« EelmineJätka »
remains of Encrinites, a variety of Crinoid wonderfully numerous in this formation. These marine animals closely resembled plants, hence the name "stone lilies," and, like plants, were fixed to one spot.
They consisted of innumerable articulating joints placed one above another upon a base or root attached to the sea-bottom. This stem, often several feet in length, was surmounted by a cup-shaped arrangement (pelvis) containing the body of the animal, from which issued long jointed tentacula or fingers, capable of being extended horizontally for the purpose of allowing it to catch its prey. Not unfrequently the stems consisted, as in the species Moniliformis, of several thousand Entrochi or joints, and through the whole series ran an alimentary canal connecting the base with the stomach. The holes in the joints caused by the existence of this canal suggested to the former
C. rugosus, Platycrinus lævis, Foteriocrinus tenuis, Cyathophyllum turbinatum, Plates of Archæocidaris urii, Fenestella membranacea, Productus longispinus, P. semireticulatus, Spirifera lineata, S. glabra, S. trigonalis, Orthis Mitchilini.
The plates of the Archæocidaris are usually found singly in the looser shale, and are highly interesting as being the remains of one of the very earliest forms of the family Cidaris (Echinodermata). These will probably be far better understood by breaking in pieces and comparing the separate sections or plates
of one of our estuarine echinoderms, say the Echina sphæra.
It may be mentioned that on the shore within a mile from this quarry is an excellent illustration of the change which a sedimentary rock undergoes by contact with an igneous one. In a narrow stretch of coast-line not more than a furlong in length we have a sandstone gradually developing into a quartz rock, yet so imperceptibly does the change take place as to completely defeat any attempt to locate the spot at which the sandstone ends and the quartz rock begins.
Directly north of Invertiel, about 15 miles distant, is the East Lomond Hill, rising 1,471 feet above the level of the sea. The lower and middle portion of this hill, which was in 1881 one of the chief stations of the Ordnance Survey, is composed of Calcareous Sandstone, representing probably some of the lower beds of the English carboniferous rocks, but at the height of 1,200 feet the limestone crops out and forms
It is worthy of note that this is one of the highest situated exposures in Scotland from which fossils have as yet been obtained. In many places the limestone is quite bare, with no soil or covering above it, and yet from a thin bed of stone or "blae," quite a large number of shells may be seen, of forms varied and perfect, and but little injured or weathered by their long exposure to the atmosphere. They, however, usually break whenever an attempt is made to extract them from the matrix, and it is only by exercising the greatest perseverance and patience that fairly good specimens of any of the numerous forms of Productus, Spirifera, Rhynconella, etc., can be carried away. Over a century ago this hill was worked for lead, which in the form of galena also yielded silver. The ore, now unprofitable for working, was massive and in hexahedral crystals.
In the west of Fife are the limestone quarries of Limekilns and Charleston, about a mile apart. At the former place the rock was worked so long ago as the 17th century, and must have been an important article of industry and commerce even fifty years ago. Its value to this once thriving village may be better understood by mentioning that from 1840 to 1850 the average annual output of limestone exceeded
a mile has been altogether changed. Instead of a gradually rising shore or "talus," we have a thin stretch of undulating ground, backed by a steep precipitous ridge or cliff in several places upwards of 120 feet high. This is one of many such examples which help to show us how very greatly the aspect of a locality may be permanently changed by mining or quarrying operations conducted from the surface. The exposure consists generally of several beds of limestone dipping to the north-west at an angle of 120, the visible depth being about 60 feet. These beds in their turn are covered by 35 feet of shale more argillaceous than carboniferous in its composition. The limestone in appearance is very similar to that already described, the colour perhaps being a
On the south side of the Forth we have the rock again exposed in the quarries north-east of the important mining district of Bathgate. The ridge or series of hills locally known as the Torphichens form part of the south rim of the Forth basin, and rise to a height of 600 feet above the sea-level. The limestone in this neighbourhood consists of a series of beds 60 feet thick, is of the usual grey colour, but somewhat softer in texture, yielding more readily to weathering influences, and becomes of a black-yellow tint on decomposition. Possibly to the student just commencing his researches among the Carboniferous limestone no better locality than that of Bathgate could be desired, as the exposures are both numerous and easy of access, while the profusion of organic
Fig. 49.-Spirifera striata, b and c showing internal coils.
