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to the law of progression in the density, or rather in the rarity of speaking, however, this acid seldom comes before the notice of the the atmosphere, exhibited in this table, it might be shown that a chemist; moreover its compounds are characterised by their difcubic inch of the air we breathe at the surface of the earth, would, ficult solubility, hence it may be considered as "hors de combat." at the height of 500 miles above it, fill a sphere equal in diameter Applying the facts just deduced, remembering that the grand to the orbit of Saturn; that is, on the supposition that the power combustion-supporting function is strongly developed in chlorate of expansion in the air were not counteracted by intense refrige- of potash-remembering that nitrate of potash (nitre) is a conration, or by the action of gravity on its attenuated particles. gener of the former, and that it is an essential component of gun

For measuring the heights of mountains by the barometer, powder-you will now know, if you did not know before, the reason Laplace has given a formula, which was modified by M. Biot into why gunpowder burns when rammed into a gun from which all the the following:

atmospheric air is excluded: Gunpowder carries within itself

combustibles --charcoal and sulphur, and a supporter of combustion, 1000 log: hi oxygen (in the nitre)-hence it is totally independent of the aid

of atmospheric air. Many gunsmiths are so ignorant of chemistry, in which p denotes the vertical distance, in English feet, between that they are not aware of the true conditions under which gunthe two places whose difference of level is required; n, the height powder burns. You may sometimes see a little hole drilled in the of the barometer at the lower station, and h the height at the side of a gun breech, the use of which, gunmakers will tell you, upper station ; T and t denote the corresponding temperatures of is to let in the air and promote the burning of the powder. This the air on the centigrade thermometer, at the stations respectively; is simply ridiculous. and y, denotes the latitude of the place.

In the first place, the powder does not want air ; in the second M. Oltmans has constructed tables by means of which this place, through this hole no air could enter, seeing that the expanformula can be easily calculated in metres; the only difference sive force of the inflamed gunpowder is outwards. This little being in the factor 60346 feet, which in the original formula is hole facilitates the loading of guns-rifles especially,--and facili. 18393 metres. These tables, with the manner of using them, are tates also the escape of foul air or vapours : beyond this it is of no to be found in the “ Annuaires des Bureau des Longitudes.” service whatever. The student will find a similar formula with an example worked, Seeing that nitre is a congener of chlorate of potash, you may in “Miller's: Hydrostatics.” If the altitude to be determined by perhaps ask whether it might be used instead of the chlorate for the barometer be not very great, one observer alone can perform the purpose of yielding oxygen gas. Yes; it sometimes (unmixed the experiment; but if the altitude be very considerable, and with oxide of manganese) is used for this purpose; but yielding requires a long time between the observations in order to complete up its gas with greater difficulty, it is less efficient. You perhaps the ascent, the pressure of the atmosphere may vary, and it will also ask, whether the chlorate might not be used instead of nitre then be necessary to have two good barometers. One of the as a constituent of gunpowder : Theoretically I might answer observers with one barometer then remains at the foot of the Yes; but practically, No. Gunpowder made with chlorate of potash mountain, while the other observer ascends to the top with the is far too explosive for safety. Not only would there be danger other. At a given hour, cach observes his own barometer, and of explosion from the act of ramming, but the danger attendant on thus the true height of the column at each place, the true differ- the manufacture of such gunpowder on a large scale would be ence of the columns, and consequently the true difference of level frightful. The French tried the manufacture during the wars of between the places are accurately obtained.

the great revolution, and are even said to have used chlorate gunpowder in one of their campaigns; but the frequent explosions which occurred at the powder-mills led to the final abandonment

of the process. LESSONS IN CHEMISTRY.-No. XVII. A very simple, though indirect, method of demonstrating tho

facility with which chlorate of potash evolves its oxygen is as Resuming our consideration of oxygen, I shall require you to follows. Powder two or three grains of the substance separately, arrange the generating apparatus as before; and this being done, and an equal weight of brimstone separately; incorporate these on to fill several eight ounce, or ounce and a half, bottles full of the a piece of paper, by means of a feather or other soft body; wrap gas. We will proceed to use this gas very speedily. I wish, the mixture in a piece of paper, place the envelop on an anvil or however, before doing so, to direct your attention to certain other hard surface, and strike it smartly with a hammer. The properties of chlorate of potash dependent upon the oxygen it whole explodes with a violent report. Occasionally the expericontains.

