186 



THE FAMER'S MONTHLY VISITOR. 



caulodon allied to tlie mastodon — four of the 

 cut kind some us large as the lion, and one spe- 

 cies allied to the dog, but e<|uully extraordinary 

 in size with the others. These with the hip- 

 potherium allied to the lior«e — three species of 

 the hog, one of the bear and one of the glutton 

 formed the principle part of those animals that ten- 

 anted our globe in the second period of those 

 tertiai-y deposits which i)revail so generally in 

 the Gorman Empire. The dinotherium was the 

 largest of all terrestrial mammalia among the 

 fossd remains yet found. The lengtli extended 

 to eighteen feet and a skeleton head tliat was 

 found at Eppleshiern measured more than a yard 

 ill length and as much in breadth. 



In the third and fourth divisions of the tertia- 

 ries or pliocene period, the palceotherian family 

 had become extinct ; but a new genus, the masto- 

 don, as also the megatherium and megalonyx 

 with the still e,\isting elephant, rhinoceros, hip- 

 popotamus, tapir, horse, ox and deer were found. 

 The fossil remains of the megatherium are found 

 in the great sandy plainsof the Pampas, in Buenos 

 Ayres to an extent of six himdred miles. It was 

 a gigantic animal larger than the rhinoceros and 

 api)roximating in form to the anomalous genera 

 of the sloth, armadillo and chlnmyphorns. 



The mastodon, so called from the monstrous 

 size of its molar teeth is the same animal that 

 has been described in the United States by the 

 natne of the mannnoth. The tirst fossil 

 skeleton of this animal was found on the banks 

 of the Ohio by a French Officer in 1750, who 

 sent the bones to Paris. The mastodon, though 

 differing in many important particulars, has, not- 

 withstanding, a great general resemblance to the 

 elephant. Six species have already been discov- 

 ered, the largest of which is the mastodon gigan- 

 tium or mannnoth of America. The megalonyx 

 found also in the United States h.id the same 

 general resemblance to the megatherium that the 

 mastodon had to the elephant, but was much 

 smaller. As the saurians attained their maxi- 

 mum size in the secondary depo.sits, since which 

 they have constantly degeneiated, so likewise did 

 the quadruped manmialia find their most con- 

 genial clime and productive soil in the formation 

 of the tertiaries during the last revolutions of 

 which many of them disappeared leaving only 

 the fossil relics of their giant skeletons to sliow 

 that they ever had existence. Tin; palcothe- 

 rii (linotherii ; ma.stodon and megalonyx with 

 many other genera have become extinct every- 

 where. The elephant and rhinoceros are found 

 only in Africa and Asia allhou;;h their fossil re- 

 mains are found throughout Europe. We have 

 no evidence that these extinct genera were ever 

 cotcniporaneous with man, no relics of the hu- 

 man race ever having been found mixed U|) with 

 their remains ; and the proof remaining clear and 

 positive that a series of changes preparing the 

 earth for habitability was in progress ibr a long 

 period of time anterior to human existence ; anil 

 that we were ])laced here after the great convul- 

 sions of nature had matured the work of reno- 

 vation and those giant uiiimals incompatible with 

 human safety had ceased to exist. 



A sixth residt was the remarkable changes jiro- 

 duced by volcanic agency during the organic age 

 and even down to the present jieriod. Previous 

 to iliis the effects of conflicting elements of heat 

 and cold had been confined to the surfice.or near 

 the .surljice of the cirth. Jt might be compared 

 to the action water would have upon a ball of 

 heated metallic matter when thrown upon it. 

 The action w culd be general over the ciutli and 

 the crust oxidated as it was formed. Yrt from 

 the slow reduction of temperature and the thin- 

 ness of the crust, the elevations and de]>re^^sionK 

 would be comparatively small. Hut at the com- 

 mencement of the organic age the crust had ob- 

 tained a depth and firnmess sutlicient to oppose 

 a hairier to this general action ; and a state of 

 comparative repose took place. Still we find 

 those agents had only slumbered for a time ; their 

 energies had not ceased ; Ihey were soon awak- 

 ened to renewed and more terrific action. Their 

 operations were changed however from the sur- 

 face to beneatli the crust and a system of subter- 

 ranean dynamics was carried forward which 

 miglit be compared to a globe of coinjinct mate- 

 rials filled near the surface with detached pow- 

 der magazines with slow matches of unequal 

 leiistli, burning down to the explosive m:iterials. 