shade darker owing to the presence in the rock of a small percentage of naphtha. Organic remains are somewhat rare in the lower beds, but of those occasionally found most are in a fairly satisfactory state of preservation. The upper massive beds yield good and large Productus longispinus, P. sinuatus, P. martini, and P. fimbriatus; the thin beds of calcareous shale contain species of Tubipora, Cyathophyllum, Clisiophyllum, Turbinolia, Fungites, (sheep's-horn), and various parts of dispersed encrinites; while from the nodules of red-coloured argillaceous ironstone found in the upper "blaes" the writer has obtained very perfect and well-defined specimens of Conularia quadrisulcata, Orthis resupinata, Spirifera lineata, and Strophomena sp.
Fig. 50.-Productus giganteus.
(From Taylor's "Common British Fossils.")
remains is such as to lend every encouragement to those who desire to wield hammer and chisel to advantage. At present, operations in the once extensively worked quarries are all but stopped in consequence of the small demand for lime and the keen competition of more favourably situated limeworks. But it is impossible to wander among the various workings without noticing on every hand signs of the great amount of material which has been extracted. Lead was at one time obtained here in small though not very continuous veins, and this in turn yielded a small percentage of silver. The argentiferous ore was long worked in one of the quarries still bearing the name of "Silver Mine," situated a few hundred yards north-west of the
reservoir immediately above the town, and near to the Bathgate and Linlithgow road. After yielding a comparatively large quantity of silver it ultimately ceased to give a supply great enough to be remunerative, and operations at length were suspended. In 1871 further explorations were made, and several deeper pits with numerous ramifications opened, but beyond obtaining a small and unsatisfactory amount of lead, silver, and platinum ore, the venture was unsuccessful, and the place was finally abandoned. Evidence was, however, adduced during the search, which proved conclusively that the same vicinity had been worked for silver so far back as the 15th and 16th centuries. The specimens now to be obtained comprise barytes (heavy-spar) calc-spar, pearl-spar, and dolomite, while a closer examination among the seams of friable limestone will be rewarded by the discovery here and there of small pieces of lead ore, zinc ore, and pyrites. The fossils, as we have already mentioned, are very numerous, and almost every stone wall in the immediate neighbourhood bears witness to this statement. But while the specimens are so
Fig. 51.-Tooth of Rhizodus Hibberti.
very general it cannot be said that the species are proportionably varied. Productus giganteus, Cyathocrinus planus, and Platycrinus lævis are unusually common, the first mentioned being present in such quantities as to cause the rock to be well qualified for the name "Productus" limestone. In fact, it seems more abundant here than in any other series of quarries under our notice, but it is unfortunately very difficult to extract. Other fossils obtainable include Spirifera striata, (comparatively rare in Scotland), Productus semireticulatus, and the Polyzoa Fenestella membranacea.
Before taking leave of the carboniferous limestone of the Forth district, it is necessary for us to consider briefly a sub-deposit exposed at Burdiehouse, Newbigging, and other places, to which the terms
"Encrinital, 99.66 Productus," and "Mountain" would be altogether inappropriate, but which must certainly be included under the term "Carboniferous." This deposit, commonly known as the Burdiehouse Limestone, was first brought prominently before geologists by the late Dr. Hibbert in 1835. It has a dull, earthy, light blue appearance, is exceedingly hard and brittle, breaks with a conchoidal fracture, and the beds vary in thickness from 20 to 30 feet. Where found, it usually occurs alternating with oil-producing shales, directly above the calciferous sandstones, and to a limited extent contains fossils common to both rocks, notably Sphenopteris affinis and S. bifida. From the nature of the embedded remains it has been considered to be of fresh-water or estuarine origin. Remains of microscopic crustacea closely resembling in general structure those at present existing in freshwater lakes abounding in decaying vegetable matter, occur in myriads. Teeth of ganoid fish, Rhizodus Hibberti, and of Callopristodon pectinatis, and Nematoptychius sp. are occasionally found, the firstnamed being usually very perfect.
