636 



SCIENCE. 



[N. S. Vol. XIV. No. 356. 



during Mesozoic and Tertiary periods, ac- 

 companied by a deepening of the river 

 channels ; the fourth was the early glacial 

 period, during which the elevation reached 

 its greatest development. The fifth period 

 was the post-glacial, characterized by sub- 

 sidence and partial submergence of the 

 land ; and the sixth and recent stage was a 

 stage of reelevation to the present condi- 

 tions, the process being accompanied by the 

 formation of raised beaches. 



On the mineralogical side papers were 

 read on ' The Copper- bearing Eocks of 

 South Australia,' by Mr. E. P. Manuell ; 

 on ' Scottish Ores of Copper in their Geo- 

 logical Eelation,' by Mr. J. G. Goodohild ; 

 on ' The Occurrence of Barium Sulphate 

 and Calcium Fluoride as Cementing Sub- 

 stances in the Elgin Trias,' by Dr. W. 

 Mackie ; and on ' The Source of the Allu- 

 vial Gold of the Kildonan Field, Suther- 

 land,' by Mr. Malcolm Maclaren, who took 

 occasion to advocate a return in certain 

 cases to the old theory of the precipitation 

 of gold from solution by carbonaceous mat- 

 ters, a theory which has been almost for- 

 gotten since Skey's demonstration of the 

 power possessed by sulphides to produce 

 complete precipitation. 



Of paleontological papers there may be 

 mentioned that by Professor Smith Wood- 

 ward on * The Bone Beds of Pikermi, At- 

 tica, and on Similar Deposits in Northern 

 Euboea,' giving an account of the excava- 

 tions made by the trustees of the British 

 Museum at the suggestion of Sir E. H. 

 Egerton, British Minister at Athens. 

 These researches have added but little to 

 the list of forms already known to occur in 

 the beds, though much important material 

 was obtained, and excavations at Achmet 

 Aga, northern Euboea, revealed bone beds 

 similar to those of Pikermi and containing 

 similar fossils. The most plausible expla- 

 nation of these bone deposits seems to be 

 that the bodies of animals were carried by 



torrential floods through tree-obstructed 

 water courses to lakes in which they col- 

 lected,, the broken limbs and torn fragments 

 of trunks affording evidence of the violence 

 of the passage to the lakes. Mr. J. L. 

 Beadnell of the Geological Survey of Egypt 

 gave a preliminary notice of the discovery 

 of a rich deposit of new Pliocene and post- 

 Pliocene fossils in the Fayum depression, 

 situated in the Libyan desert some fifty 

 miles southwest of Cairo, and Mr. B. N". 

 Peach presented a contribution to the Cam- 

 brian fossils of the northwest Highlands, in 

 which he pointed out that the fossils in the 

 Balnakiel group of the Durness dolomities 

 present a remarkable American facies and 

 suggested the existence in Cambrian times 

 of a large continent extending from the 

 north of Scotland to America, an idea 

 which, as was pointed out by Professor 

 Lapworth, was supported by the fact that 

 the succession of beds in northern Scotland 

 was paralleled only on the American conti- 

 nent. 



Professor Sollas described a method by 

 which serial sections, similar to those em- 

 ployed by zoologists, might be made of 

 fossils, and exhibited a machine designed 

 for the purpose by the Rev. G. Smith and 

 also showed wax models reconstructed from 

 serial sections of a Graptolite, of an Ophi- 

 uran and of Palceospondylus. 



Finally reference may be made to a sug- 

 gestive paper by Mr. J. R. Kilroe on ' Ge- 

 ology regarded in its Economic Application 

 to Agriculture by means of Soil Maps,' in 

 which he claimed that the geologist could 

 furnish much information regarding the 

 profitable localization of certain branches 

 of agriculture, such as stock-breeding, 

 dairying and tillage, and advocated the 

 publication of maps which would give in- 

 formation as to the nature of the soil in 

 different localities. The author believed 

 that much of practical value could be done 

 by the geologists even without an extensive 



