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of darker-coloured calcareous shales. Mineralogically
3.5 Various (sulphur, oxide of iron, &c.) 2.5
inhabitants of some limestone districts the idea of their having at one time been beads, and indeed they have often been used as such. It is to these that Sir Walter Scott alludes in “ Marmion.”
“On a rock by Lindisfarn, St. Cuthbert sits and toils to frame
The sea-born beads that bear his name.” Myriads of these Encrinite stems and joints, the latter varying in diameter from a line to an inch, are crowded into the limestone of Invertiel and other places, though the most perfect examples are those found in the looser calcareous shale. The Encrinite is never found entire at this and adjoining quarries, but bases and parts of the pelvis and tentacula are by no means rare. Other characteristic fossils found here include, Cyathocrinus planus, C. tuberculatus,
remains of Encrinites, a variety of Crinoid wonder. fully 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
Fig. 41.-Stem of Poteriocrinus crassus. (From Taylor's
("Common British Fossils."') placed one above another upon a base or root attached to the sea-bottom. This stem, often several feet in C. rugosus, Platycrinus lævis, Foteriocrinus tenuis, length, was surmounted by a cup-shaped arrangement Cyathophyllum turbinatum, Plates of Archæocidaris (pelvis) containing the body of the animal, from which urii, Fenestella membranacea, Productus longispinus, issued long jointed tentacula or fingers, capable of P. semireticulatus, Spirifera lineata, S. glabra, S. being extended horizontally for the purpose of allow- trigonalis, Orthis Mitchilini. ing it to catch its prey. Not unfrequently the stems The plates of the Archæocidaris are usually found consisted, as in the species Moniliformis, of several singly in the looser shale, and are highly interesting thousand Entrochi or joints, and through the whole as being the remains of one of the very earliest forms series ran an alimentary canal connecting the base of the family Cidaris (Echinodermata). These will with the stomach. The holes in the joints caused by probably be far better understood by breaking in the existence of this canal suggested to the former pieces and comparing the separate sections or plates
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
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
a belt over 12 feet thick, the rock inclining gently to the south-east.
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.
Fig. 47.- Transverse section of Clisiophyllum.
15,000 tons, while the value of the raw material previous to burning and shipment amounted to nearly £4000. The rock has been wrought from the face of the outcrop, north-east to south-west, and very close to the shore. Step by step the workings have been carried westwards towards Charleston, the site of the present very restricted operations. The result is that the appearance of the coast-line for upwards of
a mile has been altogether changed. Instead of a On the south side of the Forth we have the rock gradually rising shore or “talus," we have a thin again exposed in the quarries north-east of the stretch of undulating ground, backed by a steep important mining district of Bathgate. The ridge or precipitous ridge or cliff in several places upwards of series of hills locally known as the Torphichens form 120 feet high. This is one of many such examples part of the south rim of the Forth basin, and rise to which help to show us how very greatly the aspect a height of 600 feet above the sea-level. The limeof a locality may be permanently changed by mining stone in this neighbourhood consists of a series of or quarrying operations conducted from the surface. beds 60 feet thick, is of the usual grey colour, but The exposure consists generally of several beds of somewhat softer in texture, yielding more readily to limestone dipping to the north-west at an angle of weathering influences, and becomes of a black-yellow 12°, the visible depth being about 60 feet. These tint on decomposition. Possibly to the student just beds in their turn are covered by 35 feet of shale commencing his researches among the Carboniferous more argillaceous than carboniferous in its composi- limestone no better locality than that of Bathgate tion. The limestone in appearance is very similar to could be desired, as the exposures are both numerous that already described, the colour perhaps being a and easy of access, while the profusion of organic
shade darker owing to the presence in the rock of a remains is such as to lend every encouragement to small percentage of naphtha. Organic remains are those who desire to wield hammer and chisel to somewhat rare in the lower beds, but of those advantage. At present, operations in the once occasionally found most are in a fairly satisfactory extensively worked quarries are all but stopped in state of preservation. The upper massive beds yield consequence of the small demand for lime and the good and large Productus longispinus, P. sinuatus, keen competition of more favourably situated limeP. martini, and P. fimbriatus ; the thin beds of works. But it is impossible to wander among the calcareous shale contain species of Tubipora, various workings without noticing on every hand Cyathophyllum, Clisiophyllum, Turbinolia, Fungites, signs of the great amount of material which has been (sheep's-horn), and various parts of dispersed en- extracted. Lead was at one time obtained here in crinites ; while from the nodules of red-coloured small though not very continuous veins, and this in argillaceous ironstone found in the upper “blaes ” turn yielded a small percentage of silver. The the writer has obtained very perfect and well-defined argentiferous ore was long worked in one of the specimens of Conularia quadrisulcata, Orthis resupi. quarries still bearing the name of “Silver Mine,” nata, Spirifera lineata, and Strophomena sp.
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
" " Productus,” and “ Mountain" would be altogether inappropriate, but which must certainiy 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 ciosely 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 palæontologist, 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 its contents have been studied by the eminent geologists, Sir Roderick Murchison, Hugh Miller, Agassiz, and Drs. Fleming and Buckland.
(To be continued.)
Fig. 57.-Tooth of Rhizodus Hibberti.
FAMINE IN TIIE LAND.
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 scmireticulatus, 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, New. bigging, and other places, to which the terms
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 ihe 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-Srots.
596 Aurora Borealis ; Ezekiel ; Eclipse, 597. m 907 Elijah's famine ; visits Horeb.
632 | Cyrene founded by Delphian Oracle.
Elah murdered; Baasha died, 930. 640 Tullus Hostilius dies ; 641, Josiah. M
Binlikhish II, dies, 936. 643 Manasseh dies, 644; Amon, 642. M 959
Rehoboam dies, 958.
“The angel at the threshing-place." 698 Hezekiah dies; Assaranadina, 699. M 1047
" A sound in the mulberry tops.”
M 1058 | Saul dies, 1056.
1094 Saul, 1095.
M 1256 “The angel at the threshing-place.” 720 Fall of Samaria, 721.
1489 Sinai, Burning Bush, and Plagues, 728 Ahaz dies.
1491. 739 Pekah murdered.
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).