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THE AUSTRALIAN MUSEUM MAGAZINE. 



Greeks called them " Betyls," probably 

 from the Hebrew word Bethel, meaning 

 home of God. From about 300 B.C. 

 to 300 A.D. coins or medals were 

 struck by kings in honour of these 

 supposed divinities. 



A great number of theories have been 

 put forward to account for the origin 

 of meteorites, but as Professor Sir T. 

 H. Holland has said, "the number and 

 variety of theories concerning a sub- 

 ject often forms a coefficient of our 

 ignorance." All that can be said with 

 certainty is that they come from out- 

 side our atmosphere and perhaps from 

 outside the solar system. 



The size of meteorites varies very 

 considerably ; for example the " Ah- 

 nighito " meteorite found at Cape York, 

 Greenland, in 1818, weighed thirty-six 

 and a half tons, while another found 

 at Muhlau, near Innsbruck, Tyrol, in 

 1877, weighed only seventy-seven 

 grains. The largest meteorite yet 

 found in Australia, at Cranbourne 

 near Melbourne, Victoria, weighed three 

 and a half tons, and is now preserved 

 in the British Museum (Natural His- 

 tory), London. 



The external appearance of meteor- 

 ites also varies ; some are quite smooth, 

 while others have characteristic in- 

 dentations which have been called 

 "thumb-marks"; some are more or 

 less spherical or pear-shai>ed, others 

 are quite irregular. 



The analysis of various meteorites 

 has not led to the chscovery of any ele- 

 ment that is not found in the material 

 of the earth ; on the other hand only 

 about one -third of the elements found 

 in the earth have been found in meteor- 

 ites. However, certain chemical com- 

 pounds are found which do not exist, 

 or at least have not been found, as 

 terrestrial minerals, for example old- 

 hamite (monosulphide of calcium), 

 troihte (monosulphide of iron) and 

 schreiberite (phosphide of iron and 

 nickel). 



The chemical composition of meteor- 

 ites is by no means constant, and they 



The " Bugaldie * Meteorite (siderite) 

 found at Bugaldie, near Goonabara- 

 bran. New South Wales. Note the 

 comparatively smooth surface. 



[Photo.— G. C. Clutton. 



have been classified according to this 

 variation into four classes, the first of 

 which is represented by the metallic 

 meteorites or Siderites. These are 

 composed essentially of various alloys 

 of iron and nickel. They are magnetic 

 and look exactly like a mass of metalhc 

 iron ; in fact when the " Delegate" 

 meteorite was discovered near Delegate, 

 New South Wales, by Mr. Alex. Pauline 

 in 1913, one of the local explanations 

 of the meteorite was that it was either 

 a bag of bullock bells smelted together 

 by a bush fire or a small blacksmith's 

 anvil that had suffered the same fate. 

 However, the want of homogeneity in 

 composition is seen when a polished 

 siirface is treated with bromine or other 

 suitable etching agent. OAving to the 

 difference in solubility of the various 

 constituent alloys, a regular pattern 

 is etched on the surface and is known 

 as a Widmanstatten figure. 



