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LESSONS IN ALGEBRA.
XXI. Le Girondin et le Cent-Suisse; Sections I., II.,
III.; Une Promenade de Fénélon ; Sections
I., II., III., with exercises, etc.............
Sections I., II., with exercises, etc.
XIX, Centenary of Problems
LESSONS IN GEOGRAPHY.
LESSONS IN GEOMETRY.
XXIX. The Augments
XXXIII. Contracted Veibs, which, contrary to the Rule,
XXXVII. Formation of the Tenses of Liquid Verbs 261
XL. Strengthened Stems-continued
XXII. Use of the Prepositions ; Sopra; Sovra ; Su..
XXXII. Exercises and Vocabulary
V. The Dash; Hyphen; Ellipsis ....
Smoothness of the Voice ; Versatility ......
XI. Exercises on Inflections
lation; Promiscuous Exercises : Antiquity
of Freedom; Pope and Dryden......
sal Decay: Eternity of God
can Eagle; Memory; Old Ironsides...
ness; Ode ou Art; God; Niagara
ing; Child of the Tomb; Love and Fame
Character; Success of the Gospel; Power of
the Soul; Hymn of Nature..
dor; Scene at the Dedication of an Heathen
and Jefferson; Posthumous Influence of the
Nature and use of
Table of Loga-
XXVIII. Vibration of the air in Sonorous Pipes
The Irish Tongue
LESSONS IN GEOLOGY.-No. LI.
By Thos. W. JENKYN, D.D., F.R.G.S., F.G.S., &c.
which took place during the tertiary epoch will explain the
inclination or dip which mark the strata in some localities. THE CLASSIFICATION OF ROCKS.
The scooping or denuding action of the ocean upon the chalk SECTION IV.
beds will explain the hollows or the basins in which the ter
tiary formations rest.
In the basins scooped by denudation in the chalk, and which II. ON THE FOSSIL REMAINS OF THE TERTIARIES. are now called the Basins of London, Hampshire, the Isle of
Wight, and Paris, the Eocene beds always consist of a coarse All the beds of the tertiary rocks have every appearance of pebbly gravel, at first spread pretty uniformly over the whole having been deposited in a shallow sea, not far from coast | tract; but afterwards, when the and became more elevated, lines, with much regularity, and in the course of many ages, and consequently the rising rocks yielding different kinds of The earlier beds are very extensive, and consist of rolled detritus, its character altered. If you imagine cliffs of rocks pebbles produced by the rubbing and wearing down of the of different characters, thus gradually rising, and being conchalk Aints, and perhaps of fragments of hornblende and stantly acted upon by the waves of the sea or by running primitive rocks, scattered over a shallow sea-bottom. It is otherwise impossble to account for the immense beds of sand great diversity, you will come by the facts which will enable
water, and this water-action taking place in circumstances of found in the tertiaries.
you to account for the coarse limestones of Paris, the plastic To enable you to derive intellectual advantage from this clay of London, the marly clays of Brussels, the silicious or lesson on the plants and animals of the tertiaries, your mind Ainty formations from the warm springs in Auvergne in Central must keep firm hold of the following principles : 1. The term “ tertiary" implies a secondary” system of France, and for the various limestones of the Greek Islands.
That the vegetation of the first tertiary land, or the Eocene, rocks as already in existence. The highest and newest of
was very luxuriant, is proved by the fragments of wood and these is the chalk,
the fruits of trees which are found fossil in rich abundance in 2. The secondary” beds may have formed either the the Isle of Sheppey at the mouth of the Thames. These fossil bottoms of seas, cr islands and mainlands, for many ages before woods are very great in number and very rich in variety. the tertiaries began to be deposited.
Even in the Isle of Sheppey alone, several hundred species have 3. During this interval, all the districts that now form the been discovered, all of them differing much from existing great plains of Europe were covered by the sea.
plants, though they are closely allied to some which are now 4. Most of the European land of that epoch lay chiefly from found growing in warm climates. There is a large prepon, east to west, and extended far into the Atlantic, connecting derance of a species allied to the palms, something like a kind the land now called England and Ireland not only with Spain, between the cocoa-nut and the screw pine or Pandanus, which but also with the islands to the west of Africa.
are so well known in tropical climates. There are others of 5. At that time the Pyrenees, the Alps, Apennines, the the Nipæ family, which now luxuriate in Japan, and in the Grecian Mountains, the Caucasus, the Carpathians, etc., formed
Spice Islands. a chain of islands in the open sea.
