12 Annals of the South African Musemn. 



appeared in two different meteorites in one locality may be reasonably 

 regarded as additional support for the view that the two pieces had 

 a common origin. 



In attempting to reproduce the original shape of this hypothetical 

 meteorite, and to explain the mode of bursting, as far as can be 

 inferred from a model of the Vienna specimen and the three photo- 

 graphs of the Cape Town one which are in front of me, I may, for 

 comparison, make use of the Tucson Ainsa ring. 



From a consideration of the measurements alone, and for this 

 purpose I ignore the weights, the lower left quarter of the Tucson 



Fig. 2. The Tucson Ainsa Ring. (^-V Nat. Size.) 



Ainsa ring would give a piece like that in Vienna ; the portion to 

 the right — about three-eighths of the ring — would correspond to the 

 irregular block in Cape Town, while the remaining three-eighths 

 forming the thinnest part of the ring are wanting.* The hypothetical 

 ring thus completed would have a diameter of about 1 metre. 



The above hypothesis, based, as stated above, on the shape and 

 common locality of the two irons, is, however, contradicted by their 

 structure. Although both belong to the " Octahedral Irons with 

 lamellae of medium width," still the description of the appearances 

 presented by the etched surfaces will show that important differences 

 in structure exist, and I shall have, in conclusion, to return to the 

 above question. 



* It is unfortunate that nothing can be learned of the second of the two 

 smaller pieces mentioned by IMr, H. L. Rudlin, for it may be part of the missing 

 portion. 



