THE FORMATION OF SALINE MINERAL WATERS. 831 



all the other groups which were deposited previously to it in the order 

 of evaporation. These consequences are constantly verified in the sa- 

 line beds which exist so numerously on the globe. Thus, to bring up 

 again the two most important salts, numerous beds of gypsum are 

 known, without rock-salt, or any of the other deposits, above them 

 which verifies our first conclusion ; but no bed of rock-salt is known 

 without gypsum which verifies the second conclusion. More than 

 this, a vast saline bed is now known which corresponds with the com- 

 plete period set forth in our list that is, with the complete period of 

 evaporation ; it is the formation at Stassfurt, Prussia, the disposition 

 of which corresponds exactly with that shown in the list. The study 

 of the Stassfurt bed further reveals an entirely new fact the pres- 

 ence, in a part quite above the mean of deliquescent salts, of an im- 

 portant deposit of boracic acid combined with magnesium. All the 

 geologists and engineers who have ever given their attention to the 

 Stassfurt deposit have been unanimous in calling for volcanic inter- 

 vention, and looking to the depths of the globe for the explanation of 

 the origin of the boracic acid, and the place it occupies in the upper 

 part of the bed ; and they have all also given a more or less prepon- 

 derant part to the play of volcanic agencies in the formation of the 

 whole. This conclusion was the more natural, because the ordinary 

 laws of chemistry seemed to oppose the probability of boracic acid, 

 even if it existed, being found in the last mother-waters. Borate of 

 magnesia is almost insoluble, and should have been among the first 

 and lowest of the substances deposited. Adhering to the principle 

 that there are no saline substances in the interior of the globe below 

 the sedimentary formations, I silenced my protestations as a chemist, 

 and applied myself to inquire if, contrary to all previsions, boracic 

 acid did not exist in the ultimate mother-waters of the salt-marshes 

 of the south of France. The result justified my geological induction 

 to a degree beyond all possible anticipation. Not only does boracic acid 

 exist in the ultimate mother-waters, but it exists there in a quantity 

 relatively so considerable that a single drop of the water is enough to 

 show it, either by the hydrogen method or by that of spectrum analy- 

 sis. Thus, the presence of this substance in the upper part of the 

 Stassfurt bed ceases to be an objection to the theory that the bed is 

 purely and simply the result of the evaporation of the ancient sea- 

 waters ; and its presence here furthermore gives a confirmation, as 

 striking as unforeseen, to that theory. 



My chemical and experimental studies are very far from constitut- 

 ing the only foundation for my theory of the sedimentary origin of 

 the saline formations of the globe. Existing nature offers us in abun- 

 dance, and on even a vaster scale than was shown in the ancient ages, 

 phenomena which it is sufficient to analyze to bring forth anew, even 

 to the slightest details, the manifestations which accompanied and de- 

 termined the precipitation of saline matters in the estuaries of the an- 