ment is varied by rubbing a few grains of chlorate of potash and The most prominent characteristic of oxygen, as you are now

an equal quantity of sulphur sharply together in a mortar, by a aware, is its property of supporting combustion; the idea would series of sharp short strokes, or rather downward prishes, half seem likely enough, then, that a substance containing so much stroke, half blow, when a series of explosions results. When peroxygen as does chlorate of potash, and delivering up this oxygen cussion guns

first came into use, this mixture of sulphur and chloso readily, should also be a powerful supporter of combustion rate of potash was employed as the material for charging caps; We shall see.

but the result of its combustion was found to be so destructive to Dissolve some chlorate of potash in water; dip into the solution the lock, that its employment was soon abandoned in favour of a piece of paper (blotting-paper is best); dry the paper, and bring the so-called anti-corrosive caps, in which fulminating mercury it into contact with flame or a red-hot coal. I do not wish the takes the place of chlorate of potash and sulphur. We will now paper itself to burst into flame, but the contrary; if therefore this return to the consideration of gaseous oxygen. should occur, blow out the flame, leaving a mere ignited paper If oxygen gas be so powerful a supporter of wood and other ordiedge. Remark now how curiously the ignition traverses the nary combustibles, the supposition would appear likely, from a paper, which no longer burns as common paper. I dare say you priori reasoning, that bodies incombustible in atmospheric air, or will recognise something like this phenomenon. You will say it imperfectly combustible, should readily burn in this gas. I do burns like touch-paper. Touch-paper indeed it is, of the best qua- not know whether you will be surprised to be informed that iron, lity; far better than you could have made with the ordinary agent and indeed all metals without exception, are combustible. As ----saltpetre; and now you may remember the following important regards iron, you have often, I doubt not, witnessed its combusfact: that any substance capable of making touch-paper must con- tion when heated to whiteness in a smith's forge and rapidly tain an acid which holds fwe atoms of oxygen.Therefore, know-withdrawn, though probably you failed to reason on the bearings ing this rule, it follows that chlorate of potash, if placed before of the phenomenon. We will now show how exceedingly comyou as an unknown substance for examination, would at once have bustible is iron in oxygen gas. There is an old-established been determined as containing one out of four acids.

conventional--a " lecturing" method of performing the combusNitric

tion of iron in oxygen gas, wbich I will describe further on. It Chloric

is well adapted for display in lecture-rooms and generally on the acids Bromic

large scale; but it is not the best adapted to the requirements of

our little bottles. Iodic

I shall modify the experiment as follows. Take a circular disc Straining a point, we might admit a fifth acid, the “perchloric," of tin plate, fig. 1, large enough to cover the mouth of your oxygen containing no less than seven equivalents of oxygen ; practically I bottle, and perforate this pipe centrally with a little hole, just large enough to admit a needle tightly; finally, stick the eye end EXPERIMENT.--For the performance of the succeeding exof the needle in a cork, so that an arrangement may result as fol- periment we shall requiremin addition to the glass jar or bottle, lows nally, dip the extreme point of the needle in melted brim- cork, and metallic disc, already described the following little instrustone, and this part of our arrangement is complete.

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ment, fig. 7, being a small copper ladle, secured by rivetting-not Fig. 1. Fig. 3.

Fig. 7.

soldering—at the point marked I. These instruments are termed Now proceed as follows. Ignite the brimstone at the point of to the action of gases, liquids or fusible solids. We shall require

by chemists deflagrating ladles, and serve the purpose of exposing the needle, and plunge the latter into a bottle containing oxygen two of these ladies; one for the purpose of igniting sulphur, the gas, fig. 2. Theneedle will burn vividly, throwing off sparks in other for the purpose of igniting phosphorus, in oxygen gas. all directions, some of which, in all probability, will stick in the Ignition of Sulphur-Having put a little sulphur into one glass, partially fusing it. I repeat that the mode of operation here described is not the manner already described, ignite the sulphur by heating it in the

of-these deflagrating ladles, attached to a cork and disc in the most elegant, but it is the best adapted to the necessities of our fame of a spirit-lamp. When thoroughly ignited, dip it into a present apparatus. The usual method of performing the experi- jar or bottle containing oxygen. Remark the character of comment is by employing, as the gas receiver, a jar of this kind, bustion--the pale blue lambent flame, the small amount of light, placed to stand in a plate containing water, and covered with a the gaseous nature of the result of combustion. When the sulglass pane, fig. 3; using a helical or corkscrew-formed wire of this phur has ceased to burn, cover the receiver or bottle with a glass kind, fig. 4. If you can procure some of these gas jars, well and pane, and put it aside.

