If, then, we may explain every thing by either theory, to which of the two shall we give the preference?
MRS. B.
It will, perhaps, be better to wait for more positive proofs, if such can be obtained, before we decide positively upon the subject. The new doctrine has certainly gained ground very rapidly, and may be considered as nearly established; but several competent judges still refuse their assent to it, and until that theory is very generally adopted, it may be as well for us still occasionally to use the language to which chemists have long been accustomed.—But let us proceed to the examination of salts formed by muriatic acid.
Among the compound salts formed by muriatic acid, the muriat of soda, or common salt, is the most interesting.[*] The uses and properties of this salt are too well known to require much comment. Besides the pleasant flavour it imparts to the food, it is very wholesome, when not used to excess, as it assists the process of digestion.
Sea-water is the great source from which muriat of soda is extracted by evaporation. But it is also found in large solid masses in the bowels of the earth, in England, and in many other parts of the world.
EMILY.
I thought that salts, when solid, were always in the state of crystals; but the common table-salt is in the form of a coarse white powder.
MRS. B.
Crystallisation depends, as you may recollect, on the slow and regular reunion of particles dissolved in a fluid; common sea-salt is only in a state of imperfect crystallisation, because the process by which it is prepared is not favourable to the formation of regular crystals. But if you dissolve it, and afterwards evaporate the water slowly, you will obtain a regular crystallisation.
Muriat of ammonia is another combination of this acid, which we have already mentioned as the principal source from which ammonia is derived.