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If there is one canon in gsology more firmly established than another, it is that fossils indicate a certain definite time in the earth's history, that the various species which they represent appeared, lived, and died out at certain definite times, and that, therefore, fossil evidence has come to be considered the most trustworthy of all evidence as an index to the age and succession of the various rock-formations. In fact, that, as Dr. Mantell put it, fossils are the “Medals of Creation.” Associated with this there is another belief, viz., that the various formations succeeded each other in a certain distinct order, one at a time; that each formation was newer than that below, and older than that overlying it, but was contemporaneous with neither. With these beliefs, it appears, however, that Sir Archibald Geikie does not agree, at least, judging from the third edition of his “Text Book of Geology,” 1893, according to which fossils cannot be depended on as indications of the age of rocks, as they may be found in formations to which they do not really belong; and that the difference between two formations may be geographical rather than geological, as two entirely separate formations may have been formed contemporaneously in different, though possibly neighbouring, geographical areas. Thus, at page 665, it is stated that in Bohemia and Russia some of the most characteristic Upper Silurian organisms are found beneath strata full of Lower Silurian life forms. At page 760, when speaking of the close This 250-word extract was created in the absence of an abstract

These sections are situated about seven miles south of Glasgow, a little to the north-east of the Eaglesham Road Station, on the Busby and East Kilbride Railway, and at a height of from five to six hundred feet above the level of the sea. At this place we are near the south-western edge of the Lanarkshire coalfield, and a good idea may be formed of its transverse extent by ascending any of the hills in the district; as, for instance, that to the east of Thornton farm-house. In the distance to the west we descry the Bowling hills and the range of mountains from Ben Voirlich to Ben Ledi, while on the north the Clyde basin is bounded by the trap hills of Campsie and Kilsyth. A corresponding range of trap hills runs behind us on the south. The strata here dip under all the intermediate strata and reappear near the base of the Campsie hills, as we shall afterwards have occasion to notice. Between these points the strata are overlaid by part of the lower limestones, the middle ironstones, and the upper limestones, as well as by strata corresponding to the millstone grit, and the whole, or nearly the whole, of the upper coal measures. The surface of the ground is of an undulating character, rising gradually towards the south. The sections to be described occur at four quarries, viz.,—Thornton, Thornton Hall, Braehead, and Phillipshill—the first being on the southern, the second on the western, and the third and This 250-word extract was created in the absence of an abstract

In the third edition of his Text-Book of Geology, Sir Archibald Geikie has discussed the question whether fossils can be wholly depended upon to indicate the age of rocks when similar or representative species are found in areas wide apart. Thus he tells us (p. 665) that in Bohemia and Russia some of the most characteristic Upper Silurian organisms are found beneath strata replete with Lower Silurian life. Again, speaking of the close of the Silurian period, he says (p. 760): “There is every reason to believe that for a long time the marine sedimentation of Upper Silurian type continued to prevail in some areas, while the probably lacustrine type of the Old Red Sandstone had already been established in others.” He also tells us (p. 828) that “In the West of Scotland there occur among the red sandstones (some of which contain Old Red Sandstone fishes) bands of limestone full of true Carboniferous Limestone corals and brachiopods.” Again (p. 665), he draws our attention to the statement that “In Australia a flora with Jurassic affinities and a Carboniferous Limestone fauna were contemporaneous” while we may conclude our extracts by one which says: “At the present day the higher fauna of Australia is more nearly akin to that which flourished in Europe far back in Mesozoic time, than to the living fauna of any other region of the globe.”

On two occasions last year business took me to the north of Ireland, where I utilised my spare time by visiting the Giant's Causeway and the district adjoining. On the first occasion I went by rail from Londonderry to Portrush, an enjoyable ride, during which most interesting views were obtained of the Antrim chalk cliffs with their basaltic caps. This most characteristic feature of the coast line of N.E. Ulster was best seen at Downhill and Castlerock, while the great Atlantic breakers, from a recent storm, rushing shorewards and bursting in snowy whiteness on the sandy beach, presented a scene of beauty hardly surpassable. At Portrush we were transferred to the electric tramway car, having 8 miles still to go before reaching our destination. For the first 2 miles we skirt hills of blown sand, and then reach the exposure of strata known as the “White Rocks,” the equivalent of the English chalk, and overlaid by basalt which has burnt them nearly as hard as itself. These “White Rocks” form a continuous series of sea-cliff for some miles, and appear to be from 60 to 100 feet in height. The action of the sea has worn them into extraordinary shapes, and a Scotchman may here see in a couple of hours as many rock arches as he would in a lifetime in his own country. On a black cavernous rock, adjoining a fault which cuts off the chalk, stand the picturesque ruins of Dunluce Castle, with its narrow approach, and This 250-word extract was created in the absence of an abstract

The branch line connecting the College and Sighthill Stations of the North British Railway, was made principally to relieve the Queen Street terminus—long inadequate for the purpose—from the ever-increasing goods traffic. Although only about one mile and a half in length, its cost has been great, as besides heavy cuttings, with much building in and tunnelling, the Monkland Canal had to be diverted, and a new bed half a mile in length constructed. Minerals have been long and extensively worked in the district. I remember a deserted coal pit and a sandstone quarry where the Camlachie goods station now stands, while another pit was till lately visible near the Cumbernauld Road, about 100 yards north of Duke Street. Craigpark whinstone quarry and Blochairn sand quarry are still being worked. Although, owing to the thick overlying deposits of clay, the locality has been so barren to the geologist as not to have been mentioned in the Transactions of the Society except in one instance, and then only to state that nothing of interest was to be seen, yet I do not know any place, where, within the space of a mile, there can be seen more interesting geological features,—igneous and stratified rocks, boulder clay, and other glacial deposits, besides numerous fossil remains. Unfortunately a number of the sections have been built up, but of those hereafter described, parts at Burnbank, Blochairn, and Garngad Road are still visible. The first section worthy of note is one seen immediately after leaving the main

At the outset the author described in some detail the geographical aspect of the country. He then mentioned the temples and monuments which he had visited, particularly noting the rock-materials of which they were composed. Some of these buildings were entirely of alabaster, formed as a secondary deposit in the caverns which had been hollowed in the Tertiary limestone, while others were composed of the limestone or the granite of Assouan, or of the Nubian sandstone. He then gave an account of various geological phenomena observed by him. One group of beds on the opposite side of the Nile from Assouan seemed to be identical lithologically with our own Carboniferous rooks, with the Arran section of which they might be compared on account of the way in which they had been altered by the neighbouring granite. The general similarity was heightened by the occurrence of beds of ironstone and carbonaceous deposits, contained charred plant-remains. Another highly interesting section showed an intrusive boss of quartz surrounded by mica-schist. The occurrence of a large number of blocks of the petrified wood of an exogenous tree in the loose sand overlying the nummulitic limestone near Cairo was also described, while overlying the petrified forest was a bed of sand containing numerous beautifully-rounded water-worn pebbles, mostly of quartz. It was not easy to account for the origin of these pebbles, as the nearest rocks containing quartz, which Mr. Neilson had seen, lay something like 600 miles further south. On the surface of the desert This 250-word extract was created in the absence of an abstract