578 DR. URE ON THE MOIRA BRINE SPRING. 



of the opening. When a lump of coal is detached^ however, water soon afterwards 

 begins to exude in drops from the crevices of the seam. 



Immediately over the coal measures from which the saline water issues, there is a 

 stratum of remarkably fine fire-clay, a shale free from iron and lime, called by the 

 miners tow, about eighteen inches thick. This slate-clay is impermeable to water. 

 Immediately under the coal lies a stratum of soft clay eight inches thick, which rests 

 on a layer of compact slate-clay, several feet thick, also impermeable to water. 



The bed of coal, although it contain pin-cracks which seldom extend many inches, 

 has also the partings called slines, and those called cleavings in the direction of the 

 bed ; yet the coal is so little penetrable by water laterally, that it can confine by a 

 wall a few yards thick the water of old workings. 



When a fault has been perforated, water is seldom or never observed, so long as 

 the confusion of strata occasioned by the break continues to exist. But from the 

 parallel strata, the coal yields this saline water at almost every pore. The fault might 

 have been a rent of an immense depth, but the line of slip is filled up and glazed, so 

 to speak, by the incumbent pressure: hence in the greater number of instances 

 where salt water is formed and continues to flow, the source of this fluid cannot be 

 traced to the faults ; for although near some of these the water may be abundant, yet 

 generally the borders of the faults and the faults themselves are quite destitute of 

 water, acting as barriers to it in every direction. 



In consequence of the uniform distribution of saline matter through this coal, the 

 potters are unable to employ it in their kilns, for it gives their earthenware the well 

 known glaze due to the action of the vapour of chloride of sodium. 



Saline water is found in one or more of the sandy rocks of the strata above the 

 coal, but in very small quantity, and much less strongly impregnated than that which 

 issues from the coal. 



The brine-spring water is used for baths both at Moira and Ashby-de-la-Zouche as 

 a medicinal application. These are celebrated for their sanatory powers in rheumatic, 

 paralytic, and scorbutic diseases. Its internal administration, in small doses frequently 

 repeated, is said to accelerate the discussion of scrofulous swellings, and of broncho- 

 cele ; results which have been latterly ascribed to the combined agency of the bro- 

 mides of sodium and magnesium with chloride of calcium which are found in the 

 water. 



A considerable quantity of this water was sent to me for analysis in bottles well 

 corked and sealed*. Its taste is simply but strongly saline. It has no smell. It is 

 pellucid and colourless. Its specific gravity at 60° Fahr. is 1*04647. A glass balloon 

 being filled with it, the orifice was shut with a tight cork, from which a narrow bent 

 glass tube proceeded, so as to dip under the mercury of a pneumatic trough. The 

 balloon and tube were entirely filled with the water, to the exclusion of air. On the 

 application of heat, gradually increased till the water began to boil, the air contained 

 * By Edward Mammatt, Esq., superintendent of the mines and baths. 



