Oct. 13, 1887] 



NA TURE 



571 



lb 



The Antiseplic Properties of Mclallic Salts, by Prof. Cariielley. 



-This paper consisted of a description of experiments performed 

 by the author illustraiive of further relations between the 

 chemical composition of a substance and its antiseptic pro- 



erties. 



Antiseptic Properties of some Fluorine Compounds, by W. 

 homson. — The author describes in this paper the antiseptic 

 roperties of sodium fluosilicate. The body is not poisonous, 



and possesses no smell. Its superiority over chloride of mercury 



f^r surgical purposes is claimed. 



On the Composition of Water by Voltime, by A. Scott. — From 

 various preliminary experiments the author was led to conclude 

 that the relation of oxygen to hydrogen in water was not accu- 

 rately represented by the numbers i : 2. Subsequent experi- 

 ments gave the ratio i : i '997 with small variation. 



On some Vapour Densities at High Temperature, by A. Scott. 

 — A number of vapour densities of inorganic salts of certain 

 elements have been determined by means of the well-known 

 method of Victor Meyer, at a temperature above the melting- 

 point of cast iron. A breaking up of the molecule is shown to 

 occur in the case of iodine, cadmium iodide, mercuric sulphide, 

 mercuroas chloride, and mercuric chloride. 



On the Estimation of the Halogens and Sulphur in Organic 

 Compounds, by R. T. Plimpton. — The method suggested as a 

 substitute for those already in use is that of introducing the 

 substance into the flame of a Bunsen burner, or into a jet of 

 hydrogen, the products of the combustion being aspirated through 

 an absorbent liquid. In this solution the amount of the halogens 

 or of sulphur can afterwards be estimated. 



On the Derivatives and Constitution of the Pyrocresols, by W, 

 Bott and Prof. Schwarz. — The authors describe some derivatives 

 of these bodies, and are led to conclude that the a-pyrocresol 

 and its isomers are anhydrides similar in constitution to diphenyl 

 ether. 



Section C — Geology. 



On the Mineralogical Constitution of Calcareous Organisms, 

 by Vaughan Cornish and Percy F. Kendall. — In Dr. Sorby's 

 presidential address to the Geological Society in 1879 it was 

 stated that both calcite and aragonite occur in organic structures, 

 and that aragonite fossils are less stable than those of calcite. 

 It appeared probable that carbonic acid has been the agent 

 which effected the removal of the aragonite, but there are no 

 published experimental data to show that it would remove arago- 

 nite more readily than calcite. The authors gave an account of 

 the experimental evidence obtained as to the cause of the inferior 

 stability of aragonite fossils as compared with those formed of 

 calcite, with observations on the geological conditions favourable 

 to the removal of aragonite fossils. They then described the 

 work done in following out these observations, anil in the 

 examination of certain organisms belonging to groups not yet 

 classified according to their mineralogical constitution. 



The Matrix of the Diamond, by Prof. II. Carvill Lewis. — 

 A microscopical study of the remarkable porphyritic peridotite 

 which contains the diamonds in South Africa demonstrates 

 several interesting and peculiar features which are described in 

 detail. It is one of the most basic rocks known, and has a com- 

 position which by calculation would belong to a rock composed 

 of equal parts of olivine and serpentine, impregnated by calcite. 

 It is a volcanic breccia, but not an ash or tuff, the peculiar 

 structure being apparently due to successive paroxysmal eruptions. 

 A similar structure is known in meteorites, with which bodies this 

 rock has several analogies. The microscopical examination 

 supports the geological data in testifying to the igneous and 

 eruptive character of the peridotite, which lies in the neck or vent 

 of an old volcano. While belonging to the family of peridotites, 

 this rock is quite distinct in structure and composition from any 

 member of that group heretofore named. It is more basic than 

 the picrite porphyrites, and is not holocrystalline like dunite or 

 saxonite. It is clearly a new rock-type, worthy of a distinctive 

 name. The name Kimberlite, from the famous locality where 

 it was first observed, is therefore proposed. Kimberlite pro- 

 bably occurs in several places in Europe, certain garaetiferous ser- 

 pentines belonging here. It is already known at two places in ihe 

 United States : at Elliott County, Kentucky, and at Syracuse, 

 New York j at both of which places it is eruptive and post-Car- 



boniferous, similar in structure and composition to the Kimberley 

 rock. At the diamond localities in other parts of the world dia- 

 monds are found either in diluvial gravels or in conglomerates of 

 secondary origin, and the original matrix is difficult to discover. 

