Mr. A. P. Coleman, during some geological work last summer on the north shore of Lake Superior, about Heron Bay, discovered a new mineral, which he has named _Heronite_, and which he describes at length in the Journal of Geology for July-August. It is a dike rock, consisting essentially of analcite, orthoclase, plagioclase, and ægyrite, the analcite having the character of a base, in which the other minerals form radiating groups of crystals. The analcite clearly represents the magma left after the crystallization of the imbedded minerals, and it is evident that it can be formed only from a magma highly charged with water, and therefore under pressure. From the examination of a number of nearly pure hydrocarbons obtained from American petroleum by Young, it appears that the same classes of hydrocarbons, paraffins, polymethylene compounds of naphthenes and aromatic hydrocarbons are present in these and in Russian and Galician petroleums; but that Russian petroleum contains a relatively larger amount of naphthalenes and, in all probability, of aromatic hydrocarbons, than Galician, and Galician a larger amount of the same hydrocarbons than American petroleum. NOTES. An old contributor, Dr. A. F. A. King, of Washington, D. C., writes us calling attention to the interesting fact that we printed an article of his as far back as September, 1883, suggesting the mosquito theory of malaria, and giving a number of observations which seemed strongly to support this view. Experiments made by F. H. Hall and W. P. Wheeler, at the New York Agricultural Experiment Station, regarding the best food for "chicks, pullets, cockerels, and ducklings," seem to indicate conclusively that part of the protein must be drawn from animal sources if we are to get the best results. Rations in which from forty to fifty per cent of the protein was supplied by animal food produced more rapid growth and at less cost of production. Messrs. A. Stutzer and Hartlieb, of Breslau, have detected bacteria in Portland cements, which provoke the liberation of the nitrogen from nitrogenous compounds in water, and the formation of nitrous and nitric acids that act upon the lime in the cement and promote its disintegration. According to Industries and Iron, the tides are now utilized for generating power at Pont-l'Abbé, Finisterre, France, during fourteen hours per day. At flood tide the water flows through a canal two miles and a half inland into a pond in the rear of the power house, and returns to the sea at ebb tide. The total fall is seven feet and a half, and eighty-horse power is generated by means of turbines. Means have been considered for applying this method of generating power to various industries.