M. J. CRÉPIN, of Paris, “an enthusiast concerning the goat,” as M. de Parville calls him in _La Nature_, has established a model goat dairy, and is endeavoring to diffuse a taste for goat’s milk and its products. As a means to this end, he has sought to procure an improved breed of goats, and has obtained a stock of very satisfactory quality by crossing the best native goats with the Nubian buck. The latter animal is rather awkward in form and movement, but M. Crépin hopes to breed that out. Otherwise the Nubian is well acclimated, vigorous, and indifferent to cold, hornless, and a most excellent milker. Goat’s milk generally is richer in caseine than cow’s milk, and owes some of its special qualities to this fact, and to the further circumstance that the flecks of goat-milk cheese are smaller, softer, and more easily broken up--consequently more digestible--than those of cow’s milk. Further, goat’s milk is more nearly than any other common milk like in composition to human mother’s milk; and it has the very great advantage that, the goat being less subject to attacks of tuberculosis and other dangerous disorders, it is comparatively free from the liability to convey infection. A single objection to the general use of goat’s milk is the odor which is supposed to be characteristic of it, but M. Crépin affirms that this is not apparent when the goats are properly bred and kept. M. Crépin is experimenting with butter from goat’s milk, and represents that he finds it very nice. * * * * * The fundamental principle involved in the new form of telemeter, or instrument for estimating the distance of visible objects without actual measurement, invented by Herr Zeiss, of Jena, is that of the stereoscopic effect which appears in natural vision, where the inclination of the eyes in concentrating on the object gives the sense of distance. The base line between the eyes is increased in the Zeiss instrument by means of a system of prisms so as to give a widened base of binocular vision, and of mirrors which give magnifying power. Double images are formed, the distance between which varies in proportion to the distance from the observer, and appliances are provided for measuring how far apart they are. The arrangement is fairly satisfactory for moderate distances--say of 3,000 metres, or about 10,000 feet. * * * * * M. Moissan believes that he has found a solution of the problem of the manufacture of ammonia from the atmosphere, and consequently of rendering atmospheric nitrogen available in agriculture, by the artificial production of calcium nitride. While calcium undergoes no change in contact with nitrogen at the ordinary temperature, it is affected by it under the operation of heat, and finally burns in it, absorbing it rapidly and giving rise to a bronze-colored nitride. Thrown into water, this substance decomposes with effervescence, producing ammonia and calcium hydrate.