THE NARRABURRA METEORITE. 235 
External Structure._Mr. Russell mentions that the 
meteorite is much rusted, and is very irregular in outline, 
and contains large rounded holes. The usual coating of 
fused oxides is not present, it has probably been removed 
by long exposure of the meteorite to the weather, and its 
suriace is now merely rusty. He found its weight to be 
70 ids. 14 ozs., and its sp. gr. 7°57. The general appearance 
of the meteorite is shown by Plates 11 and 12, and the 
internal structure by Plates 13 to 22. 
The surface is deeply pitted, the largest of the pits are 
numbered and their principal dimensions given on the Plates 
11 and 12; from the depth and character of some of them 
they do not appear to have been formed by pieces splitting 
off, and it is probable that most of them have been formed 
by the melting of the fusible troilite and its fluxing action 
upon the adjacent metal; some may also have been in- 
creased by subsequent weathering. 
Sections.— On cutting the meteorite, with a power-driven 
hack saw, it was found to be very hard and especially in 
places near the troilite nodules and the dark bordered 
elongated crystals (see Plates 12 and 14). A record was 
kept of the loss in weight of the saws used, the weight of 
the sawdust produced was 1852°36 gms., and the loss in 
weight of the saws employed was 2°83 gms., so that the 
amount of steel from the saws, mixed with the meteorite 
sawdust was only about 0°15% In spite of the introduction 
of this steel, the sawdust obtained from a cut right through 
the body of the meteorite necessarily affords a better 
average sample for analysis than a portion cut off from one 
part of the meteorite. An allowance of course is easily 
made for the iron thus introduced. No oil or other lubricant 
was used in cutting and the saws were new and perfectly 
clean. 
