430 | Brief Notices. 
series or the Washington formation of the Dunkard group of the 
Permian series. 
V.—Brier Noricss. 
1. Tue Georoeican Structure oF THE Soura Lancasuire Coat- 
FIELD.—In a paper read before the Manchester Geological Society 
and published by the Institute of Mining Engineers (Trans. Inst. 
Mining Eng., vol. 1, pt. 11, pp. 328-50), Dr. Hickling discusses the 
general structure of the South Lancashire coalfield, with special 
reference to the possible occurrence of coal at workable depths below 
the Permian and Triassic rocks. It is shown that the structure of 
the coal-basin is remarkably complex, owing to the large number of 
folds and faults which traverse it. By much patient work this 
structure has been to a large extent unravelled, and the very important 
conclusion is reached that a large area of Middle Coal-measures exists 
to the south and south-west of Manchester, under a cover of Permian 
and Triassic rocks, which in all probability is not too thick to prevent 
profitable working. This should lead to important developments in 
the not far distant future. A second paper by the same author read 
at the same meeting deals with a small inlier of Lower Coal-measures 
in Croxteth Park. The result of trial borings was disappointing, as 
there was no workable coal. 
2. Tunesten Ores.—In a paper read before the Chamber of Mines 
of the Federated Malay States in March last Mr. J. B. Scrivenor 
gives an account of the occurrences and production of tungsten ores 
in that region. The tungsten occurs in association with tin ores, 
chiefly as wolframite, with some scheelite. The wolframite is 
separated from the tin ores by magnetic processes, but scheelite is 
non-magnetic and some loss occurs in this way. Unfortunately the 
outputs are stated only in local weights, pikuls, which convey 
nothing to the ordinary reader. As to the genesis of the ores, it is 
clear that they are products of pneumatolytic modifications of granite, 
and in the case of the scheelite of limestones. There seems to be 
every reason to believe in the possibility of a largely increased output 
of these ores, which are now in great demand owing to the War. 
3. Sprcrat Reports on THE MineRaL Resources or Great Briain. 
(Memoirs of the Geological Survey.)—The fourth volume of this 
useful series is devoted to Fluorspar. This mineral has become of 
considerable importance of late years as a flux in the metallurgy of 
iron, and large quantities are exported from Britain to the United 
States. Hitherto the chief source of supply has been the waste-heaps 
of lead-mines in Derbyshire and Durham, but these are becoming 
exhausted, and the question now arises to what extent it would be 
profitable to mine fluor-spar for its own sake. In this memoir 
descriptions are given of every known occurrence in this country. 
There would appear to be a possibility of considerable future 
development. At the present time it is of special importance that | 
a search should be made for fluor-spar of sufficiently good quality for 
optical purposes, which is now exceedingly scarce and commands 
a very high price. The fifth volume contains an account of the 
production in the British Isles of the following useful minerals: 
