subjected to a high temperature would be rendered easier by a determination of the electric conductivity of various specimens.

Art. LIV.—Analyses (Technical) of New Zealand Coals. By Dr. W. P. Evans. [Read before the Philosophical Institute of Canterbury, 2nd November 1898. Methods used in determining the Given Quantities. 1. Water.—Coal (3 gr. to 6 gr. in platinum boat) heated in toluol bath*Trans. N.Z. Inst., vol. xxx., p. 495. (107° C), in current of dry coal-gas, and water given off absorbed in weighed chloride of calcium tube. Time of heating, three hours. 2. Ash.—The dry coal, from water-determination, heated in platinum boat over flat Teclu burner till of constant weight. 3. Sulphur.—-Eschka method, spirit flame only being used; checked where result seemed abnormal by Carius method. 4. Coke.—Muck's normal test in closed platinum crucible over free Bunsen flame.† Muck, “Steinkohlenchemie,” p. 8. Heating continued for thirty seconds after disappearance of luminous flame. 5. Heating Effect.—The values given are calculated according to a formula suggested by the American Coal Analysis Committee in their preliminary report. ‡ Chem. News, 1898, p. 75. As the heating values 6f coals Nos. 1–10 had previously been directly determined by means of a Hempel calorimetric bomb, I was able to compare the values given by the formula with those obtained by absolute combustion. As these values, together with other details regarding coals Nos. 1–10, will shortly be published, I need here only remark that the American formula gives very good results for the hard coals (1-5), but that in the case of the brown coals (6–10) the values, though in the same relative order as those determined by actual combustion, are not so widely differentiated.