sons of the year. The existence of the lagoons, as sunken 

 aieas, is an advantage ,of the greatest practical importance 

 under present conditions ; indeed, nothing less than the salva- 

 tion of the country. By their existence the concentration 

 and localization of the saline substances become possible, and 

 by this means the higher lands are drained of their salt, and 

 rendered sweet. A flood in this country is an event greatly 

 to be dreaded. If the waters rise above their normal level 

 and empty themselves into the numerous cul de sacs which 

 tne configui'ation of the country supplies, the sweet herbage 

 is killed iip to the level of the storm waters, and a new flora, 

 of a salsolaceous type, takes its place. Several examples of 

 this deterioration of the soil, caused by a flood that occurred a 

 few years ago, were pointed out to me in my journey. Good 

 dark soil that had previously gi'own heavy crops was now 

 bare except for a few plants whose habits of growth fitted 

 them for a saline soil ; the white crystals of salt could be easily 

 recognised as glistening particles on the background of the 

 dark soil. In one situation affected in this way a farmer 

 showed me a well that was filled by the waters of the flood — 

 before the inundation the water was comparatively sweet, and 

 was used for farm purposes, but since the flood referred to 

 the water in the well is like brine, and quite useless. 



Fine examples of gypsum crystals can usually be obtained by 

 digging in the silt of the lagoons. The gypseous layer com- 

 mences about a foot from the surface of the lake deposit. 

 Some interesting examples, exhibiting complex twinning 

 are obtained in the Cape Spencer locality, but I had not 

 time to visit the spot. On the southern side of Lake Fowler 

 (the largest of the lagoons), a very remarkable deposit of 

 granular gypsum lines the shores of the lake in a range of 

 hills 80 feet high. The hills consist almost entirely of pure 

 gypsum in the form of small crystals the size of coarse sand. 

 In places the gypsum partakes of the character of a white 

 powder, resembling flour, and the deposit, as a whole, is so 

 pure that it is simply shovelled into sacks and carted away 

 to the mill for commercial purposes. How such a clean 

 deposit could have been formed, and in solid mass, so high 

 above the present level of the lake, are questions not easy to 

 answer. 



The association of gypsum and rock salt with dolomitic 

 limestones is so general an occurrence as to suggest com- 

 munity of origin. This subject has been dealt with very 

 fully by Dr. Sterry Hunt in his "Chemical and Geological 

 Essays/' and throws considerable light upon our present en- 

 quiries. In tile Murray districts and elsewhere in South 



