolutely necessary at times for some person to be down at the place where the work going on. Now if a coffer-dam had to be constructed to keep out the water it would add greatly to the expense of the work, and also to the time occupied, but this can be dispensed with by the use of a diving-bell. This consists merely of a large iron vessel, made strong enough to resist the pressure of the water. It is open at the bottom, and has a ledge round it, on which people may sit. The bell is raised a little above the level of the water, so that the workpeople may enter it, and then it is gradually lowered into the water by means of chains; the air inside keeps out the water, so that those within remain dry. As the bell descends, however, the air becomes compressed, and the water rises a little way. To remedy this, and also to

maintain a supply of pure air, pipes are brought down from some powerful force-pumps, and by means of these the bell is kept full, and supplied with fresh air. Thick glass windows are placed in the top to give light to those within. The condensation of the air by the pressure of the water produces a sense of oppression, and frequently a pain in the eyes or ears: this, however, gradually passes away. The men are sometimes provided with a waterproof dress and helmet, clothed in which they can get out of the bell, and walk about at the bottom, air being conveyed to them by pipes. Frequently, indeed, the bell is dispensed with altogether, and these dresses only used; the air-pipe opening into the helmet, and the excess and waste air escaping by a suitable valve; heavy weights are then fastened to the feet to keep the man at the bottom. Sounds made under water are conducted by it to a considerable distance, and hence by taps on the sides of the bell messages are transmitted to the surface. One of these plans is frequently used for the recovery of property from sunken vessels, and for fixing tackle, so as to endeavour to raise them to the surface, and large amounts of treasure have frequently been thus recovered. The action of the condensingpump, for forcing down the air, will be explained in a future lesson.

Since air is a material substance it has weight, and we must now see how to prove this, and also to ascertain what its weight really is.

To weigh an ordinary substance, we have merely to place it in one scale of a balance, and place our weights in the other. This plan, however, will not answer here, since the air presses on both; we have, therefore, to proceed in a different way. A large glass globe, having an opening which can be closed by a stop-cock, is procured, and by means of an air-pump it is completely emptied of air, and very accurately weighed; the air is then admitted to it, and the difference thus produced in the weight accurately noted. By now filling the globe with water its cubic contents may easily be ascertained, and from this we can calculate the weight of a cubic foot or any other volume of air.

In this way it is found that 100 cubic inches of air weigh, at the ordinary temperature and pressure of the air, a little over 31 grains, and hence a cubic foot weighs about 14 oz. Though this weight appears small, and actually is so, when compared with the weight of solids or liquids, yet if we calculate the weight of air in any building we shall find it much more than we expected. Suppose, for instance, we have a room 20 feet by 15 and 10 feet high, it contains 3,000 cubic feet. The air in it therefore weighs about 3,750 oz., or rather more than 2 cwt. The weight of other gases may be ascertained in a similar way, and by comparing the weights of equal bulks of them with that of air, at the same temperature and pressure, we can ascertain their specific gravities.

In making this experiment an air-pump was required; and as this piece of apparatus is necessary in nearly all pneumatic experiments, it will be as well to explain its construction at once, before passing on to notice the effects produced by the weight of the air.

The simplest instrument for removing the air from any vessel is that known as the exhausting syringe, and is represented in Fig. 1 on the next page. A is the globe from which the air is to be removed; this is furnished with a stop-cock, B, and screws on to the end of the syringe; C D is the cylinder, which is accurately turned inside, and in which the piston E works airtight. In order to prevent leakage past the sides of this, a groove is turned in it, as shown, and cotton or some similar packing is wound tightly round, and then saturated with oil. In this way it is made to fit much more tightly, and the wear is likewise greatly diminished. A pipe, closed by a stop-cock F, opens into the cylinder near its lower end.

Let the piston be at the lower end of the cylinder; the valve F must now be closed and в opened; the piston is then raised to the top, and the air contained in A will expand and fill the cylinder. B is now closed, and F opened, and as the piston descends it will force the air contained in the cylinder through F. The taps are again reversed, and a similar process repeated till nearly all the air is removed.

If the area of the cylinder be just equal to that of the globe, one-half the air in the latter will be removed by the first stroke, and the density of that within will be of what it was; similarly, after the second stroke it will be, after the third, and so on.