 They were not like the esirlier jilieiionienii si- 



multaneous in time, or general in their opera- 

 tions; but vastly more powerful in their effects. 

 The face of the earth was again changed. The 

 volcanic upheavitigs elevated the recently formed 

 crystaline rocks up through some basins and 

 pouring their contents into the cavities of oth- 

 ers would form those stratified diluvial remains 

 which we now find as the aggregate of their de- 

 posits. These wo^ild be compooed of sands, 

 the fragments of primitive rocks anil animal re- 

 mains. In some, the deposits of salt which had 

 accumulated to a vast amount would form a part 

 of the stratified diluviie while in others the ve- 

 getation of the isthmuses which bordered these 

 basins would be swept into their cavities and 

 form the extensive coal beds now found in dif- 

 ferent jiarts of the world. 



" In the state of tranquil equilibrium (says Mr. 

 Buchland) which our planet has attained in the 

 region we inhabit, we are apt tp regard the foun- 

 dation of the solid earth, as an emblem of dura- 

 tion and stability. Very different are the feel- 

 ings of those, whose lot is cast near the foci of 

 volcanic eruptions. To them the earth affords 

 no stable resting place, but duringthe paroxysms 

 of volcanic activity reels to and fro, and vibrates 

 beneath their feet. They behold cities over- 

 thrown and buried in ruins, while the earth 

 yawning with dreadful chasms, converts the seas 

 into dry land, and the dry land into seas. To 

 the inhabitants of such districts we speak a lan- 

 guage which they fully comprehend, when we 

 describe the crust of the earth as floating on an 

 internal nucleus of molten elements ; for they 

 have seen these elements burst forth in streams 

 of burning lava ; they have felt the earth be- 

 neath them quivering and rolling as if upon the 

 the billows of a subterranean sea ; they have seen 

 mountains raised and vallies depressed almost 

 in an instant ot time ; and they can duly appre- 

 ciate from sensible experience the force of the 

 terms in which geologists describe the tremu- 

 lous and convulsive agitations of the earth dur- 

 ing the passage of its strata from below the bot- 

 tom of the seas where they had their origin to 

 the plains nnd mountains in which they find their 

 present |)lace of rest." 



It is evident al.so tliat the inimary rocks, dur- 

 ing their elevation would be fractured and dislo- 

 cated, and these fractures being filled sometimes 

 from helow with igneous fluid matter, and in oth- 

 ers from above with aqueous deposits would 

 form the dikes and faults which are (bund in all 

 stratified tbrmations and which are of such im- 

 portance to the miners and hydrographic engineer, 

 For instance in a coal field, had the strata of 

 shale and giit that generally prevail alternately, 

 been continuously united without fracture, the 

 quantity of w ater that would have i)enetrated 

 from the surrounding country into any considera- 

 ble excavation that might be made in the porous 

 grit beds, would have overcome all power of ma- 

 chinery, that could ])rofitably be applied to the 

 drainage of a mine. Whereas by the simple ar- 

 rangement ot a system of faults, the water is 

 admitted only in such quantities as are within 

 control. Thus the component strata of all bn- 

 siii formations are divided into insulated masses 

 or sheets of rock, of irregular form and area ; not 

 one of which is continuous in the same plane 

 over any very large district, but each is separa- 

 tpd from its next adjacent inais by a dam of clay 

 operating as natural coffer dams, impenetrable to 

 water and filling the fissure produced by the frac- 

 ture which caused the fault. We niso find the 

 rocks adjacent to modern volcanic craters, inter- 

 sected by rents and fissures which have been 

 filled with injections of more recent lava, form- 

 ins transverse walls or dikes ; and as similar 

 dikes occur also not only in districts occupied by 

 basalt and trap rocks at a distance from the site 

 of any modern volcanic activity, but also in stra- 

 ta of every formation fi-om the most ancient 

 transition to the most recent tertiary, and as there 

 are insensible gradations from a state of com- 

 pact lava through the varieties of greenstones, 

 serpentines and porphyries to granite, we refer 

 these dikes not only to a common igneous, but to 

 a volcanic origin. We therefore learn that eleva- 

 tions and subsideries, inclinations and contor- 

 tions, fractures and dislocations, are phenomena 

 in geological history, which although at first sight 

 jireseiit the appearance of disorder and confus- 

 ion, yet when fully understood, are found to be 

 eovorned bv general laws, and demonstrate the 



existence of order, and method, and design, even 

 in the operations of the most turbulent and ap- 

 parently the most chaotic, among the many 

 mighty physical forces which have affected the 

 terraqueous globe. The subsequent changes 

 were the result of volcanic action. 



