BY ROBERT L JACK, F.G.S., F-R.G.S. 63 



these conditions exist over a large portion of the western interior 

 of Queensland — that portion, in fact, where modern artesian 

 wells are now pouring out enormous volumes of water. I was 

 present at a meeting of the Geographical Society on 29tli May 

 last, when Mr. Thomson expressed the opinion that evaporation 

 (through internal and external heat) was sufficient to account for 

 the whole of the rainfall not carried off by drainage. It must, 

 indeed, if the same conditions of impermeable soil and excessive 

 solar heat observed in portions of the Western interior apply to 

 the outer edge of the artesian basin, where the water is 

 absorbed. But if these conditions apply, Mr. Thomson's 

 argument proves too much ; for it proves, to those who believe 

 that rainfall is the first cause of artesian water, that there is no 

 artesian water in the West. It is easier to imagine that the 

 conditions do not apply. 



At the January meeting Mr. Thomson gave "some remark- 

 able examples of the atmospheric condition of Central Australia," 

 in order to emphasize his remarks on the adequacy of evapora- 

 tion for disposing of that portion of the rainfall not carried 

 off by drainage. He is reported to have said : "In one of his 

 exploring expeditions my esteemed colleague and predecessor in 

 office, the Hon. A. C. Gregory, had several hard guttapercha 

 drinking mugs with him. They were left in camp one day on 

 top of the table. When the explorers returned in the evening 

 the mugs had disappeared, the only trace of them remaining 

 being a liquid glutinous substance on the spot where the mugs 

 had been left. On another occasion Mr. Gregory was camped 

 about a quarter of a mile from a creek, and it was necessary to 

 swim it. When returning to cainp Mr. Gregory wore a thick 

 pair of heavy moleskin trousers, and in swimming the creek 

 ■s\ith them on they were, of course, completely saturated ; but 

 after walking into camp the whole of the water absorbed had 

 evaporated absolutely, and the trousers were quite dry." The 

 heat on the date of the drinking-cup incident may have been 

 128deg., and as guttapercha will melt at 115 deg., I have no 

 doubt that Mr, Gregory contented himself afterwards with 

 pannikins of more difficult fusible material. As for the mole- 

 skins, they may have been thick and heavy when they left the 

 shop, but no one v/ho knows Mr. Gregory's active habits can 



