30 
C. G. THORP, M.B., C.M. : 
like the Eastern button, though they may have one resembling 
the conical that is so derived, as is well shown by comparing the 
picture of the Australite in Dr. Suess’ paper with the Australite 
I show you (Plate XVIII, Figs. 3 and 4), you will notice the 
different size of the fracture facets and the different shapes of 
the portions of the bodies representing the inside of the bubble. 
I am of opinion that the apex of the West Australian conical 
Australite represents the outside surface of its bubble, while in 
the sections of buttons shown by Mr. Dunn the opposite is ap- 
parently the case, with their conical cores, of which Suess’ il- 
lustration is one. In fact, on more mature consideration I am 
more and more convinced that the Eastern and Western Austral- 
ites are of two types, and almost certainly are derived from 
different sources. The button form is the Eastern type, and the 
lens the Western. Apparently the former is produced from a 
more fluid and less viscid glass than the latter. 
Professor Kerr Grant believes that we are driven, for the 
reasons he states, to fall back on an extra terrestrial source for 
the origin of these Australites, Billitonites, and Moldavites, and 
he explains their very local occurrence, as being due to a small 
meteorite shower or possibly a recurrence of the same shower. 
Against this is : — 
1st. The different compositon of Moldavites when compared 
with Australites and Billitonites. These could not, therefore, 
be from one shower nor a recurrence of the same. All Australites, 
moreover, as I think I have proved, are not contemporaneous. 
2nd. Their different shapes. Australites are never found 
in the least resembling the shapeless Moldavites, specimens of 
which I have received recently from the Prague Museum. I have 
them here for your inspection (Plate XXI, Figs. 5 and 6). Molda- 
vites do, however, sometimes take more definite forms when in 
shape they closely approach tabloid Australites (Plate XXI, 
Figs. 7 and 8). 
3rd. All Australites and probably, judging from their 
identity of composition and from a paper I have read about 
them, all Billitonites consist of a very dark ferruginous glass, 
showing a remarkable uniformity of colour and appearance, 
whereas you have only to look at the few specimens of Moldavites 
that I am able to show you to recognise the entirely different 
quality of the glass of which they are composed, and the remark- 
able variability of its colour. 
4th. Glass is very rare in meteorites, and there are no 
other known entirely glass ones to the best of my knowledge 
and belief. 
5th. The world, for all we think it so big and important, 
is in reality a very small speck in space, and it is almost inconceiv- 
able that so small a meteorite stream should be passed through 