EXPERIMENT. --Combustion of Phosphorus in Oxygen Gas.Fig. 3.

Fig. 4.

I am about to mention certain details connected with the performance of this experiment, and you must attend to them implicitly, otherwise your experiment will fail, and yourself, 'most likely, will be severely burned. Pour a lump of phosphorus from the water in which you will purchase it, into a plate of water; cut off a very little lump (not bigger than a pepper-corn) under water; remove the piece thus cut off, not with the finger and thumb, but a pair of tweezers, scissors, or something of that sort; dry it by contact with blotting paper ; put it into a deflagrating ladle; ignite it by contact of a hot wire applied to its surface, not by a flame applied underneath the ladle ; plunge it into a bottle or a jar

i containing oxygen, and remark every peculiarity of the combustion which ensues. Preserve the results of this combustion, as you have preserved the others. The examination of all these pro

ducts shall be the subject of our next lesson. good, you may employ them in performing the experiments about to be detailed; if not, you must be content to use large-mouthed bottles.

LESSONS IN GEOLOGY.-No. XLIX. EXPERIMENT.-Bore a hole through a piece of charcoal ; pass through the hole a wire; bend the wire into a sors of knot By Thos. W. JENKYN, D.D., F.R.G.S., F.G.S., &c. underneath, and attach it above to a tin-plate disc and cork, as

CHAPTER V. represented in fig. 5. Ignite the charcoal ; plunge it into the jar or bottle, fig. 6; wait until the combustion has ceased ; then secure the

ON THE CLASSIFICATION OF ROCKS. mouth of the jar or bottle with a glass pane. The charcoal will

SECTION III.
Fig. 5.
Fig. 6.

ROCKS OF RECENT FORMATION,
The rocks which contain fossils, and which on that account are
distinguished by the name of fossiliferous rocks, have been
divided by geologists, generally, into three series. The lowest
contain the most ancient forms of animal existence, and
are therefore called palæozoic (from walatos, palaios, old,
and {wn, zoé, life), that is, old-life rocks. The series rest-
ing upon the palæozoic are called secondary rocks, or
mesozoic (from uscos, mesos, middle, and twn, zoé, life),
that is, middle-life rocks. The series resting on the mesozoic
are called the tertiaries, so called because their beds contain a
third form of organic life. In the lowest and in the middle series,
all the imbedded fossils are remains of animals altogether extinct.
In the third series, or the tertiaries, the lowest group of rocks

contains some extinct species and a few of existing species; a burn with extraordinary splendour, and the sole result of com- higher group contains less extinct species and more of the present bustion will hereafter be found to be a gas, invisible like oxygen, race; and in the highest group, there are extremely few of the but totally dissimilar to it in every other characteristic. ancient species, and a vast majority of the species which now live,

On these accounts, the tertiary series, according to the comparative 1. Peat Bogs. Peat mosses are well known in all the mounamounts of extinct and existing fossils which they contain, have tainous districts of the north of Europe and America. They are been called Eocene, Meiocene, and Pleiocene; terms which will divided into two distinct classes : first, immersed formations probe explained 'in our next lesson. All the tertiary beds contain duced by the accumulation of aquutic plants, such as reeds, sedges, fossils of the present race of animals; but the group called the &c.; and secondly, the emerged formations, caused principally by Newer Pleiocene by some, and Pleistocene by others, contains so the growth and decay of the plant called sphagnum. Some much as 95 per cent. of the present species, and is therefore called peat mogges lie frequently in highly inclined planes. Near Kiel, in a rock of MODERN formation..