 Thus, in India and Brazil the diamonds lie in a conglomerate 

 with other pebbles, and their matrix has not been discovered. 

 Recent observations in Brazil have proved that it is a mistake to 

 suppose that diamonds occur in itacolumite, specimens suppo ed 

 to show this association being artificially manufactured. But at 

 other diamond localities, where the geology of the region is 

 better known than in India or Brazil, the matrix of the diamond 

 may be inferred with some degree of certainty. Thus, in Borneo, 

 diamonds and platinum occur only in those rivers which drain a 

 serpentine district, and in Timor Laut they also lie in serpen- 

 tine. In New South Wales, near each locality where diamonls 

 occur, serpentine also occurs, and is sometimes in contact with 

 carboniferous shales. Platinum, also derived from eruptive 

 serpentine, occurs here with the diamonds. In the Urals, 

 diamonds have been reported from four widely separated locali- 

 ties, and at each of these, as shown on Murchison's map, serpen- 

 tine occurs. At one of the localities the serpentine has been 

 shown to be an altered peridotite. A diamond has been found 

 in Bohemia in a sand containing pyropes, and these pyropes are 

 now known to have been derived from a serpentine altered from 

 a peridotite. In North Carolina a number of diamonds and some 

 platinum have been found in river sand-;, an I that State is 

 distinguished from all others in Eastern America by its great beds 

 of peridotite and its abundant serpentine. Finally, in Northern 

 California, where diamonds occur plentifully and are associated 

 with platinum, there are great outbursts of post-Carboniferous 

 eruptive serpentine, thi serpentine being more abundant than 

 elsewhere in North America. At all the localities mentioned 

 chromic and titanic iron-ore occur in the diamond-bearing sand, 

 and both of these minerals are characteristic constituents of ser- 

 pentine. All the facts thus far collected indicate serpentine, in 

 the form of a decomposed eruptive peridotite, as the original 

 matrix of the diamond. 



On the Discovery of Carboniferous Fossils in a Conglomerate 

 at Moughton Fell, near Settle, Yorkshire, by Robert Law and 

 James Horsfall. — After briefly noting the various exposures of 

 the conglomerate, its unconformability with the Silurian rocks, 

 its nature, probable age, and the circumstances which led to 

 the discovery of fossils in it ; the authors described the following 

 section exhibited on the south-west side of the Moughton Fell. 



Feet. 



a. Scar limestone, of light grey colour and 



well jointed ; layers very distinct in lower 

 parts and almost horizontal, the genus 

 Bellerophon being the commonest fossil 

 in the lowest bed of this rock ... ... 300 to 500 



b. Conglomerate. — Of a bluish-grey colour 



when newly fractured, and becoming red- 

 dish on exposure to the air. The frag- 

 ments consist of slate, grit, flagstone, and 

 vein-quartz, all apparently derived from 

 Silurian rocks. Fossil shells and corals 

 are common throughout the bed. Belle- 

 rophon, Euoinphalus, Syringopjra, and 

 Lithostrotion are the prevailing genera... i to 12 



c. Lower Silurian slates, of great thickness, 



having a north-east strike, and a dip of 

 about 65'. The dip and cleavage appear 

 to be on the same plane in this locality. 



The nature and the origin of the stones in the conglomerate 

 were next pointed out ; also it was shown that the portion of 

 the bed in which fossils had been found was not more than 200 

 yards in length, and that it was thickest in the middle, thinning 

 out to the east and west, and at one point could be seen merging 

 into the overlying limestone. Twenty species of fossils were 

 collected from the conglomerate. 



Places of Geological Interest on the Banks of the Saskatcheivan 

 by Prof. J. Hoyes Panton. — The writer, after referring to some 

 of the marked geological features which characterize the three 

 great prairie steppes of the North-west of Canada, proceeds 

 to describe two localities more particularly, viz. the vicinity of 

 Medicine Hat, situated on the banks of the Saskatchewan, 660 

 miles west of Winnipeg, and a locality near Irvine Station, 23 

 miles east of Medicine Hat. 



