100 All Analysis of Sea-water; 



Of the different views which may be taken of the state of com 

 bination of the elements, I have already inferred, that the 



one 



which supposes the sulphuric acid to exist in the state of sulphate 

 of soda, is the most probable ; and as the mode of analysis by 

 reagents ie the most accurate, the last table may be cons'idered 

 as that which exhibits the nighest approximation to the real com- 

 position of sea-water, both with regard to its ingredients, and 

 their proportions, 



I had proposed to add a few observations on the analysis of 

 salt-brines ; but as they are merely applications of the principles 

 already illustrated, it is sufficient to stale them briefly, or to no- 

 tice those which present rather striking results. 



Klaproth has given a laborious investigation of the nature of 

 these brines ; in the greater number of them, he states as ingre- 

 dients, muriate of soda, muriate of magnesia, muriate of lime, 

 artd sulphate of lime. It is obvious that there are no just grounds 

 whence this composition can be inferred ; it is much more pro- 

 ■bable, that sulphate of soda is tlse ingredient, and that, acting 

 on a portion of the muriate of lime, it forms sulphate of lime. 



In other analyses, — in those, for example, of the salt-brines of 

 Lorraine, by Nicholas*, — muriate of soda, sulphate of soda, sul- 

 phate of lime, nmriate of magnesia, and muriate of lime, are 

 enumerated as ingredients. Here it is still more evident, that 

 there is no proof of the previous existence of sulphate of lime ; 

 on the contrary, as both muriate of liuie and sulphate of soda arc 

 present, they must, in the concentration of the liquor by evapo- 

 ration, form by their mutual action muriate of soda and sulphate 

 of lime ; and the quantity therefore of this sulphate which may 

 be obtained, must have this origin. 



t!ie water concentrated by cv?.poration, the c'tciir liquor, sf'erthf subsidence 

 of the precipitate being evaporated to dryness, the saline matter being ex- 

 posed to heat, to dissipate the m\niate of ammonia; being redisiiolved in 

 water the subcarbonate of ammonia again added, and this repeated for ;* 

 third, and even a fourtli time, the results gave the following proportions of 

 the elements : 



Lime, .... 2-9 grains. 



Magnesia, . . . lil- 



SSodu, .... D7''' 



Sulphuric acid, . \yf2 



Muriatic acid, . .''()-f# 



i;25-ti 



The principal difference here, is the proportion of magnesia being some- 

 what smaller, evidently owing to its precipitation by the carbonate of am- 

 monia, even with the aid of the methods employed to promote it, being im- 

 perfect. 



* Aim. de Chimie, t. xx. 



In 