Northern Germany, vast beds of peat show the two formations But, in the order of superposition, there are series of rocks much superimposed, where the peat has first grown in a basin or hollow higher and newer in geological sequence than the Pleistocene several feet deep, and when it has reached the surface of the beds; rocks which are characterised by having all their fossil water, the emerged formation has commenced. A third mode of shells identical with the species that are now living. It is this peat growth has been observed in the Vosges, and in Denmark, fact that distinguishes the lowest of these beds from the newer where, in deep, but small basins, the peat-forming plants have pleiocene, or rather the pleistocene, whose deposits always contain begun to grow at the surface of the water, and the basin has sime proportion of an extinct species. It has hitherto been found become gradually filled by the immersion of the floating turf, and difficult to coin a term or a phrase that shall properly and fully this continually thickened by the growth of new plants. express the geological characteristics of these later groups of You may easily think that such abysses, concealed by verdure, rocks. Some have called them Post Tertiary, others Post Pleiocene, have often proved dangerous to travellers and to cattle. These and some continental geologists have tried to introduce the name basins are filled with numerous bones and instruments of various Quaternary, or the fourth series, a term which seems as admis-kinds, both ancient and modern, which give a clue to the different sible as the word tertiary for the underlying-rocks; and in some epochs in their formation. works they are called RECENT formations

2. DELTAS OF RIVERS. The streams and brooks which issue It will answer all the purposes of this lesson, if we agree to from mountain sides are all charged with earthy particles, which designate all the beds 'which contain the fossil remains of the they deposit in the beds of rivers as mud, gravel, and pebbles, and existing races of plants and animals, by the term POST PLEISTO- thus gradually form alluvial plains. If the force of streams be CENE rocks. This class of modern 'rocks comprehend not only strong, the current transports an immense quantity of detritus to those strata which can be proved to have originated since the the mouths of rivers, where they form the accumulations of silt creation of man, but also sedimentary beds of much greater and sand, called deltas. "In these deltas are imbedded the leaves extent and thickness, which contain no signs of man or his works, of plants, branches of trees, remains of animals, shells of fish, but encloge remains of species of animals identical with races human bones, and works of art. Specimens of such formations now living. It is true that in some of the lower beds of even are supplied by some of our rivers in England, especially the these modern rocks we find the bones of ancient quadrupeds, such Mersey, the Dee, the Severn, and the Thames; but they are preas the mammoth, the mastodon, the megatherium, &c., species sented on a large scale by such rivers as the Nile of Egypt, the that probably never co-existed with the human race; nevertheless Ganges in India, and the Mississipi in North America. the shells that are found fossil in these beds are the same as those To constitute a series of deposits a post pleistocene group, of testacea now living.

it is not necessary that they should always be found superim

posed upon the Tertiaries, for sometimes they may be found POST PLEISTOCENE SERIES.

resting on the most ancient rocks. In the annexed diagram, Submarine Deposits.

a a represents rocks of the greatest antiquity, and d the ante

historical deposits ; c, the rocks formed since the creation of Deltag of Rivers. 1. The present period Coral Reefs.

man, and b rocks that are now in the process of formation. Deposits in Lakes.--Salt. Rocks now forming. Peat Mosses. Beds of Lava, and Volcanic Cones.

b Sand Dunes,

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or

Raised Beaches. 2. The historical

d Shell Marl. period, or Rocks formed since Submerged Forests.

Fig. 1. Recent Deposits Resting upon Ancient Rocks. the creation of man.

Deposits in Caverns.
Beds of human remains.

3. SUBMARINE Deposits. You have already seen in the lessons 3. The ante-bistorical Loess of the Rhine.

on the agency of running water, that rivers which deposit their period, or Rocks formed since Regur or bottom soil of India.

gravel and sand in deltas, carry their finest particles far into the The Till.

bosom of the sea, where, after having been transported by currents the creation of the

The Newer part of the Boulder forma. and agitated by the waves, they finally settle down as a sediment present races of tion with Erratics.

on the deep and quiet floor of the ocean. Colonel Sabine, in his plants and animals.

calculations on the sediments carried down by the river Amazon N. B. In the rocks of this ante-historical period, all the fossil in South America, has shown that strata are now forming in

shells are of the species now living ; they are destitute of regular deposits over great spaces of the bed of the ocean. The human remains; and the bones of quadrupeds imbedded in system of DREDGING carried on by scientific men, uniformly shows them are partly of extinct species.

