HOW ON BRINE SPRINGS OF NOVA SCOTIA. 75 



hollow drill that has been proposed for boring holes in rock through 

 which a current of water is forced to carry oft' the ground stone, 

 and still more, the production of pot holes on our coasts and in the 

 hard beds of many rivers, by the moving water turning a stone in 

 a hollow and so gradually deepening it, until through time a cylin- 

 drical and deep cavity is formed. A lake basin is an immense pot 

 hole, in which the mass of ice that filled it took the place of the 

 moving stone, its grinding power vastly increased, and in great part 

 due to the moving glacier above it. The eroding action would be 

 slow, but it would be continuous, and the only limit in depth to its 

 power would be when the hydrostatic pressure of the water equalled 

 the weight of the superincumbent ice, a limit far beyond anything 

 with which we have to deal. The rock basins of Nova Scotia are 

 much shallower than those of Italy and Switzerland, because in the 

 one case the rocks operated on have been hard metamorphosed 

 schists and quartzites, in the other soft molasse, easily eroded ; the 

 work done being proportional to the hardness of the material. 



Art. IX. On some Brine Springs of Nova Scotia. By 

 Henry How, D. C. L., Professor of Chemistry and Nat. 

 Hist., University of King's College, Windsor, N. S. 



[Read March 6, 1865.] 

 In a former communication to the Institute,* and in another 

 paper, t read before the Natural History Society of Montreal, I 

 have given the composition of some of the mineral waters of the 

 Province, known or reported to possess medicinal properties. 

 Nearly all those analysed had for their leading ingredient sulphate 

 of lime, or plaster, as it is called, the exceptions being a brine from 

 the neighborhood of the Renfrew gold diggings, and that interest- 

 ing water from Bras d'Or, of which the chief constituents were 

 common salt and nearly as much chloride of calcium. In the 

 discussion which followed the reading of my paper at the Institute, 

 several springs were mentioned as locally famous, viz., those of 

 Earltown, Shubenacadie, and a place a mile and a half east of 

 Shelburne; but I believe no facts bearing on the composition of 



♦Trans. N. S. Inst., Vol. 1. t Canadian Naturalist, Oct. 1863. 



