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.

  • Uno von Troil
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.

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    may now and then be obtained with difficulty. This fame circumftance may be ob- ferved of the trapp. Its fpecific weight is about 3000, and that of the trapp about 2990. It becomes fine by cutting, and po- llfliing. The more fine kind of trapp the fame. It yields an afli-coloured powder. The trapp yields rather a powder of a more light colour. It foon melts to black glafly flags. The trapp likewife. The bafalt is attacked by fal fodse with an effervefcence that fbon ceafes, and though fome feparation enfues, the greater part however remains un- diffolved. Borax perfectly folves it without effervefcence, and gives a clear iron-coloured glafs. It is folved with great difficulty by fufi- ble urinous fait, and whilft: cool- ing becomes of a whitifli grey, and opake. The fame effects are produced by thefe acids upon the trapp. One
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