ADDRESS. 13 



In the Salt Range of mountains in Northern India saliferous strata 

 are referred with some doubt by Medlicott and Blanford to the Triassic 

 strata. 



In the Jurassic series (Lias and Oolites) salt and gypsum are not 

 uncommon. One well-known instance occurs at Berg in the valley of the 

 Rhone in Switzerland, where salt is derived from the Lias. Salt and 

 gypsum are also found in Jurassic rocks at Burgos in Spain. At Gap in 

 France there is gypsum, and salt is found in the Austrian Alps in Oolitic 

 limestone. 



In the Cretaceous rocks salt occurs, according to Lartet, at Jebel 

 Usdom by the Dead Sea, and other authorities state that it occurs in the 

 Pyrenees and at Biskra in Africa, where ' mountains of salt ' are mentioned 

 as of Cretaceous age. The two last-named localities are possibly uncertain : 

 but whether or not this is the case, it is not the less certain that salt has 

 been deposited in Cretaceous rocks, and, judging by analogy, pi'obably in 

 inland areas of that epoch. 



In the Eocene or Older Tertiary formations, rock-salt is found at 

 Cardona in Spain, and at Kohat in the Punjab it occurs at the base of 

 Nummulitic beds. It is also known at Mandi in India in strata supposed 

 to be of Nummulitic Eocene age. 



The record does not end hei'e, for a zone of rock- salt lies in Sicily at 

 the top of the Salina clays in Lower Miocene beds, and in Miocene 

 strata gypsum is found at several places in Spain, while salt also occurs 

 in beds that are doubtfully of Miocene age (but may be later) at Wie- 

 litzka in Poland, Kalusz in Galicia, Bukowina, and also in Transylvania. 



In Pliocene or Later Tertiary formations, thick beds of gypsum are 

 known in Zante, and strata of salt occur in Roumania and Galicia, whil© 

 in Pliocene rocks, according to Dana, or in Post-Tertiary beds, according 

 to others, a thick bed of pui'e salt was penetrated to a depth of 38 feet at 

 Petit Anse in Louisiana. This ends my list, though I have no doubt 

 that, by further research, many more localities might be given. Enough, 

 however, has been done to show that rock-salt (and other salts) are of 

 frequent recurrence throughout all geological time, and as in my opinion 

 it is impossible that common salt can be deposited in the open ocean, it 

 follows that this and other salts must have been precipitated from solu- 

 tions, which, by the effect of solar evaporation became at length super- 

 saturated, like those of the Dead Sea, the great salt lake of Utah, and in 

 other places which it is superfluous to name. 



Fresh-water. LaJces and Estuaries. 



I now come to the subject of recurrences of fresh-water conditions both 

 in lakes and estuaries. In the introduction to the ' Geology of India ' by 

 Messrs. Medlicott and Blanford, mention is made of the Blaini and Ki'ol 

 rocks as probably occupying ' hollows formed by denudation in the old 

 gneissic rocks,' and the inference is drawn that 'if this be a correct view, 



