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raised, fresh water flowed down. The solvent power of the newly admitted water was of course greater than that of water partially saturated, and being also lighter it occupied the upper portion of the excavated space. The combined effect was to give the cavity the form of an inverted cone. The mode of extraction thus possessed the disadvantage of removing the greatest quantity of the mineral where it was most wanted for supporting the roof, and had given rise to occasional accidents to the pipes underground. These were referred to in detail, and the question was started as to possible legal complications arising hereafter from new bore holes put down in close proximity to the dividing line of different properties, the pumping of brine formed under the conditions described presenting an altogether different aspect from the pumping of water or natural brine. The second part of the paper referred to the uses to which the brine was applied, the chief one being the manufacture of common salt. For this purpose the brine, as delivered from the wells, was run into a large reservoir, where any earthy matter held in suspension was allowed to settle. The clear solution was then run into pans sixty feet long by twenty feet wide by two feet deep. Heat was applied at one end by the combustion of small coal, beyond which longitudinal walls, serving to support the pan and to distribute the heat, conducted the products of combustion to the further extremity, where they escaped into the chimney at a temperature of from 500 deg. to 700 deg. Fahr. On the surface of the heated brine, kept at 196 deg. Fahr., minute cubical crystals speedily formed. On the upper surface of these, other small cubes of salt arranged themselves in such a way that, in course of time, a hollow inverted pyramid of crystallized salt was formed. This ultimately sank to the bottom, where other small crystals united with it, so that the shape became frequently completely cubical. Every second day the salt was "fished" out and laid on drainers to permit the adhering brine to run back into the pans. For the production of table salt the boiling was carried on much more rapidly, and at a higher temperature than for salt intended for soda manufacture. The crystals were very minute, and adhered together by the solidification of the brine, effected by exposure on heated flues. For fishery purposes the crystals were preferred very coarse in size. These were obtained by evapo
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