Mineral springs, dependent for their characteristic properties on carbonate of soda, appear to have been little noticed by chemists, and to have been still less attended to as curative means; at least in proportion to the multitude of cases in which that substance is administered in various other forms. Indeed the inference to be drawn from the silence respecting the modes of analysis adapted to such waters in our best elementary treatises, is that they have hitherto been very seldom met with. In one district, however, of Yorkshire, carbonate of soda is of frequent occurrence; it is found in the ordinary springs; often, at the same time with substances with which, in artificial solutions, or when concentrated, it, would be considered wholly incompatible; while at other times it is the predominant, or the only remarkable saline constituent. An analysis of a water of this kind, known by the name of the Holbeck Spa, has lately been published in the Annals of Philosophy, by my friend E. S. George; similar springs are found, I understand, as far [p022] westward as Bradford; they are numerous from the borings in and near Holbeck; while eight miles south, a water similar in its character, but differing in containing about twice as much alkali in the same measure, has been discovered at Stanley. About two miles from Wakefield, near the Aberford or York road, is an ancient mansion called Hatfield Hall; near the park or inclosure of which, in boring for coal, the spring in question suddenly gushed up, when the workmen had got to the depth of eighty yards, and has continued to run spontaneously, in all seasons, at the rate of six gallons per minute. The water at the spring is limpid and very sparkling; the portion which is allowed to escape, deposits upon the trough and in the channel through which it runs a quantity of sulphur; the smell is that of sulphuretted hydrogen; the taste, from the stimulus of the bubbles of gas modifying the softness of the alkali, rather pleasant than otherwise. The appearances presented by re-agents are,— With tincture of soap, a slight opalescence. Nitrate of silver, an abundant precipitate, partially re-dissolved by pure nitric acid. Sulphate of silver, a precipitate only partially soluble in nitric or acetic acid. Muriate of barytes, a slight precipitate. Lime-water, a precipitate soluble with effervescence in acetic acid. Oxalate of ammonia, no precipitate. On boiling, a slight pellicle appeared, soluble in nitric acid. Carbonate of ammonia, no precipitate, nor any on the subsequent addition of phosphate of soda. The water restored the colour of litmus paper slightly reddened. With tincture of galls and ferrocyanate of potash, no change. With muriate of lime, the water remained unchanged until heated; but when boiled, a copious precipitate took place. When concentrated by boiling, the water reddened turmeric paper, and effervesced strongly on the addition of an acid.