of energy, and it is only the comparatively high cost of the fuel generally used in these—zin— which prevents them from being practically useful. A galvanic battery gives out very nearly the whole energy due to the chemical combinations which take place in it; so that it is hardly too much to say that, were a battery to be employed to drive an electro-motor, under suitable conditions, we could obtain at least sixty per cent, of the chemical energy, while the best-known steam-engine will only give about ten per cent, of the chemical energy of the coal and air consumed in its furnace. There is thus a large margin for the first cost of the substance to be consumed in the battery.—Saturday Review.
IT has been given to few scientific investigators to be more closely identified through their discoveries with the practical progress of the world, to see the fruits of their researches taken up and applied, made appreciable and beneficial in a greater diversity of lines, than to Robert Wilhlem Bunsen.
Professor Bunsen was born in Göttingen, March 31, 1811. His father was Professor of Theology, and of the Oriental Languages and Literature, in the University of Göttingen. Having passed through the course of the gymnasium, he entered the university, devoted himself to the study of chemistry and physics, and was graduated as a Doctor of Philosophy in 1830, publishing as his inaugural dissertation, "Enumeratio ac Descriptio Hygrometorum," or, "Enumeration and Description of Hygrometers." He afterward studied in London, Paris, and Vienna, and became, in 1833, tutor at the University of Göttingen; in 1836 he was appointed Professor of Chemistry at the Polytechnic school in Cassel; took the corresponding chair at the University of Marburg in 1838, and remained there thirteen years; then went, in 1851, to Breslau, where he planned a famous working laboratory; and in the next year went to Heidelberg, where he has for thirty years added to the fame of the great university.
His works in his chosen field have been numerous; their value, whether they are measured in relation to the advance of theoretical science, or as factors in the perfection of the operations of practical art, has been very great.
In 1834, in conjunction with Berthold, he published a research upon hydrated peroxide of iron as an antidote to arsenical poison, introducing a remedy which, having become universally known and universally accessible, may be regarded as a positive addition to the security of human life against a certain class of dangers.
He next, in 1835, described some singular compounds which the