December, 1906.] 



KNOWLEDGE & SCIENTIFIC NEWS. 



615 



condition as at first, after constant exposure for 27 months 

 to the action of smoke, while the sticUy layer of paint on 

 tlie metal was also intact, and in some places still not dry. 

 It was also proved that steel treated in this way could 

 remain in contact with moist air and sewer gases without 

 its surface being- in any way attacked. 



The Amount of Alcohol in Bread. 



The fact that, in the priiccss of leavciiini;-. Hour is made 

 to undergo a restricted fermentation, suggests the pro- 

 bability that the finished loaf may retain a small amount of 

 alcohol which has not been expelled by the heat of the oven. 

 This supposition was confirmed by Herr Balas, who found 

 that freshly-baked English bread contained from 0.2 to 0.4 

 per cent, of absolute alcohol. His assertion has recently 

 been investigated by Herr Pohl, who has distilled large 

 quantities of two kinds of German wheat bread with water, 

 and examined the distillates. In every instance he has 

 detected alcohol, though in smaller quantities than those 

 found by Hetr Balas, the proportions ranging from 0.05 to 

 o.oS per cent. In addition to alcohol, the distillates also 

 invariably contained a small amount of a dark brown oil 

 with the distinctive odour of new brrnd. 



The Occurrence of Copper in Olive Oil. 



Signor Passerini has analysed 28 specimens of olive 

 oil of different origin and finds that copper is present as a 

 normal constituent, though only in the small proportion of 

 about 0.005 pEirts in 1,000. .Some of the olive trees had 

 been treated with a one per cent, solution of copper sul- 

 phate, but this had not increased the quantity of copper in 

 the oil expressed from the fruit of those trees. This 

 minute trace of copper in (he oil is obviously too insignifi- 

 cant to have importance from a hygienic point of view. 



GEOLOGICAL. 



By Edwakd a. Martin, F.G.S. 



A Non-Volcanic Crater. 



TiiR crater of Coon Butte, .Arizona, is of a remarkable 

 nature, in that it contains no volcanic rock whatever. 

 This appears at first sight to be somewhat paradoxical, but 

 the theory is now generally accepted that the crater was 

 not formed by the extrusion of material from below, but 

 was the result of the impact of an enormous meteorite 

 falling with a tremendous velocity on to this portion of our 

 globe. This is in variation of the theory which was ad- 

 vanced in 1S96, by G. W. Ciilbert, that the crater, although 

 exhibiting no volcanic rock, is essentially volcanic, having 

 been produced by an explosion of steam generated by some 

 subterranean volcanic intrusion. This particular district in 

 .\rizona has long been remarkable for being the source of 

 many thousands of masses of meteoric iron, and whenever 

 meteors come to be spoken of, those of Arizona arc always 

 the first to be referred to. These masses weigh from a 

 thousand pounds down to a few ounces. A detailed ex- 

 amination has been taking place, and this has revealed 

 several thousand additional masses, adding about another 

 ton to the ten tons and upwards already found, ^^■e can 

 conceive of a gigantic meteorite weighing many scores of 

 tons, travelling for ages as a small planet, and finally dash- 

 ing earthwards. Then as it neared that part of the earth 

 where w'as the American Continent, it suddenly exploded, 

 sending fragments all around, and riddling the soil of the 

 Canyon Diablo with thousands of missies, whilst the main 

 mass struck the earth where now is found the Coon Butte. 

 Besides iron, the meteorites have been found to contain 

 large quantities of the magnetic oxide of iron, with nickel, 

 iridium, and platinum. The crater is now being explored, 

 and meteoric masses have been found therein at depths 

 varying from 300 to 500 feet, with a large amount of 

 minutely pulverised silica, and fragments of limestone, 

 whilst volcanic rocks arc conspicuous by their absence. 



Intrusive Craters in the Moon. 



The- formation of a cr.ilcr by intrusion instead of by 

 e.xlruiiun is a phenomenon of extraordinary interest, and 

 astronomers might well consider the possibility of the forma- 

 tion of some of the Moon's craters by a similar process. 

 It has always seemed to me that there is a remarkable 

 likeness in the form of lunar craters to the rising walls 

 around a point in a liquid where a body has fallen in from 

 without. The " splash of a drop " may, perhaps, give a 

 due to their formation, now that the theory of intrusion as 

 the cause of the crater of Coon Butte has come to be so 



stablished. 



Pacific Depths. 



In iSij9 the United States steamer Nero was engaged in 

 the survey of a route for the trans-Pacific cable. From a 

 report wliich has now been issued, we find that several 

 submarine mountain ranges were encountered, one, east 

 of Guam, having peaks rising to a maximum of 6Sg 

 fathoms below the sea-levels, whilst the valle\-s descended 

 to depths of more than 5,000 fathoms. Four soundings 

 below the 5,000-fathom line were made in the abyss now 

 known as the " Nero Deep." The deepest, 5,269 fathoms, 

 was about se\'entj'-five miles ea.st-south-east from the island 

 of Guam, and is the deepest sounding ever recorded, being 

 only sixty-six feet less than six statute miles. 



Upper Carboniferous Rocks of West 

 Devon. 



The winter meetings of the Geological Society of London 

 opened on November 7, with a paper by Mr. E. A. Newell- 

 .\rber, on " The Upper Carboniferous Rocks of West 

 Devon and North Cornwall." The author had been at 

 immense trouble to accurately survey the coast-sections 

 south-west of Bideford, and the result was seen in his 

 comprehensive paper. Special attention was given to two 

 lithological types — (i) the Carbonaceous Rocks, which con- 

 tain inconstant and impersistent beds of the impure, 

 smutty coal, known locally as "culm"; these beds have 

 yielded plant-remains ; and (2) Calcareous Rocks, partly of 

 marine and partly of freshwater origin, consisting of well- 

 marked, impersistent bands of impure limestone, and con- 

 glomeratic beds of calcareous nodules embedded in shales. 

 One of the limestone-bands, the Mouthmill Limestone, is 

 marine, and contains an abundant fauna ; w'hile in others 

 the only fossils are Calamifes sucknwi and Alethopteris 

 Innchilica. The calcareous nodules, which are not ferru- 

 ginous, occur in thin shale-beds, 2 to 3 feet thick ; they 

 commonly contain a marine fauna, with goniatites, lanielli- 

 branchs, and fish-remains. The conclusion was reached 

 that Ihe rocks belong to the Middle Coal-Measures, and 

 lliat there is no evidence of Upper Coal-Measures. 



Porphyritic Crystals in Granite. 



I note in the Quarry, some illustrations by J. T. Rodda, 

 of Eastbourne, of a cruciform twin-cryslal of felspar in 

 Cornish granite, a remarkably fine specimen, and of a 

 porphyritic crystal of felspar in similar granite, showing 

 /onal inclusions. It is remarked that there is a good deal 

 of this coarsely crystalline granite, with conspicuous felspar 

 crystals, in London buildings ; and when polished these 

 granites give an opportunity for very interesting mineralo- 

 gical studies, not only with regard to twinning, but also 

 with respect to the regular zonal inclusions of other 

 minerals, which have often been built in the felspars, mark- 

 ing successive stages in the growth of the crj'stal. 



ORNITHOLOGICAL. 



By W. P. PvcRAiT, A.L.S., F.Z.S., M.B.O.U., &c. 



The Black-Headed Gull. 



The Cimiberland County Council have requested Messrs. 

 Thorpe and Hope, of the Carlisle Museum, to prepare a 

 report on Ihe food of the black-headed gull {Larus 



