An analysis of the mineral water of Tunbridge Wells, with some account of its medicinal properties / by Charles Scudamore. To which are annexed some observations on the water with which Tunbridge Wells is chiefly supplied for domestic purposes. By Thomas Thomson.

  • Scudamore, Charles, 1779-1849.
Date:
1816
Catalogue details

Licence: Public Domain Mark

Credit: An analysis of the mineral water of Tunbridge Wells, with some account of its medicinal properties / by Charles Scudamore. To which are annexed some observations on the water with which Tunbridge Wells is chiefly supplied for domestic purposes. By Thomas Thomson. Source: Wellcome Collection.

    61/64 (page 55)
    \ brown colour is produced, more or less intense according to the quantity of lead present. I find that by means of this re-agent, a sensible discolouration is produced in distilled water, containing only one 200,000th part of its weight of oxide of lead in solution. But the use of this re-agent requires considerable precautions ; otherwise it acts only ambiguously, or may mis¬ lead altogether. Tin, silver, and various other metals, are thrown down dark-brown by this gas, as well as lead. When the water contains any iron, the discolouration by this gas is much greater than it ought to be, from the minute quantity of lead which it contains. This is the case in a very remarkable degree with the Tun¬ bridge Wells water. If the precipitate thrown down from this water by sulphuretted hydrogen gas, be dissolved in nitric acid, and the solution be evaporated to dryness, a yellowish white matter remains, which is insoluble in water, but dissolves in nitric acid with great facility. I conceive this effect to be owing to the presence of a little iron in the precipitate, which seems to act upon the nitrate of lead, when assisted by heat, and decompose a portion of the acid. At least I do not see how the insolubility can be explained in any other way. 2 —The alkaline sulphurets have been employ¬ ed as favourite tests for lead ; but when there is i