make one remark. Christian men are proved by their writings to have their hour of weakness and of doubt, as well as their hours of strength and of conviction; and men like myself share, in their own way, these variations of mood and tense. Were the religious views of many of my assailants the only alternative ones, I do not know how strong the claims of the doctrine of 'material atheism' upon my allegiance might be. Probably they would be very strong. But, as it is, I have noticed, during years of self-observation, that it is not in hours of clearness and vigor that this doctrine commends itself to my mind; that in the presence of stronger and healthier thought it ever dissolves and disappears, as offering no solution of the mystery in which we dwell, and of which we form a part."
Geological Survey of Indiana. By E. T. Cox. Pp. 494.
Yellow Fever Epidemic of 1873. By Jerome Cochran, M. D. Montgomery, Ala. 1874. Pp. 115.
Bulletin of the Buffalo Society of Natural Sciences. Vol. II., No. 2. Pp. 40.
Transactions of the Wisconsin Academy of Sciences, Arts, and Letters. 1873-'74. Pp. 254.
Double Stars. By S. W. Burnham, Esq. Pp. 13.
Catalogue of Forty-seven New Double Stars (same author).
Molecular Change in Iron and Steel by Electric Currents. By John Trowbridge. Pp. 10.
Freeing a Magnetic Bar from Earth's Magnetism (same author). Pp. 8.
Increase of Magnetism in Soft Iron by Reversal of Magnetizing Current. By W. A. Burnham. Pp. 9.
Artificial Butter.—The American Chemist for April contains a very full account of the manufacture of artificial butter, of which the following is a synopsis: Some years ago M. Mege Mouriez was commissioned by the French Government to make some researches with a view to obtain a product suitable to take the place of ordinary butter, to be sold at a much lower price, and capable of being kept without becoming rancid. M. Mege Mouriez placed several milch-cows on a strict diet. The animals were quickly reduced in weight, and gave a proportionately less amount of milk; but this milk always contained butter. Where could it come from? M. Mege Mouriez believed it was produced from the fat of the animal, which, being carried into the circulation, was deprived of its stearine by respiratory combustion, and furnished its oleo-margarine to the udder, and there, under the influence of the mammary pepsin, it was changed into butyric oleo-margarine, or butter. Guided by this observation, M. Mege Mouriez was not long in obtaining, by an ingenious process, from beef-suet a fat fusible at nearly the same temperature as butter, and of agreeable taste. He then transformed this same fat into butter by a process similar to that of Nature. His process is as follows: The fat of newly-slaughtered beef, of the best quality, is ground up between two cylinders, and then falls into a deep vat heated by steam, and containing for every 1,000 kilogrammes of fat, 300 kilogrammes of water, and one kilogramme of potassic carbonate, besides two sheep's or pigs' stomachs in small pieces. The temperature is then raised to 45 Cent, and the mass carefully stirred. At the end of two hours the fat all rises to the surface. It is then let off into another vat, heated on a water-bath to 30 or 40 Cent., and two per cent, of sea-salt added, to facilitate the depuration. In the course of two hours it becomes clear, and presents a fine yellow color, and the odor of freshly-churned butter. Having been carefully cooled, it is cut into cakes, packed in linen, and placed under an hydraulic press, and is then separated into two nearly equal parts, viz., stearine and liquid oleo-margarine. The stearine is used for making candles. After cooling, the oleo-margarine is passed through cylinders under a shower of water to wash it and give it consistence: it constitutes an excellent cooking-grease.
It is with oleo-margarine that M. Mege Mouriez, by operating in the following man-
