Letters on Iceland: containing observations on the natural history of the country, antiquities, manners and customs of the inhabitants, &c. &c. Made, during a voyage undertaken in the year 1772, by Sir Joseph Banks, P.R.S. assisted by Dr. Solander, F.R.S. Dr. J. Lind, F.R.S. and several other literary and ingenious gentlemen / written by Uno von Troil ; with notes and additions by the translator. The whole revised and corrected by E. Mendes da Costa.

  • Troil, Uno von, 1746-1803.
Date:
1783
Catalogue details

Licence: Public Domain Mark

Credit: Letters on Iceland: containing observations on the natural history of the country, antiquities, manners and customs of the inhabitants, &c. &c. Made, during a voyage undertaken in the year 1772, by Sir Joseph Banks, P.R.S. assisted by Dr. Solander, F.R.S. Dr. J. Lind, F.R.S. and several other literary and ingenious gentlemen / written by Uno von Troil ; with notes and additions by the translator. The whole revised and corrected by E. Mendes da Costa. Source: Wellcome Collection.

    429/438 (page 395)
    One hundred parts of bafalt very finely powdered, and feyeral times dlgefted with frefli aqua regia, and then well wafhed and dried, leave fixty-eight parts undifiblved. The remainder of this fliews a little effervefcence before it unites with the fal fodae, and difiblves very little. It is diflblved with eafe by borax, and with difficulty by fufible urinous fait. It feems therefore to be a mixture of filiceous and gemmeous earth. The folution gives by precipitation with lixivium fanguinis as much Pruf- fian blue as is equal to twenty-fix parts in loo of iron ; though-the bafalt, by being tried in the ufual manner in the crucible, does not yield above ten in loo. This proves that lixivium fanguinis affords the moft exact me- thod of affaying iron ore. When at lafl; the folution is preci- pitated with cauftic volatile alkali, af- ter the iron has been feparated by lixivium fanguinis, faturated with acid, pure argillaceous earth is ob- tained. Some-