that the strata which are now deposited in the bed of the sea, are post pleistocene rocks, either by name or by arrangement, in any are comparatively quiet. It is right to say that you will not find this distribution of the pebbly where the waters are much agitated, sandy where the

agitation is moderate, and argillaceous or clayey where the waters work on Geology; and that it is made solely to facilitate your progress in the knowledge of this particular formation. This it is well known that there are many beds now in the course of

Besides these rocks deposited mechanically in the sea by rivers, series is divided into three groups of rocks, viz. rocks that are formation by the chemical agency of the calcareous, siliceous and now in the process of formation ; rocks that have been formed ferruginous matter which is swept by rivers into the ocean.

At since the existence of man; and rocks that have been deposited the mouth of the Rhone in the South of France, calcareous beds since the creation of the present race of plants and animals.

are now forming in the Mediterranean. On the shores of the Red I. ROCKS NOW IN THE COURSE OF FORMATION.

Sea a rock formation is now in progress, composed of sand, gravel,

corallines, fragments of older rocks, weed, pottery, and bits of Your attention has been already directed to the rocks that are wood washed up by the sea and cemented together by carbonate now in the process of formation, in the lessons which have been of lime slightly coloured by oxide of iron. given on the reproductive agency of fire, water, and wind, as 4. THE GROWTH OF CORAL Rocks. The best modern instance agents of change in the crust of the earth. You are therefore of the formation of coral rocks is found in the Bermudas, and the prepared for the statement that rocks are being formed in our own Bahamas. The coral reef in these districts consists of masses day.

of numerous species of madrepores, astræa, and several others, growing confusedly together, without any other apparent British Museum an indisputable specimen of a human skeleton, order than that of accidental succession and aggregation both found imbedded in a rock of solid limestone formed on the shores upwards and sidewards. In the cavities of the mass are found of Guadaloupe. This rock can be proved not to belong to tho fragments of corals, shells and other organic remains, perfect or class of ancient limestones, but to be a very recent alluvial formaþroken, sand and chalky mud, and the whole becomes solidified tion; for it contains, besides shells of the present sea, fossil into a compact rock by the aid of calcareous cement, while the arrows, stone hatchets, and pieces of rude pottery. A battle upward growth of the living coral, and the accumulation of loose between the Caribs and the Gallibis took place on that spot in material on the surface proceed at the same time together. The 1710, and there is every probability that this is a skeleton of one coral work is ever in progress until it reaches the surface of the of the slain, either buried there, or sunken and imbedded when water. The loose materials are either dispersed through the the coralline mass was soft. crevices and inside of the reef, which thus pack and cement it The circumstance that has occasioned the greatest perplexity to together, or else they are carried landward or seaward to form the geologists is, that some signs of human contrivances, and even compact bases of other formations.

human bones, have been found in caverns, mingled with the bones 5. Salt FORMATIONS. Very little is known of the origin of of animals that are certainly extinct as to those districts, if not rock salt, and geologists have not been able to decide whether the absolutely extinct as to the globe at large. As far, therefore, as precipitation of salt is owing to evaporation, or not. It seems

mere geological evidence is concerned, it would be unsafe to say clear that, in the basins of lagoons, lakes, or inland seas, pure that man has not been az inhabitant of the earth for a much salt can be formed only in the central parts of such basins, parts longer time than modern chronologists assert. As to the human where no earthy sediment could be brought by currents, and bones which have been found mixed with those of extinct animals where no sand could be drifted by winds. We cannot say what in certain caverns of Belgium and France, all of which seem to chemical processes are now going on in the quiet depths of the have been deposited at the same time during the formation of the Mediterranean, the Red Sea, and the Dead Sea; but the Runn of most recent tertiary strata, Dr. Buckland has shown that the Cutch in the delta of the Indus, and some of the lakes in the human remains must have been introduced subsequently. districts of Mount Ararat, explain to us how beds of salt are

