Page:Encyclopædia Britannica, Ninth Edition, v. 9.djvu/401

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F R F E 387 types of Foraminifera, especially Globigerina (fig. 14), a conclusion to which Professor W. C. Williamson was in dependently led by his study of the " Levant mud," a white chalk-like deposit at present in progress of formation on the comparatively shallow bottom of the eastern end of the Mediterranean. 1 This conclusion has been fully borne FIG. 37. Microscopic Organisms in Chalk from Graveseml: a, 6, c, <i, Texlularia globulosa; f, e, e, e, Rotalia aspera; f, Textularia aculeata; y, PlanuJaria he.ras ; k, A aricula. out by the deep-sea soundings and dredgings since carried on which have established the fact that large areas of the great ocean-basins are covered to an unknown thickness by a Foraminiferal ooze, which, when dried, corresponds in every particular with ordinary Chalk. And there is, more over, very strong evidence that this deposit is not a repeti tion of the old Chalk formation, but an actual continuation of it over areas which have undergone no such upheaval as that which raised the chalk of Europe, Asia, and America into dry land. Not only the Chalk, but the subjacent Greensand appears to have originated in great degree in Foraminiferal life, its glauconite grains being (in the localities in which they seem to have undergone least attrition) internal casts of easily-recognizable types of that group, formed by the process already described as still going on upon parts of the existing sea-bottom. Various larger types of all the principal groups of Foraminifera occur in different parts of the Cretaceous formation, the "porcel- lanous " sub-order being now fully represented. The highest development of the Foraminiferal type, as measured by the extraordinary abundance of its largest and most complex examples, seems to have been attained in the early Tertiary period, to which belongs the vast formation of Nummulitic Limestone, forming a band often of 1800 miles in breadth, and sometimes attaining several thousand feet in thickness, which may be traced eastwards from the Atlantic shores of Southern Europe and Northern Africa (the Pyramids being built of this rock, and on a terrace formed by it) through Western Asia to Northern India and China, and likewise over largo areas in North America thus taking, to use the words of Sir Charles Lyell, a far more conspicuous part than any other Tertiary group in the solid framework of the earth s crust. In some localities it seems to lie comformably upon Cretaceous strata, so as to establish the continuity between the latest Secondary deposits and the earliest Tertiaries formed in the deep sea. In some localities this Limestone is essentially composed of an aggregation of Nummulites (including, however, the fossil 1 Memoirs of the Manchester Philosophical Society, vol. viii. remains of higher organisms), the spaces between the large and entire shells being filled in by minuter forms and by the debris of previous generations of the larger ; whilst in other localities the Nummulites are replaced, wholly or in part, by Orbitoides and Orbitolites. In the Paris basin the Nummulitic Limestone is represented by the Calcairs grassier, which is for the most part of Foraminiferal origin. Its lower calcareous beds are chiefly Nummulitic; but in the middle part of the series we find the Milioline group pre dominating, some of its beds being chiefly composed of Orbitolites, whilst others (notably those of which a large part of Paris is built) are essentially made up by the aggregation of the smaller Miliolce. The calcareous sand of Grignon, which consists in great part (like many beds of the Oolitic formation) of shells comminuted by the action of the waves, contains a great abundance of Foraminifera, among them the large and complex Dactylopora, which is only represented at the present time by a minute form of extreme simplicity. In various marine deposits of the middle and later Tertiary periods, especially thosi which form the slopes of the Apennines, Foraminifera are abund ant ; but the larger forms gradually give place to the smaller, and the Foraminiferal fauna progressively approxi mates more closely to that of the present time. Altogether it would certainly be not too much to affirm that, so far as we are justified by positive evidence, no single group of the Animal Kingdom has contributed, or is at present contributing, so largely as the one of which a sketch has now been given to the formation of the crust of the earth, byseparating carbonate of lime from its solution in sea water, and thus restoring to the solid form the vast quantity of that material which is continually being taken up in solution, and discharged into the oceanic basin, by the percolation of rain-water through the calcareous strata which have been elevated into dry land, which are thus undergoing continual degradation. And if the origin of the great part of the Carboniferous Limestone in Foramini feral rather than in Coral life be accepted as probable, the share taken by Foraminiferal life in this process during the Palaeozoic period would appear to have been fully equalled by that which it took in the formation of the Chalk, and in the production of the Nummulitic Limestone, of more modern geological epochs. (w. B. c.) FORBACH, a town of Lorraine, Germany, the chief town of a circle, is situated on an affluent of the Rossel and on the Metz and Saarbriicken Railway, about 51? miles south-west of Saarbriicken. Its industries include brew ing, tanning, and the manufacture of glass, soap, and pasteboard. At a short distance from the town are the large iron-works of De Wendel, Enkel, & Company, which employ about 1500 workmen. There are also large coal mines in the vicinity. Forbach possesses a real school, a higher female school, a Catholic and two Protestant churches, and a synagogue. After the battle on the neigh bouring heights of Spicheren, August 6 ; 1870, in which the French under General Frossard were defeated by the Germans under Prince Frederick Charles, the town was occupied by the German troops, and at the conclusion of the war it was annexed to Germany. The population in 1875 was 6178. FORBES, ALEXANDER PENROSE (1817-1875), bishop of Brechin, was born at Edinburgh, June 6, 1817. He was the second son of Lord Medwyn, a judge of the Court of Session, and grandson of Sir William Forbes of Pitsligo. He studied first at the Edinburgh Academy, then for two years under the Rev. Thomas Dale, the poet, in Kent, passed one session at Glasgow university, and, having chosen the career of the Indian civil service, completed his studies at HaiIej T bury College. In 1836 he went to Madras, but in consequence of ill-health, the result of the