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AURORA AUSTRALIS. Although in succeeding times, the highlands above were deeply buried under snow-fields, this deeply plateau locked basin could keep its ﬂoor for the most part unencumbered with water.

The atmospheric circulation, being distinct from that of the outer earth, presented special features. What was most to be remarked with respect to the atmosphere is that it contained a minimum of dust particles; so that, though the air was saturated with moisture, condensation seldom took place, except along he border lands, where fogs were very prevalent. The great rain storm, producing the ﬂood we experienced, was probably due to an unusual disturbance of anti-cyclonic nature, whereby dust-mote loaded air of the anti-trade belt above had descended, causing sudden condensation. The waters, continually draining into a central basin and there evaporating, led to the producion of a residual salt sea.

A knowledge of the strata underlying the basin would have been of the greatest value, but of course exposures were not available. However, a great accumulation of coal producing matter was presented in the jungle zone.

Extinct volcanic activity had been noted along the fault scarp, and specially interesting was the active