That some rocks have been formed since the creation of man, is formed in the present day. Professor ABICH, in his notice of evident from the fact that they contain the remains of human “the Natron Lakes in the plain of the Araxes,” says that in one beings, implements of human art, and several vestiges and traces lake, at the north-west foot of the Greater Ararat, the water, in of the operations of man. In basins or hollows covered with peat the warmest season, retires three or four feet from its usual banks, mosses, and in districts known as submerged forests, human bones on which a crust of salt a few feet broad and about half an inch and works of art are imbedded in company with the remains of thick is found deposited, of generally a pale rose-red colour. recent animals. On the west shore of the Red Sea a rock has Other lakes lying to the south-east of Little Ararat, are of the been formed composed of sande, gravel, corallines, pottery, and same description. One of them is remarkable for having a broad weeds, cemented by carbonate of lime, being in thickness from zone of white clayey soil covered with luxuriant reeds and an inch to three or four feet, and sometimes alternating with grasses. This soil forms the margin of the lake all round, and is thin and loose layers of shingle. This rock stands at five or six 80 soft that the feet sink in it. It is covered with an accumula- feet above the high-water level, overlying the raised coral beach, tion of irregular lump-like incrustations of a very

compact salt, of and inclosing bones of camels and fish which to this day contain a white colour and inclining to red, and with a foliated structure. animal matter. On the shores of Sicily, Greece, Asia Minor and These saline crusts lie all around the white shore, chiefly floating Aden, similar marine calcareous rocks have been formed. At in the water of the lake ; and some fragments that were broken Rhodes, at the height of six feet above high-water mark, a caloff floated about, like shoals of ice, on the deep-red surface of the careous conglomerate is observed that contains fragments of water, which had all the appearance of water just on the point of ancient pottery, recent shells, and pebbles of limestone, gneiss, freezing. On examining the floor of the lake, as far as could be basalt, serpentine and porphyry. In several places on the caldone by tying several Cossack spears together, it was found careous cliffs that skirt the Mediterranean between Alexandria covered with a similar saline crust in unbroken continuity, and and Aboukir, there is a bed, about a foot thick, consisting of appeared to increase in depth, from the shore, in such a manner as bleached human bones, derived from the ancient Roman and Greek to leave no doubt that a layer of salt, several inches thick, extends cemeteries, intermingled with those of the slain in battle in the over the whole bed of the lake.

neighbourhood. These bones are covered with a layer of sand Our space will not allow us to consider other rocks that are now and gravel, varying in thickness from a few inches to three or four forming as sheets of lava, as volcanic cones, and as sand dunes.

feet. They appear to have been washed into their present posi.

tion by the drainage water running from the higher grounds to II. ROCKS PORMED SINCE THE CREATION OF MAN.

the sea. What is remarkable in these bones is, that though they

are in an excellent state of preservation, they are not fossilised. Every honest geologist acknowledges that he is not able to mark the point of union between historical and geological time, and that he cannot define where geological epochs terminate, and the historical era begins; that is, that he cannot tell, from the contents of rocks, at what time man appeared on the earth. If we might be allowed to argue in the old Aristotelian method, we might infer that, where we find in existence a large number of animals that seem to contribute to the use of man, we have also some evidence of the existence of man: for, if the bones of the ox, the horse, the dog, the deer, &c., the bones of animals which are characteristic of the present creation, are found in the sediments of ancient lakes or the alluvium of ancient floods, there is nothing to prevent the indirect inference that the race of man had commenced when such beds were deposited.

When the attention of men was first directed to organic remains found in rocks, many fossil bones were mistaken for the bones of man. In 1577, Professor PLATER, of Basle, found near Lucerne, the bones of a man, which he made out to be a giant nineteen feet high. These turned out to be the bones of an elephant. SCHEUCHZER published an account of a fossil skeleton, under the title of “ Homo Diluvii Testis," or man a witness of the deluge. Cuvier afterwards proved that this was the skeleton of a gigantic Fig. 2. The present Cone of Vesuvius, eith Somma to the left, salamander or protens. SPALLANZANI gave an account of a hill

and Naples in the foreground. in the Island of Cerigo, that consisted of fossil human bones; but BLUMENBACH showed satisfactorily that all of them belonged to Geologists can satisfactorily prove that a vast portion of the quadrupede. Sir Alexander Cochrane brought and placed in the lavas, the tufas, and the trap dgkes of Etna, of Vesuvius, and of

