FLOATING WAREHOUSES. The danger that attends the storing of petroleum and other inflammable and explosive chemicals has led in France to the construction of warehouses, storehouses, or magazines that will float in a dock or basin, and can be moored at a distance from buildings on land. So far as concerns England, an act of parliament was passed in 1800, relating to time carriage and storing of dangerous sub stances; this law was amended and considerably extended by an act passed in 1875, applying to gunpowder and other cxploSive substances (inelnding nitro-glycerine, dynam ite, gun-cotton, blasting-powders, fulminate of mercury, fireworks, pereussion•eaps, etc.). This act requires such substances to be marked "gunpowder" or "explosive," and to be conveyed or stored with special precaution; it leaves much power to the sec retary of state to intervene in special cases and arrange the precise conditions. The storing of petroleum Is regulated by the act of 1871. In France, as we have said, F. W. have been constructed, two being finished in 1864, and others added in later years. The construction of the floating fabrics is remarkable. Each warehouse or magazine consists essentially of one hundred hollow iron cylinders, arranged in four rows of 25 each, firmly lashed or strapped together to form a kind of raft. Each cylin
der, 16 ft. long by 6 or 7 in diameter, has hemispherical ends, with a man-hole at one end. They are placed upright when in position, so as to be filled with petroleum, gly-• cerine, gunpowder, or any other substance, through the man-hold. AS they will hold 25 tons each, their united capacity is 2,500 tons. There is a wooden covering to the top of the collected mass of cylinders, and round the sides as far down as the line of flotation, to shield the iron from fluctuations of temperature. This covering is made of thick planking, fastened to the cylinders by angle-irons which have been riveted to the latter. At the head and stern are large hawser-holes, to admit hawsers for towing and mooring the floating fabric, bringing it into and taking it out of a basin or dock, and warping it to a quay or dock wall; or, when the vessel is moored in the middle of a basin, far away from buildings, a barge may deliver or receive the dangerous cargo, and thus the vessel be. kept altogether away from quays and wharfs.