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not yet deserved its name, so that many chemists, in- cluding some of the various State officials in America, fall back on the ultimate analysis to calculate the theoretical amounts of clay, spar, and quartz from the alkali, alumina, and silica found. But this is only begging the question of proximate analysis. It would be better to remedy the defects of, rather than to neglect, the rational method. That process is best carried out as follows : Two grammes of the dried clay are heated with 50c.c. sulphuric acid and lOOc.c. of water on a water-bath for four hours, and then allowed to stand over-night. The flask is then heated on a sandbath till the acid fumes strongly. After CERAMIC CHEMISTRY. 23 filtration the solution is analysed in the usual way, and the residue treated with 5 per cent, sodium carbonate solution to remove precipitated silica, and then treated as in ultimate analysis. Another method of proximate analysis is that of Lunge and Schochor, but it is devised chiefly for testing the cement value of marls. In principle it is similar to the Lawrence Smith method for determining alkalies. The clay is treated with lime, which most readily attacks the combined silica and the finely divided free silica. By sub- sequent treatment with hydrochloric acid, and the sodium carbonate, the unlocked bases and soluble silicates are removed, and the residue is simply that which was not decomposed by lime.