An account of the hot springs in Iceland : with an analysis of their waters / John Thomas Stanley.

  • Stanley, J. T. (John Thomas), 1766-1850.
Date:
[1791]
Catalogue details

Licence: Public Domain Mark

Credit: An account of the hot springs in Iceland : with an analysis of their waters / John Thomas Stanley. Source: Wellcome Collection.

    10/106 (page 6)
    from It; and at the foot of the hills which bounded the valley. Several fragments of rocks, which had fallen from thefe, lay fcattered round our dation. Thefe were entirely volcanic; fome of dark blue lava, not unlike bafalte • others of a yellow fubftance; and again others of a grey lava, mixed with a great quan¬ tity of white glafs: but the mod: curious confided of jin heterogeneous mixture of various fubdances, ce¬ mented indifcriminately together by fome operation, fubfequent to their original formation, and fo ftrongly, that the rock was broken with difficulty by our ham¬ mers. It condded of pieces of black glafs, (a lava in all probability much vitrified), and large pieces of a clofe, grey lava, the cavities and pores of which were filled with zeolites finely radiated. Some pieces of black lava, in parts compa<d, and in other parts fo porous as to approach nearly to a pumice done, were mixed with the red of the mafs. A mixture of thefe fame fubdances, (the lavas, the glafs, and the zeolites), pounded in fmall grains, filled the fpaces between the larger pieces, and connefted the whole into a folrcl rock. The heat (if heat it was) which had cemented thefe materials, had not been drong enough to reduce any one to a date of fudon; for the angles of the frag-