The following text may have been generated by Optical Character Recognition, with varying degrees of accuracy. Reader beware!

"TAE Marine Review Reinforced Concrete as a Building Material The utilization of reinforced concrete as a constructional material for various purposes for which masonry, wood, or ironwork has been previously employed, has undergone considerable development for Boats. (From the Scientific American.) as good condition as when first placed in the water. That salt water exercises no deleterious effect upon the cement sheathing is perfectly obvious; and al- though the boat has been in constant use A REINFORCED CONCRETE PONTOON FOR THE BRIDGE AT PAVIA. during the past few years. One of the most novel applications of the system, however, is that which has been evolved and perfected by a well-known Italian engineer, Signor Carlo Gabellini, oft Rome; namely, its adoption for the construction of boats and floating structures in gen- eral; such as. pontoons, floating bridges, and so forth. Signor. Gabellini first drew attention to the pos- sibility of extending such a system to maritime pur- poses, as far back. as the nineties; and in order to demonstrate the feasibility of the idea, built a small rowing boat capable of carrying some four or five people. The whole of thes." craft from keel to gunwale, including seats and rud- der, was carried in armored cement, and upon launching was kept in the water at Port d'Anjio for four years, to illustrate on a prac- tical scale that the immersed cement sur- face is not damaged by sea water and offers no suitable adherence surface to Seaweed and other marine growths. To- day the boat is. still in service, the hull never having once been cleaned, and is in for some eleven years, the surface is without the slightest pitting or traces of decomposition. During the whole of this period the hull has required no repairs whatever, which fact points to the dur- bank of the Tiber. Similarly, in this in- stance the whole of the building, includ- ing both the pontoons and the super- structure, was carried out in reinforced concrete. There are eight pontoons disposed in two outer rows extending to a_ total length of 67 feet by 21 feet beam. Each pontoon measures approximately 16 ft. in length by 9 ft. beam. They are of rectangular section, of the flat-bottom type, there being a slight batter of about 15 degrees from the bottom to water level, whence the sides rise vertically to the top of the structure. The shell is of the single-wall type, strengthened transversely by cross beams, also execu- ted in the same material. The iron skel- ton comprises iron rods of round section with iron network or expanded metal be- tween, around which the concrete is built. The pontoons after construction were towed to their destination and bolted firmly together in two rows, the inter- vening space of some 3 feet between each row being occupied by transverse rein- forced-concrete girder members extend- ing from the water level to the upper edges of the pontoons, placed at inter- vals so as to come in line with the trans- vening space of some 3 ft. between each giving continuous strength at those A FLOATING BRIDGE ON' THE PO SUPPORTED ON REINFORCED CONCRETE PONTOONS. ability and serviceability of reinforced concrete for such purposes. The signal success of this initial prac- tical experiment was followed in the same year by the construction of a float- ing chalet or boathouse for the Aniene rowing club, which is still moored to the points from side to side of the structure. The whole was bolted up to form a rigid homogeneous floating mass, the ends of the pontoons on the upstream face being wedged shaped to form cutwaters, the other extremities being left square in section. Upon this raft the boathouse