An investigation of the properties of the Thames water / by William Lambe.

  • William Lambe
Date:
1828
Catalogue details

Licence: Public Domain Mark

Credit: An investigation of the properties of the Thames water / by William Lambe. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    lime (though tlie taste did not correspond with it), finding sul- phuric acid to cause a small precipitate of sulphate of lime. 2. It is not easy to obtain this matter separated from common salt, with which it is combined. I first tried to procure it by digesting the soluble residuum in rectified spirit, but I obtained a mixture abounding in common salt, and the mass remaining was still deliquescent. 3. I next dissolved the soluble matter of tbe whole residuum of the water in a small quantity of water, and boiled and digested the insoluble residuum in a considerable quantity of water; which was filtered and evaporated to dryness. By this I separated the sulphate of lime, which was however of a yellow colour, and obviously united with deliquescent matter. The whole was now digested in rectified spirit, which extracted a small portion of the deliquescent substance, in a state as pure, I suppose, as it can be obtained in. 4. The solution in the rectified spirit is of a deep yellow colour, with which colour it tinges the saline matters united to it. The sulphate of lime was not deprived of this colour by the spirit. Evaporated it leaves a mass, partly yellow, partly white, on the glass, with the edges glossy and shining. It is highly deliquescent, and leaves when re-dissolved a yellow' stain on portions of the glass. Its taste, when concentrated, is sharp, but not acrid; diluted it is bitter with some degree of nau- seousness. 5. A very small portion of this matter was heated to redness at the bottom of a silver crucible. It seemed to be wholly de- composed by the heat. A little common salt and oxide of iron, with a trace of insoluble matter, was all that could be observed. I suspect that both of the former matters were accidental. 6. This matter has continued deliquescent, when exposed to the air, for many weeks. But in one example recently observed, and which was obtained as above described, it lost this property in a few days, as did the residuum of the water which had con- tained it. There must then be a variety in its composition. Nitrous Acid. 7. The small quantity, that I could procure by the treatment D