combustion are led outside through a flattened chimney, t, resting at o on the center of the reflector. The air enters through the cover of the lamp and reaches the interior through a series of apertures in the circumference of the cast-iron bell which supports the reflector. There is no communication whatever between the interior of the lamp and the interior of the car, and thus there is no danger of passengers being annoyed by the odor of gas. By means of a peculiar apparatus, f, the flame may be reduced to a minimum without being extinguished. This arrangement is at the disposition of the conductor or within reach of the passengers. For facilitating cleaning, the lamps are arranged so as to turn on a hinge-joint, m; so that, on removing the reflector, o, it is only necessary to raise the arm that carries the burner, r in order to clean the base, s, without any difficulty. On several railways both the palace and postals cars are also heated by compressed oil gas; and lately an application has been made of the gas for supplying the headlights of locomotives (see figure), and for the signals placed at the rear of trains. But one of the most interesting applications of oil is that of LIGHTING BUOYS, in which case it is compressed into large reservoirs placed on a boat. The buoys employed are generally of from 90 to 285 cubic feet capacity, affording a lighting for from 35 to 100 days. To the upper part of the buoy there is affixed a firmly supported tube carrying at its extremity the lantern, c. The gas compressed to 6 or 7 atmospheres in the body of the buoy passes, before reaching the burner, into a regulator analogous to the one installed on railway cars, but modified in such a way as to operate with regularity whatever be the inclination of the buoy. In the section showing the details of the lantern on a large scale the direction taken by the air is indicated by arrows, as is also the direction taken by the products of combustion. These latter escape at m, through apertures in the cap of the apparatus. [Illustration: COMPRESSED OIL GAS FOR LIGHTING CARS STEAMBOTS, AND BUOYS.] The regulator, B, in the interior of the lantern, brings to a uniform pressure the inclosed gas, whose pressure continues diminishing as a consequence of the consumption. The lantern is protected against wind and waves by very thick convex glasses set into metallic cross-bars, c. The flame is located in the focus of a Fresnel lens, b, consisting of superposed prismatic rings, and adjusted at its lower part with a circle, d, while a conical ring, e makes a joint at its other extremity. This ring is held by the top piece of the lantern through the intermedium of six spiral springs, c' c''. Under the focus of the flame there is placed a conical reflector of German silver, t.