IMMENSE SALT CONCRETIONS 187 



IMMENSE SALT CONCBETIONS 



By Professor G. D. HARRIS 



CORNELL UNIVERSITY 



Crystalline salt masses may be a mile in diameter! "Where are 

 they? How were they formed? Who said so? Interrogations like 

 these are sure to be forthcoming from layman, chemist and geologist 

 alike whenever such startling assertions are made. 



Salt is a common substance. Its occurrence in the waters of the 

 ocean, as well as those of land-locked, mouthless seas is a matter of 

 common knowledge. Interesting articles too, have been written re- 

 garding the immense layers of rock salt within the earth's crust. They 

 have told of the hundreds of years required in excavating the great 

 chambers and galleries in the Austro-Hungarian mines at Hallstadt, 

 Ischl and Weiliczka. Such mines have been the chose-a-voir for travel- 

 ers in this monarchy for the past two or three centuries. The Stass- 

 furt mines have become known throughout the world for the richness 

 of their potassium deposits. The Salt Mountain of Cordova, Spain, and 

 the Salt Cliff at Bahadur Khel, in the Trand Indus region of India, 

 are among the notable rock-salt occurrences. 



All these salt accumulations have been explained (and perhaps 

 properly) by supposing that they represent the residue of evaporated 

 saline waters, waters that occurred in cut-off bays or sounds, receiving 

 but occasionally supplies from the neighboring ocean, scarcely equaling 

 the vapors lost by evaporation. 



Of late an entirely new method of accumulation or growth of rock 

 salt masses has been discovered. Here the salt no longer occurs in thin 

 but wide-extended sheets, layers or strata, but in huge lumps, concre- 

 tions we may say, with vertical and horizontal diameters approximately 

 equal. These are the masses we wish here to bring to the attention of 

 the reader. We do not have to go to Spain or India to see these marvels. 

 They are, so to speak, right at home. They occur encysted in the sands 

 and clays of the later geological formations along our gulf coast, from 

 east Texas to south Alabama inclusive. Not all are immediately along 

 the gulf border, to be sure, but the majority are but a few score miles 

 from this line. All have doubtless a general conception of the low, 

 grassy marsh-lands of southern Louisiana with its intricate system of 

 tidal bayous beset here and there with dark green live oaks giving the 

 appearance of old-time great apple trees in a great meadow, when 

 viewed from a distant vantage ground. Doming up here and there in 



