MINERALWATERS. 



Mineral acid, which was set free from the lime, by the ad- 

 Waters. Jjt i on of the oxalic acid : or the solution may be 

 ^""""Y""**' evaporated to dryness, and exposed to a red heat, for an 

 hour ; if it contain muriate of lime, and magnesia, in 

 union with nitric acid, the latter salt will be decompos- 

 ed. On exposing the residue to the air, the presence 

 of muriate of lime will be known by its attracting mois- 

 ture. 



76. Muriate of Magnesia. Separate the sulphuric 

 acid by baryta, filter, evaporate to dryness, and dis- 

 solve the residue in alcohol. Again, evaporate and dis- 

 solve in water. If muriate of magnesia be present, it 

 will be dissolved, and if carbonate of lime cause no pre- 

 cipitation, and if no precipitate be formed, by evapora- 

 tion and the addition of sulpuric acid and alcohol, then 

 the fluid contains only muriatic acid and magnesia, in 

 union with each other. But, along with these, there 

 may be nitric acid, and lime or alumina, or both. We 

 must therefore determine if, in this case, the muriatic 

 acid and magnesia be in combination with each other. 

 For this purpose, precipitate the lime by evaporation, 

 and by the addition of sulphuric acid and alcohol, and 

 drive off the acid with which it was in union, by boil- 

 ing ; then add oxalic acid, and the magnesia will be 

 thrown down in the course of 24 hours. Subject the 

 fluid to distillation, and ascertain if it contain muriatic 

 acid (43.); if it does, then the fluid contained muriate of 

 magnesia. 



77. Muriate of alumina. If any free alkali be pre- 

 sent, saturate it with nitric acid ; then separate the sul- 

 phuric acid by nitrate of baryta. If the fluid after this 

 give a precipitate with carbonate of lime, it contains 

 muriate of alumina, or muriate of iron. Whether it 

 be alumina or iron, or perhaps both, may be known 

 by dissolving the precipitate in muriatic acid, and ap- 

 plying the tests of these substances, ( 50, 53.) 



Of the Methods followed for ascertaining tfie quantities 

 of the different compounds cont. lined in Mineral Wa- 

 ters. 



In ascertaining the quantities of the different com- 

 pounds in mineral waters, the steps to be followed 

 must, of course, vary in every different case, according 

 to the substances contained in the water. A few ex- 

 amples will suffice to illustrate the methods employed. 



In fixing the quantities of the different compounds, 

 we may state them either in their crystallized condi- 

 tion, in which case they generally contain water ; but 

 it is better, if possible, to reduce them to dryness. This 

 is done by exposing them to a red heat for sometime, 

 by which the whole of the water is driven off. Some 

 of the salts which we procure undergo decomposition 

 when subjected to a strong heat ; such is the case with 

 the carbonates and some others. We cannot, therefore, 

 in this way, ascertain their quantity in the dry, or, as 

 it is called, real state. We may Jo this, however, by de- 

 composing them, ascertaining the quantity of the pro- 

 duct, and finding how much of the decomposed salts is 

 necessary to form these products. 



78. Nitrate of Potassa. To ascertain the quantity 

 of nitrate of potassa, suppose it exists in water, along 

 with sulphates, and muriates of the alkalies, decom- 

 pose these by the acetates of baryta and silver. Af- 

 ter filtration, evaporate to dryness, and digest the resi- 

 due in alcohol, which will dissolve the acetates formed, 

 and will leave the nitrate. 



79. Nitrate of Lime. Suppose this contained in the 

 water along with muriates of soda and lime, evaporate 



to dryness, and digest the residue in alcohol, which will 

 dissolve the earthy salts, and leave the muriate of soda. 

 Evaporate the alcoholic solution to dryness, and weigh 

 the residue, after being dried ; then dissolve it in water, 

 and ascertain the quantity of muriatic acid, by precipi- 

 tation with nitrate of silver (43.) ; this will give the 

 quantity of the muriate of lime, which, subtracted from 

 the weight of the residue, leaves that of the nitrate of 

 lime. 



80. Carbonates. By boiling the fluid after it has 

 been deprived of its sulphuretted hydrogen, (56.) the 

 carbonates are precipitated, probably mixed with sul- 

 phate of lime. The carbonates may be that of lime, 

 magnesia, alumina, or iron ; the precipitate must there- 

 fore be digested in diluted muriatic acid, which will dis- 

 solve them all except the alumina and the sulphate of 

 lime. If any thing be left undissolved, it must be ex- 

 posed to a red heat, and weighed ; it is then to be boil- 

 ed in the solution of sub-carbonate of soda, and mu- 

 riatic acid added, to saturate the alkali. By boiling 

 the fluid, carbonate of lime, and alumina, if present,, 

 will be precipitated. Digest the precipitate in acetic 

 acid, by which the alumina will be left ; this, after be- 

 ing dried, will give the weight of the earth, and its 

 weight, subtracted from that of the residue, the quan- 

 tity of the sulphate of lime. 



81. Carbonate of Iron. The muriatic solution may 

 contain lime, magnesia, and iron. By the addition of 

 ammonia, the iron and part of the magnesia will 

 be precipitated. By digesting the precipitate in ace- 

 tic acid, the magnesia will be dissolved, and the iron 

 will be left. It must be dissolved in muriatic acid, and 

 precipitated by the addition of sub-carbonate of soda. 

 The precipitate, after boiling the fluid, must be washed, 

 dried, and weighed, which gives the weight of the car- 

 bonate of iron. 



82. Carbonate of Lime. The acetic solution of the 

 magnesia must be mixed with the muriatic solution ; to 

 this, sulphuric acid must be added, and the fluid evapo- 

 rated, and the sulphate of lime will be deposited. After 

 being dried, it must be weighed, and its equivalent of 

 carbonate of lime ascertained. 



83. Carbonate of Magnesia. By the addition of sub- 

 carbonate of soda to the solution, the carbonate of mag- 

 nesia will be precipitated. It must be dried and weigh- 

 ed. The solution, however, still contains sulphate of 

 lime, and carbonate of magnesia. It must therefore be 

 evaporated to dryness, and the residue washed with wa- 

 ter, which will dissolve the sulphate, and leave the car- 

 bonate. The weight of the latter of these must be add- 

 ed to that of the carbonate formerly procured. The 

 solution of the sulphate must be evaporated to dryness, 

 and the residue ignited, and the equivalent of carbo- 

 nate of lime added to that already mentioned. 



84. Alkaline Sulphates. The quantity of the alkaline 

 sulphates may be ascertained, by freeing the water of 

 the other sulphates, (70,) and then adding the solution 

 of acetate of baryta. 100 grains of the precipitate 

 are equivalent to 74.8 of dry sulphate of potassa, and to 

 61.2 of dry sulphate of soda. 



85. Sulphate of Lime. Add nitric acid, to decom- 

 pose the carbonates, boil the fluid, and add weak alco- 

 hol, the sulphate of lime will be precipitated. It must 

 be then ignited and weighed. 



86. Sulphate of Magnesia. If this be the only sul- 

 phate present, its quantity may be known, by precipi- 

 tating the sulphuric acid, and ascertaining the weight 

 of the sulphate of baryta, 100 grains of which =51 of 

 the sulphate of magnesia. If sulphate of lime be like- 



Mineral 



Waters. 



