22 



NA TV RE 



[July i, 1922 



Panay, Cebu, and Leyte ; those of the Cotabato 

 district in Mindanao, in particular the Pidatan seepage, 

 are of more recent discovery, Pidatan not receiving 

 detailed geological attention until the expedition 

 of 1921, of which this paper is a report. The Pidatan 

 field is' about 60 kilometres north of Fort Pikit, 

 Cotabato Province, the basin of the Rio Grande de 

 Cotabato, practically in the centre of the island. The 

 topography is mountainous and the country is exceed- 

 ingly difficult. Geologically, the formations present 

 consist principally of Tertiary limestones, sandstones, 

 and shales pierced by basaltic and andesitic intrusions. 

 The sediments are of recent, Pleistocene, Pliocene, 

 and Miocene ages, many horizons yielding fossil 

 evidence. The structures, however, appear to be 

 very complex, owing to the regional earth movements 

 and the igneous activity manifested. In fact, the 

 faulting and folding has so disturbed the oilfield 

 region that Dr. Smith does not hesitate to condemn 

 the area from the economic point of view. On the 

 other hand, the presence of the seepage and the nature 

 of the oil involved at Pidatan suggest that petroleum 

 certainly occurs 111 central Mindanao, possibly over 

 an extensive region, and the advisability of intensive 

 geological exploration over a wider area is clearly 

 indicated. Analysis of the oil from the occurrence 

 at Pidatan shows that it has a specific gravity of 

 0-9297 and is of paraffin base ; no light fraction was 

 obtained (under 150 C), kerosene and heavy, oil 

 representing 45 per cent, and 49-5 per cent, of the 

 sample respectively (by volume). Results of other 

 tests indicate that the oil is much inspissated, as would 

 be expected considering the geological circumstani es, 

 and is most suitable for use as a Diesel engine fuel. 

 The author concludes his paper with a commendable 

 caution to those controlling oil companies against 

 belittling the value of sound geological woik as a 

 necessary preliminary to oil exploration ; while not 

 detracting from the value of the " practical " man's 

 work, he makes it quite clear that success is achieved 

 only where both driller and geologist work in harmony, 

 a conclusion deserving of serious consideration by many 

 of the would-be " wild-cat " oil explorers in our own 

 colonies. 



The Geology of the Mount Everest District. — 

 The Mount Everest expedition of last year included 

 among its slaif Dr. A. M. Heron, who contributes to 

 the Geographical Journal of June an account of his 

 geological investigations, accompanied by a geological 

 map. The mapping is virtually a westward continua- 

 tion of Sir H. Havden's investigations during the 

 Tibet Expedition of 1903-4. Dr. Heron's task was 

 one of unusual difficulty. Over much of the area 

 examined his work had" to proceed in advance oi 

 surveys, while the movements of the expedition 

 were generally unfavourable to detailed work. Close 

 and prolonged examination, moreover, was considered 

 inadvisable, since it aroused the suspicions of the 

 Tibetans. Dr. Heron claims that his work must be 

 looked on only as a reconnaissance. The area 

 examined covers more than 8000 square miles, and con- 

 sists in the main of the Tibetan portion of the drainage 

 area of the Aran river above Kharta. Two geological 

 divisions can be recognised : a Tibetan area of 

 sedimentary rocks which consists chiefly of east and 

 west folds of Jurassic slates, and the crystalline 

 Himalayan region to the south. The contrasts 111 

 topography clearly illustrate the differences in the 

 underlying structure. On one hand are the somewhat 

 tame rounded ranges, with broad valleys, of Tibet, 

 and on the other the high, steep, and rugged 

 Himalayas. 



Recovery of Sugar from Beet Molasses. — Beet 

 molasses is a substance of almost constant composi- 



NO. 2748, VOL. I IO] 



tion, containing 50 per cent, of sugar, 10 per cent, 

 of ash, 15 per cent, of other organic substances, 

 and 25 per cent, of water. The sugar cannot be 

 separated from it by direct means, and among the 

 methods employed for recovering the sugar is 

 precipitation by one of the alkali earths. Until 

 the present lime and strontia have chiefly been used. 

 In the year 1838, however, Peligot found that 

 baryta forms a very sparingly soluble saccharate. 

 The use of baryta for the purpose of separating sugar 

 was never carried out to any great extent for two 

 reasons ; (a) its cost, and (6) the poisonous nature 

 of barium compounds. The cost of baryta should 

 now be considerably reduced by the discovery of 

 two French chemists, MM. Camille Deguide and 

 Paul Baud (Comptes rendus, May 1). who find that 

 when barium carbonate is heated with silica at a 

 temperature of i5o°-2oo° C, and the mixture sub- 

 sequently lixiviated with water, the carbonate is to 

 the extent of more than 90 per cent, converted into 

 hydroxide. This process should therefore render 

 baryta available for the desaccharification of molasses. 

 It is, however, very doubtful whether any Govern- 

 ment will permit its use on account of the toxic 

 character of traces of barium compounds. 



Pyrex Glass. — The Chemiker Zeitung of May 25 

 contains an analysis of the " Pyrex glass " manu- 

 factured in America and used for cooking vessels. 

 This glass is an astonishing resistant to changes of 

 temperature, and may be used over an open fire. 

 The chemical composition was found to be, in per- 

 centages : silica, 8071 ; boric anhydride (B,0 3 ), 

 10-47 •' alumina, 3-55 ; lime, 0-70 ; magnesia, 0-57 ; 

 soda (Na 2 0), 4-14. The low alkali content is note- 

 worthy. Experiments showed that ordinary heating 

 is not sufficient to melt the materials for such a glass, 

 and special furnaces, possibly with surface-combustion 

 heating, are assumed. 



Safety Devices in Wireless Equipment. — The 

 American Bureau of Standards has given its approval 

 to the recommendations of a committee of the 

 National Fire Protection Association proposing the 

 addition of some new safety rules to the National 

 Electric Code relating to wireless telegraph installa- 

 tions. The proposed regulations provide for the 

 protection of receiving and transmitting equipment 

 against lightning effects, avoidance of risk of contact 

 with neighbouring electric light and power circuits, 

 and protection from effects of high potential surges in 

 the lines supplying power to the equipment, as well 

 as the ordinary requirements of sound construction. 

 Tt is needless to detail all the proposals, but it may be 

 remarked that, in the case of receiving equipments, 

 a lightning arrester is required where the leading-in 

 wire enters a building and, on account of the larger 

 size of the ordinary transmitting aerial, which is 

 more likely to be subject to damage from lightning, 

 and the high voltages produced in the apparatus, the 

 provision is recommended in transmitting stations 

 of a double - throw switch for connecting the aerial 

 either to the transmitting apparatus or to earth. The 

 use of this switch makes it possible to disconnect 

 the aerial entirely from the transmitting apparatus. 

 On account also of the difficulty which has been 

 experienced by the induction of voltages in the 

 supply lines of a transmitting station, it is advisable 

 to use a protective device across the power line near 

 its point of entrance. It is noticeable that copper- 

 clad steel wire is recommended throughout as an 

 alternative to copper wire, owing to the fact that these 

 two kinds of wire are practically equivalent in their 

 conductivity for high - frequency current, while the 

 former is stronger mechanically. 