Though this formation is particularly enticing to the paleontologist, it may not be altogether out of place to warn the student against building up a too exaggerated idea of what he may be able to obtain from the rock during a chance visit of two or three hours' duration. It is quite possible that he may succeed in becoming the possessor of a good-sized specimen of tooth of Rhizodus or other fish, but it is equally probable that he may have to remain satisfied with less enticing relics, made up, perhaps, of some of the more common fern remains. If, however, the place visited be Burdiehouse itself, he will be able to find something to reflect upon during his journey back to Edinburgh (five miles) by knowing that the quarry and its contents have been studied by the eminent geologists, Sir Roderick Murchison, Hugh Miller, Agassiz, and Drs. Fleming and Buckland.
(To be continued.)
FAMINE IN THE LAND.
E may gather from the accounts and papers and "Imperial Gazetteer" that the following were years of famine in India :-1396 to 1407, 1460, 1520, 1629-31, 1650, 1686, 1746, 1755, 1759, and 60, 1770, 1773, 1783, 1790-92, 1803, 1807 and 13, 1824, 1833, 1838, 1845, 1847, 1854, 1860 and 61, 1866, 1869, 1873 and 74, 1876-1878. In the Delhi market the price of wheat, according to Mr. Stanley Jevons, was highest in 1763, 1773, 1783, 1792, 1803, 1809 and 12, 1820 and 26, 1834; between which dates and the sun-spot series there is a more or less exact coincidence, some local displacement being marked by the years 1792 and 1872. Famines in India, then, may be expected at the epochs of most and fewest sunspots, and corn in particular, where grown, may be
WRITTEN IN THE SUN-SPOTS.
"Decidimus quo pius ENEAS quo dives Tullus et Ancus, Pulvis et umbra sumus "-HOR.
574 Tyre taken.
Darius the Second.
Tribunicia Potestus, 446.
Date of Daniel.
Leges agrariæ; Darius dies.
Tarquinius Superbus deposed, 509.
Madness and death of Cambyses.
Gyges dies, 663.
Insurrection in Assyria.
Hezekiah dies; Assaranadina, 699.
Tarentum founded, 707.
Deioces; Merodach-baladin deposed, 710.
742 Ahaz; Tiglath-pileser.
Uzziah and Menahem die, 759.
Zechariah assassinated, 773.
Jeroboam the Second dies.
720 Fall of Samaria, 721.
728 Ahaz dies.
739 Pekah murdered.
Tarquinius Priscus dies, 579.
Destruction of Jerusalem.
Aurora Borealis ; Ezekiel ; Eclipse, 597. m
Nineveh destroyed, 606.
Ancus Martius dies.
Cyrene founded by Delphian Oracle.
Tullus Hostilius dies; 641, Josiah.
915 Jehosaphat, 914.
Elah murdered; Baasha died, 930.
Binlik hish II. dies, 936.
Rehoboam dies, 958.
Famine of Amos, 787.
Plague in Assyria.
885 Jehoram dies, 884.
Famine in Samaria.
896 The prophets urge Ahab to battle. Shalmaneser, 905.
Circa, depositions, plague in Assyria.
Shalmaneser V. dies, 818.
Jehoahaz died, 840.
Jehoram murdered, 883.
Elijah's famine; visits Horeb.
"The angel at the threshing-place." "A sound in the mulberry tops."
Saul dies, 1056.
Codrus; Inarchus, 1856.
"The angel at the threshing-place."
Sinai, Burning Bush, and Plagues, 1491.
m 1709 Joseph's famine, 1707.
This Table is founded on the conception of the periodical recurrence of Famines, and may be extended. The notation employed is the Mean Sun-Spot one of Astronomy, which here represents the Jubilee Years, Prophetical Numbers, and other dark Figures in general. The passage from most to fewest sun-spots is calculated as transpiring every eleven years, the epoch of Fewest (m) being indicated eight years after each maximum (M).