American Journal of Science, March.—Some determinations of the energy of the light from incandescent lamps, by Ernest Merritt. Two series of experiments are described, which have been carried out for the purpose of determining what portion of the energy supplied to a lamp is given off as light, and what proportion is wasted practically as dark heat. In the first, based on Melloni's calorimetric method, the light is separated from the dark heat by passing the radiations to be measured through a thin layer of water, or, better still, through a solution of alum in water. The energy of the dark heat, which is almost entirely absorbed, is then measured by the rise in temperature of the water, and that of the light by a thermopile. In the second process the calorimeter was abandoned, and a cell, I decimetre thick, containing a strong solution of alum, was used for absorbing the dark heat. The light, after passing through this cell, was allowed to fall on a thermopile, and the deflection was observed. Then the alum cell was removed, and the deflection corresponding to total radiation was observed, the ratio of the two deflections giving the ratio of the light energy to the total energy. This being determined by electrical measurements, the energy of the light could be calculated.—On the ophiolite of Thurman, Warren County, New York, with remarks on the Eozoon canadense, by George P. Merrill. This ophiolite, a kind of verdantique marble, is found to be an alteration, or meta-somatic product after a mineral of the pyroxene group. Its constitution promises to throw some light on the Eozoon problem.—On the origin of the deep troughs of the oceanic depression; are any of volcanic origin?, by James D. Dana. A general survey of the oceanic regions leads to the inference that volcanic action can only have had a very subordinate part in determining the origin and position of the great marine depressions. Their source must be sought still less in superficial causes, such as erosion, but rather in the interior agencies of primordial development. The paper is accompanied by a bathymetric map of the Pacific and Atlantic, based on the recent charts of the British and United States Hydrographic Departments.—Description of a problematical organism from the Devonian, at the Falls of the Ohio, by F. H. Knowlton. These puzzling organisms, here provisionally named Calcisphæra lemoni, from the collector, have been submitted to various American and European palaeontologists, and the evidence both for and against the view that they are a fruit of Chara, is given in detail.—Papers are contributed by George H. Williams, on the geology of the Island of Fernando de Noronha (part 2, petrography); by S. L. Penfield, on some curiously developed pyrite crystals from French Creek, Delaware County, Pennsylvania, and on some crystallized bertrandites from Maine and Colorado; and by J. S. Diller and J. E. Whitfield, on dumortierite from New York and Arizona, peridotite from Kentucky, and gehlenite occurring in furnace slag in Pennsylvania.