202 



NATURE 



[May 4, 1916 



a whizzing noise, rather like the explosive bombs. 

 They blazed furiously, and lit up the whole neighbour- 

 hood. We had, however, no great difficulty in extin- 

 guishing one with a hand fire-extinguisher. They 

 contain, I imagine, tar, petrol, and much besides. 



The rapid succession of the bombs and the spacing 

 apart of the holes showed that the Zeppelin was 

 travelling at high speed at the time, due no doubt to 

 the activity of the anti-aircraft guns. She could not 

 have hoped to hit any specific object, and, indeed, 

 ludicrously failed to hit anything but clay. 



The control of the airship was considerable. She 

 was very nimble in endeavouring to evade the search- 

 lights, which, however, had no difficulty whatever 

 in keeping her in the beam. 



Observer. 



THE KIMMERIDGE OIL-SHALES. 

 "T^HE rapid extension of the use of oil fuel in the 

 J- Navy, coupled with the desirability, for ob- 

 vious reasons, of securing adequate supplies from 

 home sources, has led to renewed attention being 

 given to the large and easily accessible deposits of 

 oil-bearing shales which have long been known to 

 occur in the vicinity of Kimmeridge, in Dorset- 

 shire, and there is reason to believe that the 

 question of their immediate utilisation has already 

 been urgently pressed upon the notice of the 

 Admiralty. 



Assuming that oil of a satisfactory character 

 can be obtained from these shales, there are 

 several considerations which would seem to point 

 to Kimmeridge itself, or some place in its near 

 vicinity, as a suitable spot at which to establish 

 workings, not the least important of which is its 

 proximity to Portland, one of our leading naval 

 stations. Kimmeridge is close to the coast, and 

 although somewhat exposed to gales from the 

 south-west, might be made sufficiently secure as 

 a harbour to enable shipments of the shale to be 

 made to Castletown, or other convenient locality, 

 if it were found impracticable to distil the shale 

 near the place where it is raised. And in any 

 case, should difficulties be found in making the 

 Kimmeridge haven sufficiently safe for vessels to 

 lie at anchor or alongside the jetty that would 

 have to be constructed, Portland Harbour of 

 Refuge is only a few miles distant, and can 

 be entered at any time of tide, and in any weather. 



Many attempts have 1>een made to work the 

 Kimmeridge shales for oil, but hitherto without 

 much success, owing largely to the character of 

 the product and the difficulty of rectifying it into 

 a marketable product as naphtha and illuminating 

 oil. But the nature of oil fuel is wholly dis- 

 similar from that of ordinary burning oil, and its 

 chemical and physical characters are quite 

 different. Nor is the same standard of quality 

 as regards colour, freedom from sulphur, etc., 

 needed in a fuel oil as in an oil intended for 

 illuminating purposes. Hence it is possible that 

 there may be an outlet for the Kimmeridge oil 

 that has hitherto been denied it. 



The Kimmeridge shales have long received the 

 attention of geologists, and their extent and dis- 

 tribution have been carefully traced. The outcrop 

 along the Dorsetshire coast begins a mile or two 



NO. 2427, VOL. 97] 



to the west of St. Alban's Head, and, as see 

 from the sea, forms a very striking natural featui 

 as Kimmeridge is approached. The deposil 

 extend to very considerable distances, and are c 

 unknown depth. To the west they are found z 

 Portland, which^ indeed, is known to rest upo 

 them, and they were formerly worked for fuel i 

 the island. They come out here and there aloa 

 the West Bay, or in its vicinity, as far as Abbotj 

 bury. They have been known in times past t 

 ignite spontaneously, probably owing to the hea 

 developed by the rapid oxidation of marcasite 

 or some other form of iron pyrites. They exten 

 to the north of Dorsetshire, and have been trace 

 by borings and by outcrops in a north-easterl 

 direction to Norfolk, and through Lincolnshir 

 to the Humber. 



In the neighbourhood of Kimmeridge the shal 

 was long used as fuel, and is still so used to ; 

 limited extent in the country cottages. In the six 

 teenth and seventeenth centuries it was worke( 

 for alum as at Whitby, and by the same methods 

 the large quantity of pyrites it contains affording 

 the sulphuric acid, whilst other portions servec 

 as fuel for evaporation, etc. 



The shale seems to have been first worked foi 

 oil about 1848, when small shipments were sent 

 to Weymouth, where the retorting was done — a 

 fact which was held, although unsuccessfully, tc 

 invalidate Young's patent for the manufacture, of 

 paraflfin oil by destructive distillation at a low 

 temperature. At the famous trial Vice-Chan- 

 cellor Stuart ruled that "the manufacture of 

 offensively-smelling and unmarketable oils from 

 Kimmeridge shales could not be held to be an 

 anticipation of Young's patent." It is, however, 

 interesting to note that Weymouth was the first' 

 place in the United Kingdom at which the di 

 filiation of shale for the production of hydr^ 

 carbon oils was attempted on a manufacturin 

 scale. 



In addition to oils of various grades the shah 

 yield notable quantities of ammonia on distill; 

 tion, a fact which has an important bearing upo 

 their commercial value. 



In a highly interesting and suggestive pape 

 recently read to the Institution of Petroleur 

 Technologists, Mr. W. Hardy Manfield has give 

 a very full account of the Kimmeridge oil-shale.^ 

 their distribution and geological features, and c 

 the various attempts which have been made t, 

 turn them to account. The communication als 

 gives a description of the method? of winning 

 oil-shale, of distilling it, and of treating the pn; 

 ducts, based upon practical experience. Tl: 

 paper is particularly valuable on account of tfj 

 author's local knowledge of the Kimmeridg, 

 deposits. 



The great objection to the use of Kimmerid^; 

 oil is due to the large quantity of sulphur it co:i 

 tains, which it has hitherto been practically ifi 

 possible to remove to a suflficient extent to mal, 

 the oil marketable. All attempts at purificatif. 

 by the methods of treatment ordinarily usedi 

 mainly acid and alkali — are of little value. T 



