Jan. 24, 1889] 



NATURE 



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Survey, opened the discussion, and regretted that, though 

 he had enjoyed the advantage of seeing the large collec- 

 tion of specimens made by the Duke of Argyll from the 

 Inveraray quartzite, and also of examining the rock in 

 situ, he was still unconvinced that the markings were 

 really of organic origin. It was possible, he thought, to 

 trace a Gcrics of stages from single crystals or irregular 

 groups of crystals of pyrites through variously shaped 

 aggregates into the " ovate bodies" of the Duke. In the 

 more solid, massive, and uncrushed portions of the quartz- 

 ite, these aggregates could be seen quite fresh, and 

 probably not far from their original shape. But wherever 

 the rock had undergone shearing (and this was the case 

 throughout most of its mass), its component particles 

 had been drawn out in the direction of movement, 

 the original irregular, rounded or egg-shaped aggre- 

 gates of sulphide of iron had been flattened and 

 elongated, becoming eventually mere strips that 

 run parallel to each other. The trend of these strips 

 exactly coincided with that of the long axes of the 

 foliation-minerals in the surrounding rocks, and were 

 regarded by Mr. Geikie as pointing to the results of 

 shearing in' the rock-mass and not to the burrowings of 

 worms. The ferruginous rings seemed to him to be due 

 to an oxidation and leaching out of the pyritous matter 

 of the little mineral aggregates, as so often happens 

 among the Carboniferous and Jurassic sandstones that 

 contain ferruginous concretions. While he could not 

 admit that the markings in the quartzite of Inveraray had 

 yet been shown to be of organic origin, he thought it 

 quite possible that the precipitation of the iron-disulphide 

 had originally taken place in presence of decomposing 

 organic matter, as in many blue muds of the present day, 

 and that portions of such pyritous mud had been drifted 

 into the sandy deposit which is now quartzite. 



Mr. B. N. Peach, of the Geological Survey, was also 

 unable to recognize organic forms among the Inveraray 

 markings. He thought that the parallelism of these 

 markings where they were most elongated, and their 

 coincidence with the general line of shearing movement 

 in the rock, cast doubt upon their having any connection 

 with worm-burrows. 



Mr. Murray, of the Challenger Expedition, who thinks 

 that sandstone deposits generally are sub-aerial forma- 

 tions, was disposed to refer the so-called annelid tubes 

 of the Sutherland quartzite not to the borings of marine 

 worms, but to the remains of terrestrial plants that grew 

 upon sand-dunes. 



In a paper which followed this discussion, Mr. Geikie 

 gave an account of the evidence supplied by the rocks of 

 the Highlands of remarkable deformation by mechanical 

 movements. Illustrating his remarks by a large series of 

 specimens, he showed how the Cambrian conglomerate of 

 Assynt had its pebbles of quartz drawn out and its original 

 sandy mud converted into a fine micaceous schist ; 

 how the conglomerates of the Central Highlands had 

 their quartz-pebbles flattened like buttons and drawn out 

 in the direction of movement, while their envelope of 

 original sand and mud had been changed into a quartz- 

 schist ; how the granular quartzite of Sutherland had been 

 crushed and rolled out into a thoroughly schistose mass ; 

 how the coarse Archaean pegmatites had been likewise 

 crushed down until their material had, as it were, flowed 

 onwards so as now to show a close parallel to the " fluxion- 

 structure " of many porphyries, and even to assume a finely 

 laminated or shaly structure,'and lastly, howthe highly crys- 

 talline basic dykes of the most ancient gneiss of the north- 

 west had been sheared and rearranged until they passed 

 into the most perfect forms of sericite-schist. He adverted 

 to the obviously sedimentary origin of the great mass of 

 the rocks constituting the Highlands east of the line of 

 the Great Glen, and mentioned that the recent work of 

 the Geological Survey in tracing the great belt of lime- 

 stones from the coast of Banffshire through the Grampians 



into Argyllshire afforded now a good horizon, from which 

 it might be hoped the general structure of the Highlands 

 might be worked out. He exhibited specimens of quartzite 

 from Perthshire and other districts containing various 

 markings, some of which there could be little doubt were 

 of organic origin. He also showed a singularly interest- 

 ing series of specimens which he had recently received 

 from Dr. Reusch, of the Geological Survey of Norway, 

 displaying recognizable trilobites and corals embedded in 

 a finely crumpled micaceous schist, exactly similar in 

 character to much of the schist that constitutes wide 

 regions in the Scottish Highlands. These specimens 

 afforded much encouragement to search for fossils in the 

 calcareous«and ferruginous layers and concretions that 

 occur so frequently among our finer mica-schists and 

 phyllites. 



THE LA W OF STORMS IN CHINA. 



THE law of storms in Hong Kong was investigated by 

 aid of the lithographed paths of the typhoons in 

 1884 and 1885, published in "Observations and Re- 

 searches made in 1886" and in those of i885 and 1887 

 now in course of publication. Only those within 300 

 miles of the Obseirvatory were considered in this connec- 

 tion. The angles between the wind and the radius vector, 

 i.e. the line joining the Observatory with the centre of the 

 typhoon, were measured and mean values derived, and the 

 same was done for Victoria Peak (1816 feet above the sea) 

 and for the lower clouds. 



No connection could in any case be traced between the 

 distance from the centre and the direction of the wind, 

 but the latter depends upon the bearing of the centre. As 

 pointed out in " The Law of Storms in the Eastern Seas " 

 (Nature, vol. xxxv. p. 136), and elsewhere, the wind has 

 a tendency to blow along the southern coast of China 

 when a typhoon is raging in the China Sea, so that the 

 wind in such cases veers only about half as much while 

 the typhoon moves westward as in other cases, and this is 

 the reason why the angle between the wind and the radius 

 vector is larger than usual when the centre is situated to 

 the south of Hong Kong. 



When there is a typhoon anywhere between north and 

 east within 300 miles of the colony— which, however, is 

 not common— the wind at the Peak (about north-north- 

 west) blows away from the centre — much more so than 

 the clouds, which in fact describe almost a circle round 

 the centre in that case ; and this remarkable feature or 

 something very like it has been found to obtain also at 

 Ben Nevis with the centre of a depression in the north-e ist. 



The angle between the wind and the radius vector is, at 

 the Observatory, 8i° north of the centre, 55^ to the west, 

 56° to the south, and 58° to the east. At the Peak, it is 

 91° to the north, 87° to the west, 81° to the south, and 78° 

 to the east. At the level of the lower clouds, it is 92' to 

 the north, 85° to the west, 67° to the south, and 86° to 

 the east. 



The observations made at South Cape (Formosa) were 

 treated similarly, with the following result : to the north 

 of the centre the angle was 50°, to the west 56°, to the 

 south 64°, and to the east 47^". 



The angle observed on board ship in the China Sea in 

 typhoons— say in about 16^ N, lat.— is on an average 

 47^, as previously published ; at South Cape (22° N. 

 lat., the same as Hong Kong) 54^ ; at Hong Kong 62" ; 

 at Victoria Peak, above Hong Kong, 84'' ; and at the level 

 of the lower clouds 82^. The angle previously obtained 

 from observations made on board ship, and also at coast 

 stations in about 32" N. lat, was 75^ on an average, 

 but so far north it seems to be more variable than in the 

 China Sea, where it has been found remarkably constant, 

 between (say) 12° N. and 20"* N. But from the figures given 

 it is seen that the angle increases with the latitude and 

 with elevation above sea-level. The woodcut represents 

 a typhoon in the neighbourhood of Hong Kong, or rather 



