December 26, 1907J 



NA TURE 



Dr. C. M. Luxmoore has sent us a copy of his final re- 

 port on the analysis of one hundred soils from the county 

 of Dorset, preliminary reports upon which, by Dr. Lux- 

 moore himself and by Prof. Percival, have already been 

 issued from the University College of Reading. The soils 

 and their subsoils have been taken from typical localities 

 situated upon all the formations, ranging from the Bagshot 

 Sands to the Lower Lias, which are exposed in the county, 

 and the report contains detailed analyses, both mechanical 

 and chemical, together with certain determinations of their 

 physical constants. In this latter connection one or two 

 novel methods of examination have been proposed, de- 

 signed to obtain some information as to the behaviour of 

 the soils in the field. In addition to the analytical figures, 

 the report contains a full discussion of the results, in 

 which attempts are made to estimate the interdependence 

 of some of the constituents and the extent to which they 

 may be correlated with the properties of the soil. The 

 report represents a very considerable piece of work, which 

 has occupied Dr. Luxmoore for many years. 



In N.4TDRE of December 27, igo6 (vol. Ixxv., p. 197), 

 attention was directed to the remarkable book by Dr. F. 

 Oswald on the " Geology of Armenia." A second edition 

 of this work is now promised ; and the author has issued 

 a large lithographed map of the country described, on 

 which the geological features are coloured by hand. This 

 map and an explanatory pamphlet are published by Messrs. 

 Dulau and Co., London (25s. net), and should obviously 

 be secured by those libraries that possess the original work 

 of reference. The country dealt with includes, as a central 

 feature, the great lacustrine and volcanic plain north of 

 Lake Van, and its extent may be judged from the fact 

 that the scale of the map is i inch to sixteen miles, and 

 that the sheet measures 37J inches by 213 inches. In the 

 pamphlet, w-hich is in itself a guide to the geological 

 structure of .Armenia, the striking extent of the marine 

 transgression in early Miocene times is emphasised, the 

 present country being due to Middle Miocene folding, 

 followed by fault-block movements during the Pliocene 

 period. 



The annual report of the State geologist of New Jersey 

 for igo6 (Trenton, 1907) is a volume of 192 pages, con- 

 taining, in addition to the administrative report for the 

 year, valuable papers on building stones, on the glass- 

 sand industry, on the Triassic copper ores, and on trap 

 rocks for road construction. Mr. W. E. McCourt has 

 made some careful tests to determine the fire-resisting 

 qualities of New Jersey building stones. The crystalline 

 rocks at a temperature of 550° C. were not greatly 

 affected. The gneisses cracked parallel to the banding, 

 and, as a rule, it is safe to assume that a gneiss will 

 be more damaged than a crystalline rock of the same 

 texture and composition without the banding. Clay rocks 

 suffered badly. The sandstones resisted fairly well, while 

 the limestones seem to have suffered the least injury of 

 all the stones tested. The paper by Messrs. H. B. Kiimmel 

 and R. B. Gage on the glass-sands of New Jersey shows 

 I hat they contain more iron, and consequently obtain lower 

 priri/s at the glass factories than do the Pennsylvania 

 sands with which they compete. If the iron-bearing 

 minerals could be removed by improved methods of wash- 

 ing, by magnetic separation, or by sieving, a grade of 

 glass-sand superior to the best Pennsylvania sand would 

 be obtained. Mr. J. Volney Lewis gives the results of 

 his investigations of the ■ petrography of the trap rocks 

 and of the origin of the copper ores commonly found in 

 proximity to them. The view put forward that the copper 

 NO. 1 99 I. VOL. 'J1~\ 



ores are deposits from ascending magmatic waters expelled 

 from the great intrusive mass in the vicinity appears to be 

 well supported by facts. Lastly, a record is given of tests 

 of the resisting qualities of the trap as determined by a 

 series of experiments carried out in cooperation with the 

 Department of Agriculture. As the trap rocks are 

 extensively used for road metal, these tests of their wear- 

 ing qualities should prove of value when considered with 

 regard to the results already shown by actual use. 



A COLOURED supplement to the December number of the 

 Quarry conveys an admirable impression of the appearance 

 of the green marble now being quarried on the island of 

 lona. The marble occurs in gneiss of pre-Cambrian age 

 as a well-defined vein, and its beautiful green colour is due 

 to the presence of serpentine derived from forsterite by 

 hydration. 



.An important contribution to the study of weathering 

 phenomena in building stones is afforded by a paper by 

 Mr. E. Kaiser on the Stuben sandstone of Wurttemberg 

 in the Neues Jahrbuch fiir Mineralogie (1907, ii., pp. 

 42-64). This stone was largely used in 1842 to 1868 on 

 Cologne Cathedral, and now exhibits marked disintegra- 

 tion, the weathered material showing an external layer of 

 scale, and below it a layer of soluble calcium and mag- 

 nesium sulphates. In the quarry, on the other hand, the 

 weathering consists in solution of the calcium and mag- 

 nesium constituents of the brown spar in the rock with 

 deposition of the iron as hydrated ferric oxide. It is 

 evident that the disintegration in Cologne is caused by 

 sulphur derived from smoke gases. 



A DET.11LED account has been published by Mr. N. W. 

 Lord (United States Geological Survey, Bulletin No. 323) 

 of the experimental work conducted in the chemical labora- 

 tory of the United States fuel-testing plant, St. Louis, 

 between January i, 1905, and July 31, 1906. Interesting 

 results have been obtained in the determinations of specific 

 gravities of coal, in laboratory methods of determining the 

 adaptability of coals to improvement by washing, and in 

 the estimation of volatile matter in coals and lignites. It 

 is shown that the value obtained for volatile matter in coal 

 is affected by the method of heating the sample, by the 

 fineness .of pulverisation, and by the amount of loosely 

 held mni^luro nr-^erit. 



The question of the concentration of ores is one to 

 which much attention has recently been devoted, and in- 

 ventors have been busy in the new field of flotation pro- 

 cesses in which the concentrate is removed from the top 

 and the tailings from the bottom, apparently in contraven- 

 tion of the law of gravity. A new process invented by 

 Mr. A. P. Macquisten, and successfully applied in the 

 United States, is described in the Engineer of December 13. 

 It is based on the utilisation of the surface tension of 

 liquids, it having been found that sulphide ores possess 

 some property that prevents them from becoming wetted, 

 whilst gangue minerals do not possess this property, and 

 readily sink. .At the Adelaide mine, Nevada, the process 

 has been applied to copper pyrites, iron pyrites, blende, 

 and galena with heavy gangue minerals, the presence of 

 which rendered ordinary methods of concentration in- 

 effective. 



We have received from Dr. Van Rijckevorsel parts iii. 

 and iv. of his laborious investigation entitled- " Constantly 

 Recurring Secondary Maxima and Minima in the Yearly 

 Range of Meteorological Phenomena." For details as to 

 the methods employed we would refer our readers to the 



