Marine Salt.
"Water may contain marine salt, which may be ascertained by pouring into it some drops of a solution of silver; a white sediment will immediately be formed of the consistency of curdled milk, which will at last turn to a dark violet colour."
Fixed Alkali.
"Water may contain fixed alkali, which may be ascertained by pouring into it some drops of a solution of corrosive sublimate; when a reddish sediment will be formed."
Calcareous Earth.
"Water may contain calcareous earth and magnesia. Some drops of acid of sugar poured into the water, will precipitate the calcareous earth in whitish clouds, which will at length subside and afford a white sediment. A few drops of a solution of corrosive sublimate, will produce a reddish sediment, but very gradually, if the water contain magnesia.
"Note. To make these experiments with readiness and certainty, the water to be analysed should be reduced one half by boiling it, except in the case of the fixed air, which would evaporate in the boiling."
Having thoroughly studied the process, we began our experiments. The three first producing no effect, we concluded that the water contained neither fixed air, iron, nor copper; but upon the mixture of the nitrous acid, mentioned for the fourth experiment, we perceived a light substance settle upon the surface, of a whitish colour, and extending but a little way, which led us to believe that the quantity of sulphur, or of sulphurous vapours, must be infinitely small.
The fifth experiment proved that the water contained vitriolic salts, or at least vitriolic acid mixed with calcareous earth. We ascertained the existence of this acid, by pouring some drops of a solution of heavy earth into the water, which became white and nebulous, and the sediment that slowly settled at the bottom of the vessel appeared whitish and in very fine grains.