The fossil wood of these trees is often found to have been 6. Things continued long in this tranquil state until a vol, pierced, and almost destroyed, by an extinct kind of Teredo, canic power threw up the Wealden of Kent and Sussex, and before it had been deposited in the mud. Sometimes the a gradual upheaval of the land took place, and the aforesaid wood presents nothing but cavities, which had been left by these islands rose gradually higher and higher above the ocean, and animals, and which were afterwards tilled up with carbonate of consequently more land was formed.
lime. 7. As those vast islands rose, the sea would dash against their sides, dislodye fragments from their cliffs, which they would roll smooth, wear down, until they constituted the The tertiary beds abound in shell animals, both univalve, beds of gravel which now cover the chalk in some places. having but one shell like the snail ; or bivalve, having two
2. The shores of these islands and mainlands were low and shells like the oyster or cockle. The bed called the London swanny, and large rivers brought down the mud and sand to clay is full of.the remains of crabs and lobsters, some of which form Wrat is now the south-east of England, and also the for- are very perfect. One of the most remarkable groups amid mations aonut Brussels.
these tertiaries, is a species of foraminiferous shell, called 9. The seos were tenanted by animals like the shark, and the nummulite on account of its resemblance to a small piece by fishes of the tribes now found in warm latitudes, and by of money. The fossil remains of this shell-fish are so incredibly large shell-fish taut could live either in salt, or in brackish, abundant in some localities, as that rocks of enormous size are water.
entirely made up of them. The tertiary shells bear, for the 10. The rivers were pepled with crocodiles, turtles, tortoises, most part, a considerable analogy to those which exist at something akin to those nu existing.
present, as will be seen in Fig. 1. 11. The sides of the hills and the plains were clothed with Our engraving is only intended to represent a few specimens a rich tropical vege:ation, abomding with the palm-tree and of the tertiary shells, to show their usual appearance and the cocoa-nut. This luxuriant vegetation indicates an abund. character. The entire species, as already determined by naturalance of animal life.
ists, amount to nearly three thousand. Some of the tertiary These geological facts, and others akin to them, will help strata are almost entirely composed of shelly remains in a you to understand some of the peculiar circumstances in which broken and crushed state, and many sandy seams in the clayey you occasionally find the tertiary deposits. The upheavals | beds consist of shell dust. In some places the shells are preVOL, Y.
served in their perfect forms. Some of them are the sheils of the serpent. The crocodiles resemble those which now exist animals that lived in the sea. As the Cypræa inilata or the 1 in Borneo. The tortoises are both marine and fresh-water, but Cowry, 20—the Fusus, 26-—the Cerithium Lamellosum, 14– the marine ones are fewer in number than the others, and they the Pleurotoma, 17—the Lucina, 3—the Ampullaria, 22-the are smaller in size than those now existing. The serpents are Venericardia, 1- the Mitra, 19—the Rostellaria, 23. In of the tribe now represented by the Boa Constrictor and the the Red Crag of Suffolk, a peculiar kind of Fusus, called Python, such as are now found only in tropical climates, and Pusus contrarius, is found, having the whorl and the mouth feeding on birds and quadrupeds. Some of them were of large in a con rary direction. Others are fresh-water shells; such dimensions and measuring in length from ten to twenty feet. as the Cyclostoma, 6—lle Planorbis, 10–the Helyx, 12-the All the tertiary reptiles approach the modern type, and all Cyrena i uniforinis, 1.
the present orders have their representatives in these deposits.
It is remarkable that tertiary fishes of the same species are beds, several species have been found in the Paris basin, espe
Although the remains of birds are very rare in the Eocene found in the most distant localities ; such as the London clay cially those resembling the pelican, the sea lark, the owl, the cf England, Monte Bolca in Italy, and in Lebanon in Asia, woodcock, and the buzzard. There have been some few and These fossil fishes resemble much those which are now found in the Indian Seas and in the Southern Ocean.
rare instances in which the fossil skeletons of birds have been The forms and shapes of some of these fossil fishes are
well preserved. :cmarkably unique. One genus h as, behind its head, a fin Cuvier. In some specimens he discovered even some fossil
The first who discovered the fossil remains of birds was That rises like a tall mast much higher than the length of the indications of feathers. In the lacustrine limestone of Auvergne
ole body: From this mast of a fin, to the tail of the tish, in Central France, also the eggs of an aquatic species are found there extends a corresponding sail, by the aid of which it was
fossil. able to navigate its course in the icrtiary seas. Another fish
QUADRUPED3. is so curiously formed that the height of its body and its fins is three times as much as the length of the animal.
The land quadrupeds of the more ancient tertiaries are The various groups of tertiary fishes comprise many hundred found fossil in much greater abundance in the gypsum beds of species belonging to all the existing orders and families, of Paris than in the formations about London.
There they which nearly two hundred have been figured and described include a great number of species chiefly of the group callai by Agassiz (pron. ággasee); of these forty or fifty belong to the Pachydermata, or the thick-skinned, represented now by the family of the sharks, whose teeth are found in great abundance elephant, rhinoceros, etc.: but the most predominating sre the in the tertiaries.
carnivorous or flesh-eating quadrupeds, such as the wolf, fox, The ichthyological or " fishy" history of the tertiaries may opossum, etc. In England also have been found a few fossil be thus sumined up. In the focene tertiaries one-third of the fragments of the teeth of creatures like the bat--and, what is fish belong to extinct genera. In the newer tertiuries, such most singular, of a monkey, as if, on Lord Moiboddo's princias the Crag, the races are of the genera common to tropical ples, approaches were made towards the production of man! seas, and, throughout, the fossil fishes approach in their all the fossil quadrupeds indicate a mach warmer climate in character to the living races, but all the species are extinct.
their localities than are found now. The name of this group is derived from Taxus, pachys, thick, and depua, derma, plural dermata, skins or hides.