And the severUh in order of time was the for- 

 mation of vast beds of mineral coal. The veget- 

 ation swept into the basins by the upheavings of 

 the primitive rocks; and buried under the detri- 

 tus of marine diluviae would not like the vegeta- 

 tion of modern times undergo rapid decay yield- 

 ing back their elements to the soil and atmos- 

 phere f iom whence they were derived ; but trea- 

 sured up in subterranean storehouses, would be 

 transformed by the united influence of confine- 

 ment, heat and pressure, into those combustible 

 elements which now contribute so largely to the 

 comfort of man as the sources of heat and light, 

 wealth and power. JVliscroscopic observations of 

 late years have proved not only the vegetable na- 

 ture both of anthracite and bituminous coal, but 

 mineralogists have generally been able to distin- 

 guish the peculiar vegetable which entered sev- 

 erally into their composition. 



The disposition of the earth in the form of 

 troughs or basins before mentioned as being of a 

 peculiarly interesting character, and which is 

 found to be common to all formations, has been 

 more particularly demonstrated int he carbonifer- 

 ous series of strata from the circumstance that 

 the valuable nature of beds of coal often causes 

 them to be wrought throughout their whole ex- 

 tent. This disposition of the strata causes the 

 coal beds to be brought to the surface 

 arountl the circumference of each basin and 

 renders them accessible at the same time by 

 sinking mines in almost every part of their res- 

 pective areas. The carboniferous system of the 

 transition series is now known from the aecumu- 

 lated experience of many years to bo the only 

 strata where productive coal mines on a large 

 scale have ever been discovered. The peculiar 

 plants of that period, and the chemical changes 

 to which they were subjected fbr a period of 

 time apparently immense in its duration, and un- 

 der circuinstaiices far distant from what would 

 occur during the secondary and tertiary depos- 

 ites, go conclusively to prove, that this formation 

 in its relative order is the only one in existence. 

 Examples of coal to be sure occur in the secon- 

 dary strata, yet they are few and insignificant, 

 while the lignites of the tertiaries although they 

 occasionally present small deposites of compact 

 and useful fuel, yet tliey exert no important influ- 

 ence on the economical condition of mankind. 

 Probably the most characteristic type of the con- 

 dition and circumstances of the carboniferous 

 strata is found ill the north of England. The 

 stratified basin fiom New Castle upon Tyne to 

 cross Fells in Cumberland gives an average thick- 

 ness along the whole of this sectional line of 

 four thousand feet. This enormous mass is com- 

 posed of alternating beds of shale or indurated 

 clay, sandstone limestone, and coal. The indi- 

 vidual strata are thirty-two beds of coal, sixty- 

 two of sandstone, seventeen of limestone, one 

 intruding bed of trap and one hundred and 

 twenty eight beds of shale and clay. 



To illustrate the importance of dikes and 

 faults in these coal fields, it may be mentioned 

 that a shaft was began at Gasfbrth near New 

 Castle in 1825 on the west side of the ninety 

 fathom dike which was so inundated with water 

 that it was soon found necessary to abandon it. 

 Another shaft was then commenced on the oth- 

 er side of the dike only a few yards fiom the 

 former ; in which they have descended twelve 

 hundred feet without suffering any impediment 

 from the waters so abundant in the first. 



The cighlh result of this phenomena of chan- 

 ges was the fbrinalion of vast mines of chloride 

 of sodium or table salt fiom the volcanic agen- 

 cies belbre mentioned. These undoubtedly 

 were formed in the first instance by the profuse 

 and intense evaporation of those shallower seas 

 highly charged w ith saline ingredients ; not deep 

 enough for the support of animal life ; hut acted 

 upon b}' the elevated temperature both of the 

 earth and atmosphere which then prevailed, 

 would form immense incrustations of that min- 

 eral which being thrown from their native beds 

 into the reservoirs of other basins and acted 

 upon bj' heat and pressure would occupy their 

 place in the Poioilitic strata where they are now 



