590 



KNOWLEDGE & SCIENTIFIC NEWS. 



[XOVEMBER, Jl,o6. 



ammonia, ami 0.22 grain of albuminoid ammonia. It was 

 stronjjly saline, tlie chief salts present bcinp; ortlinary salt 

 and maijnoiiini sulphate. Sir Richard Burton commented 

 upon its extriine bitterness, and ijave a humorous account 

 of his attempts to make his fello\v-pil£jrims drink more of 



Tin flask of Zem-Zem Water brought from Mecca in 1854 by Sir 

 Richard Burton.— Four-tifths of actual size. 



their dose of Epsom salts, while he " mocked at their scanty 

 .-Hid irreverent potations." The water has evidently altered 

 but little in its general characteristics of foulness during 

 the last half century, and must still be regarded as per- 

 manently dangerous' in itself, apart from the share it has 

 been known to have from time to time in spreading diseases 

 such as cholera. 



Volcanic Ash from Vesuvius. 



Specimens of the substances thrown up by Vesuvius 

 during the last great eruption in .April of this year have 

 been examined by .M. Cosyns, of Brussels. The ash was 

 remarkable for the small amount of moisture it contained — 

 only 0.28 per cent. On treatment with water it yielded 1.68 

 per cent, of soluble substances, consisting principally of 

 calcium sulphate and sodium chloride. Roughly speaking, 

 the ash was composed, in the main, of 50 per cent, of augite 

 (a silicate in which iron and calcium predominate), 40 per 

 cent, of biotite (a silicate containing aluminium and 

 magnesmm), and 10 per cent, of leucite (sodium potassium 

 and aluminium silicate), magnetite, S:c. There was a dis- 

 tinct difference in the characteristics of the ash which fell 

 on -April 4 and 5, and of that which fell on the 14th, the 

 former containing much more moisture and a larger pro- 

 portion of vitreous fragments. On extraction with ether 

 the ash yielded a small amount of a combustible organic 

 matter, which distilled at a high temperature, had a tarry 

 odour, and became brown on exposure to the air. It was 

 found to be a hydrocarbon, and was evidently identical with 

 the substance vvhich Silvestri discovered m the ash from a 

 previous eruption, and termed "vaseline." Similar hydro- 

 carbons have been found in the ash from other volcanoes, 

 and -M. Cosvns considers that volcanic activity is more or 

 less closely connected with chemical reactions that lead to 

 the formation of hydrogen and hydrocarbons, often in con- 

 siderable quantity.' Notable instances in support of this 



view occur in the volcanic regions of the .Apennines, where 

 the combustible gases carry bitumen and petroleum to the 

 surface of the soil ; in the petroleum wells in the volcanic 

 districts of Baku ; and in certain springs of petroleum in 

 Canada, which issue from a volcanic rock containing nodules 

 of extremely radio-aelive bituminous carbon. 



A Chemical Test for Mould Fungi. 



The action of certain mould-fungi upon cinnamic acid 

 has been utilised by M. Oliviero as a means of detecting 

 their presence. Cinnamic acid, which is closely related to 

 benzoic acid, occurs naturally in balsam of Tolu and in 

 storax, and can be prepared from these resinous compounds 

 in the form of fine feathery crystals. It can also be pre- 

 pared synthetically from oil of bitter almonds. When dis- 

 tilled with an excess of lime it yields cinnamene, CgH^, a 

 liquid hydrocarbon with a very ch.aracteristic fragrant 

 odour. The reduction of cinnamic acid to cinnamene is also 

 effected by a ferment (enzyme) secreted by certain mould- 

 fungi, notably Axperqillu.i niqer, PeniciUium rjlauCAim, and 

 probably others. Thus when a well-dcvelojied culture ct 

 A. niqcr is thoroughly shaken and filtered through porous 

 porcelain, and the sterile filtrate brought into contact with a 

 weak solution of the sodium salt of cinnamic acid, the un- 

 mistakable odour of cinnamene at once becomes apparent. 

 .So sensitive is the reaction that cinnamic acid mav be used 

 as a test for the moulds which sometimes form in medicinal 

 preparations that have been stored for some time. It also 

 throws light upon the occasional rapid deterioration of 

 pharmaceutical products, such as balsam of Tolu, which 

 contain cinnamic acid. 



GEOLOGICAL. 



By Edward A. Martin, F.G.S. 

 The Sand-hills of the River Bush 



The illustration shows an excavation formed by marine 

 action in the sand-hills, which are now found at the mouth 

 of the river Bush, on the northern coast of Antrim, the 

 town of Bushmills being about a mile up the river. 

 Probably at one time the embouchure of the river extended 

 the whole of the way as far as the town, with a width ex- 

 tending from near the Giant's Causeway across to the 

 headland at Port Ballintrae. The present meanderings of 



Sand-hitls and Ba.vlet at Mcutti of River Bush. 



the river here are not, as is so often the case, the result of 

 silting-up, but rather through the advance of sand-dunes 

 blown inland from the ever-plentiful supply of sand forming 

 along the coast. These low hills are devoid of consolida- 

 tion, but are held together in some places by thick growths 

 of grass. In the photograph a baylet has been formed, and 

 this has been strewn with rounded blocks of basalt, from the 

 disintegration of which the material of the hills has been 

 derived. 