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a

the Island of Ischia in the Bay of Naples, has been produced 1. THE LOESS OF THB RUNE, This Loess is sometimes called since the historical period. The Post Pleistocene formations about Lehm, and consists of a deposit of yellowish marl, often not less Naples show that very great changes have taken place through-than fifty feet thick, abounding with calcareous concretions and out the whole of the volcanic district of Campania during the last sandy nodules. It is this kind of rock that forms groups of low two thousand years. One of the most remarkable is the formation hills at the foot of each mountain chain that enters the river valley. of the modern cone of Vesuvius since a D. 79, which is represented It is sometimes as high as 1,500 feet above the level of the sea, in fig. 2. Before the year just mentioned, Mount Vesuvius showing that the bed of the Rhine was once at that elevation. might have been regarded as an extinct volcano, but at that It forms also the subsoil of the plains on which Coblentz and period the rocks of the mountain were blown to pieces and fell Bonn are situated, and extends up as far as the falls of Schaffhauinto the gulf beneath, and its cliffs form the circular ridge, called sen, where it is seen to repose on beds of rolled flints and other Somma, which is several miles in diameter, the highest point of pebbles of the drift period. It contains land shells and freshwhich appears to the left of the engraving. The enormous cone in water shells of many existing species; but the only mammalian the centre has been formed since the year A.D. 79.

remains found in it, are a few bones of the horse and the mamIn the Bay of Baiæ, not far from Naples, there is an entire moth. mountain, consisting of pumice and ashes, a mile and a half in 2. The REGUR OF INDIA. The Regur is the cotton soil which circumference, and 450 feet high, which was formed by an earth- covers one-third of all southern India, ranges northward to a quake on Sept. 29, 1538. During this catastrophe the north coast great distance, and extends into the Burman empire. Its colour of this bay was permanently elevated twenty feet, exhibiting is bluish black, greenish or dark gray. Its thickness varies from tufaceous strata filled with articles fabricated by man, such as three to twenty feet. fragments of sculpture and pieces of pottery, which are every found under the vegetable mould that covers the surface of the

3. THE TILL. In almost every district of the globe there is where mingled with marine shells.

Examples of raised beaches, of shell marl, and of submerged earth, a deposit of sand, mud and loose gravel, which has been forests, are found in almost every part of the world, and they, in called alluvium, from alluo to wash, and alluvio, an inundation. It the majority of instances, afford proofs that they have been is called by this name, because the bed of gravel has every appear. occasioned by physical changes of very modern date.

ance of having been spread by a flood, and the grains of sand and These Post Pleistocene groups of rocks claim the particular atten- pebble appear as if they had been rolled by water, and had formed tion of young geologists, as they furnish us with the clearest the bed of a mighty river. instances of the harmony between Geology and Revelation ; for

It is found in the higher latitudes of North America and of these rocks establish the fact stated by Revelation, that man is Europe, where it extends from Finland and the Scandinavian among the latest of the animals created to inhabit this earth. mountains to the North of Russia, and the low countries bordering They show also that the epoch when the existing races of plants on the Baltic, and on the eastern coast of Scotland and England. and animals were placed on the earth, must have been recent. This deposit consists of sand, mud and clay, sometimes in a stratiSuppose that human remains, say bones or implements, had been fied state, but very often wholly unstratified, having a depth of found in ancient rocks which can be proved to have been formed more than a hundred feet. It is the unstratified part of this at the bottom of deep oceans, or that they were found mingled formation that is called by geologists “the Till.” It contains with the earliest organic fossils in the Silurian rocks, it would numerous fragments of rocks, some angular, some rounded, have been impossible, for geologists, at least, to reconcile the derived from formations of all ages. Some of the blocks are of two records of the Almighty Creator. Instead of this, geology immense size. This rock is almost everywhere destitute of proves, in harmony with Scripture, that the introduction of man organic remains, except where they have been washed into it among the creations of earth has not been of very remote anti- from older formations. quity.

4. The BOULDER FORMATION. When this formation contains

large blocks of ancient rocks it is called “the drift," and "the III. ROCKS

boulder formation," whose probable connexion with floating ice has already been considered. Wherever it has been examined

in Russia, it has been found throughout to be superimposed upon It has been intimated already that it is next to impossible to strata that contain recent shells, and that, consequently, the mark the limits between chronological time and geological accumulation is post pleistocene.