Among the Pachyderms were creatures allied to the horse, The tertiary reptiles are of three classes –some inhabiting of which the tapir of South America seems now to be the best the land, othera rivers, and others the brackish waters of living representative. Another of the tapir group was an ani. cstuaries; but they are all of a kind that prove the climate to mal called the Lophiilor, of which only very imperfect fraghave been of warm temperature. Among these, lizards and sevements have been found in a fossil state, but even those fragments ral kinds of crocodiles abound—so do also turtles and tortoises. point to the existence of more than twelve species. Its name But the most remarkable fact of this epoch is the existence of is derived from lopos, lophos, crest, and óewv, odón, tooth, i.e.
the crested-tooth. All these are supposed to have inhabited timid animal. In external character it was the small deer of the dryer districts of the Eocene land. To the same group the Eocene. belong the better known fossil quadrupeds, the Palæotherium, These quadrupeds are represented in figs. 1, 2, 3, and 4 and the Anoplotherium.
In the Meiocene and Pleiocene tertiaries we meet with the The PALÆOTHERIUM was much like the living tapir in the deinotherium, the mastodon, the elephant, etc. form of the head, having a short proboscis or trunk; but its The DEINOTHERIUM, from ostvos, deinos, terrible, and Onprov, molar teeth resembled those of the rhinoceros. It was about therion, a wild beast, was remarkable in size, in relation both three or four feet high. Unlike the tapir, it had only three toes to the anoplotherians of the older beds on the one hand, and to each foot, and it was also very slender. An animal between to the elephantine groups of inore recent periods on the other. the tapir and the horse would probably be a good representa. The fossil remains of the Deinotherium are nowhere more tive of the Palæotherium, though its species varied greatly. common than in the valley of the Rhine, between Basle and It is supposed to have inhabited districts near water. The Mayence, and they are also frequent in the valleys of the Jura. name is derived from malalos, palaios, old, and Onprov, thé- This animal was of a huge barrel-shaped body, and was twenty rion, a wild beast.
feet long, and in character was something like the hippopotaThe ANOPLOTHERIUM was less clumsy and more agile than the mus. Its body was but little raised above the ground, though Palæotherium, and was a nearer approach to the ruminant group its legs were ten feet high. It lived in water, but its head was of animals. The Anoplotheria were abundant in the older ter- kept entirely out of the water. Its head resembled that of the riaries. The name is derived from a, (av before vowels,) priva- elephant, having a powerful proboscis, and also a pair of large tive, or without, óney, oplon, armour, and Onprov, therion, wild and long tusks curving downwards like those of the walrus.
beast: that is the unarmed animal. Two species have been What is most remarkable in these tusks is, that they are fixed • determined.
in the lower jaw of the animal, to enable it to dig for encculent
Fig. 2. Quadrupeds of the Tertiary Period. 1. Anoplotherium gracile. 2. Anoplotherium commune. 3. Palæotherium magnum. 4. Palæotherium minus. The first species was about as tall as a dwarf ass, but its food. It was the most gigantic of the herbivorous or grass. body was much longer, with the appendage of an enormous eating quadrupeds. tail. It was particularly adapted to live in swampy districts The MastODON was another species of eli,hant, about the and in marshes, where it fed on the roots and the leaves of size of the present elephants and with mammillated teeth. It aquatic plants. lis body was about eight feet long, with a abounded in the districts now called North America; where skin nearly naked, and having its ears very short. Except perfect skeletons of it have been found in salt marshes, which the kangaroo, no living animal is known to have so long and so it visited for the sake of the salt, and where it frequently sunk powerful a tail.
in deep mud and perished. Some of these marshes are known The second species of Anoplotherium is called the Xipho- to be forty miles long by about twenty miles broad. In don, from tipos, xiphos, a sword, and howv, odôn, a tooth, Warren County, New Jersey, six skeletons of the same masa creature very different in size, in proportions, and in habits todon were found, six feet below the surface, five of them lying from the first species. The graceful elegance of its skeleton | together. reminds one of the gazelle. It might be about as high as a The name is given on account of its teeth being like paps goat, but its head and trunk indicate a smaller animal. It from uartos, mastos, breast or pap, and bowv, tooth. lived on the banks of lakes and rivers, and on the borders of This species continued to live through the Pleistocene periods, marshes, feeding on aromatic herbs and the young buds of almost down to the human epoch, accompanied by some of the trees. It was covered with a short hair, and was most likely a animals which are now existing.