The same is the case about epochs. You have seen that some

beds in this Post Upsala in Sweden. Everywhere it shows that the transport of Pleistocene group give indubitable proof that they were erratic boulders continued to take place after the North of Europe formed after the creation of man. Still, there are other beds, lying had assumed its present physical features. lower in this group, that present satisfactory evidence that they were deposited before man came upon the earth. First, no fossils of human bones, and no relics of human art, have ever been found in them. Secondly, in none of these rocks, formed as alluvial

LESSONS IN ITALIAN GRAMMAR.—No. XVII. beds in the waters of the ocean, have any human remains of any

By CHARLES TAUSENAU, M.D., kind been discovered. Thirdly, nevertheless the remains of of the University of Pavia, and Professor of the German and Italian animals and of plants, identical or very similar to the existing races,

Languages at the Kensington Proprietary Grammar School. are found in the lower formations of the group. Fourthly, a comparison of these beds with the physical conditions of the globe

EXERCISES. -ITALIAN-ENGLISH. at the beginning of the Pleiocene period, shows that the state and Ha man-dá-to la lêt-te-ra a Gio-van-ni. Ti-ra-re ad un ucaspect of the earth were very similar to the present, and that this cêl-lo. Il mer-cán-te pên-sa al gua-da-gno. Tóc-ca un fiosimilarity continued to increase till we approach the historical ri-no ad ú-no. O-gnú-no tí-ra l' a-cqua al sú-o mo-lí-no.

Dál-le pa-rô-le si vên-ne ál-le ba-sto-na-te. A chi l' a-vé-te The districts of Italy, to which your attention has been already mo-strá-to ? a Piê-tro o al-la cu-gi-na! A che pen-sá-te? directed, abound in proofs and illustrations of this statement. pên-80 all' av-ve-ní-re. Ar-ri-ve-ré-mo prê-sto ál-la prôs-siIn the Bay of Baiæ there are, besides the beds of tufa just men- ma pô-sta? E'-gli è cór-80 sú-bi-to ál-la pôr-ta. Par-la-va tioned, other tufaceous beds of a date evidently anterior to the ad u-no stra-niê-ro. Lo in-ci-tò ál-la côl-le-ra. Pre-fe-ri-sce origin of man. These rocks are so thick as to form bills of from il bê-ne al ma-le. La sú-a con-ver-sa-zió-ne mi viê-ne a nô-ja. 500 to 2,000 feet high. These beds contain all the marine shells E'-gli se lo re-ca a dis-o-no-re. La li-be-ra-li-là gli viên imnow abounding in the neighbouring sea, and yet they are inter- pu-ta-ta a di-fêt-to. E's-si ê-ra-no ál-la các-cia, ál-le nôz-ze, stratified with different sheets of lava. In the same manner, à prán-zo, a cé-na, al fe-stí-no. An-dré-te do-má-ni al ri-dótsimilar beds, consisting of clay and volcanic tufa, rise, in the to al con-cêr-to '-c an-drò do-má-ni a un bál-lo. An-dáneighbourhood of Naples, to the height of 1,500 feet above the sea; te a im-pe-ra-re, a scrí-ve-re, a dor-mi-re, a man-giá-re. E'sbut these differ much from the kindred strata at Puzzuoli, for they si ván-no a spás-so, & pas-seg-gia-re. An-diá-mo al caf-se. contain no relic or trace whatever of the existence of man. Per dó-ve si va ál-la pô-sta? ál-la do-ga-na? E-gli è a Ber

In this lower division of the Post Pleistocene group are classed li-no. Sog-giór-na in Fi.rên-ze. E-gli mo-rì in Kot-tin-gathe Loess of the Rhine, the Cotton soil of India, the full of Eng.mo. E-gii lo con-dur-rà a Cê-stria. El-la giún-se a Lió-ne. land and Scotland, and the newer part of the Northern Drift. E-gli è ar-ri-vá-to in Bri-stôl. E'-gli è na-to in Pli-mút-te.

TUE PRESBNT

FORMED SINCE THE CREATION OF
RACE OF PLANTS AND ANIMALS.

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