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

ae: : THE Marine. REVIEW STEEL BARGES ON THE OHIO AND. MISSISSIPPI RIVERS.* "BY RICHARD J. DONOVAN. We may divide the business of river transportation into two general classes--first, that which pertains to bulk quantities, including such staple articles as coal, steel, grain, etc.; second, that which pertains to package quantities, in- cluding the general run of merchandise which may come in some form of package or in: quantities which will not war- rant special shipment. We find that in the case of the first class or bulk quantities the problem consists in 'simply loading the article considered in some type of carrier and delivering at some destined river port, without breaking or shifting individual cargoes. With the second class, package freight, there is more or less shifting or breaking cargo, with additions or subtractions at various points. Of course the handling of bulk quantities is by far the more interesting problem to the engineer, and it is here that the observer is astonished a the magnitude of such individual movements on our rivers. The total navigable mileage of the Ohio and all its tributaries is about 4,400 miles, the Ohio itself being about 1,000° miles 'from Pitts- burg to Cairo, where it empties into the Mississippi. The gross freight movement on this vast waterway system amounts to about 11,000,000 tons per year, the coal from-our Pittsburg district constituting about half of this tonnage. In handling this enormous business there are employed about 480 steamboats of all descriptions and some 6,000 or 7,000 barges. I might add that one company here in Pittsburg, the Monongahela River Consolidated Coal & Coke Co., owns upward of 100 tow boats of all descriptions, together with 3,000 barges, and ships annually about 4,000,000 tons of coal. may be divided into two classes--first, those provided with their own propelling machinery, such as the stern and side wheel steamboats; second, all carriers that have to be towed or moved by external means, such as the coal barge or decked merchandise barge. We would here note that a large number of craft are used in maintaining traffic, such as dredges, snag boats, derrick boats, repair and pump boats, | ew, the two general classes are the result of many years' experience and ,hard thought on the part of those engaged in the river business, and I may add that the types adopted are peculiarly fitted for the service. CONSTRUCTION OF RIVER CARRIERS. The final result in any design for a carrier on any 'water- way system is a compromise between adaptability for certain speed, draught of water available and carrying capacity re- quired, there being, of course, many other details peculiar to the service conditions. The requirements for a river steamboat, then, may be briefly stated to be (taking first the case of the packet steamer) such speed as has been found economical for the service engaged in, the least possible load draught, and such freight and passenger capacity as the usual run of business would warrant. In the case of the tow boat large reserve propelling power is an important item, and, due to the fact that coal barges leak more or less, there must be a large excess in boiler capacity for the purpose of operating the steam siphons which are used to keep the tow clear. The under water parts of the tow boat hull are as a rule not so fine as a packet boat--that is, they are not formed for such speed. They are not intended to carry cargo and the accommodations provided are generally but little in excess of those required by the crew. The boats are well supplied with all kinds of appliances and machinery for *From a paper read before the Engineers Society of Western Penney! vania, Pittsburg, Pa : ~The various types of carriers used on this great system - handling the tows and in the intricate and shallow channels are admirably suited for the purpose intended. In bulk transportation we have seen that coal is far in the lead as a staple product. The carriers used in this trade are divided by the river men into two classes, known respectively as the barge and the boat, both of which are rectangular in plan and resemble large open boxes. The ends of both are usually curved or raked from the bottom to the head blocks, as the ends which take the bumps and shocks are called. Bulkheads are fitted in some at each end, separating the rake end from the main cargo space. In passing TI would state that the barge is much used: in the Cincinnati and Louisville trade, while the boat is employed almost exclusively in the Mississippi river business. The barge is usually about 135 x 26 x 8 ft., and will carry between 15,000 and 16,000 bus. or nearly 600 tons on a draught of about 6 ft. 6 in. The boat is usually about 170 x 28 x 8 ft. 6 in. and will carry about 25,000 bus. or 950 tons. The barge is built in a very substantial manner and will last for some time, but the boat is merely thrown together and can stand but little hard usage. For some kinds of cargoes, such as sand and bulk merchandise, deck. barges are used. These are of various dimensions and built to stand the hardest usage. There is also a very important business on the Missis- sippi river in the transfer of railroad cars from side to side. These car ferries or transfer boats are generally of large dimensions and are supplied with their 'own power. There is also in use a number of transfer barges, built in the most substantial manner especially for this business. Up to the present time wood has held its own in river construction on account of its cheapness, for the wooden structure costs but one-half to one-third as much as the steel structure. However, suitable timber is becoming very costly on account of its scarcity, and the large operators are beginning to investigate the relative advantage of steel for their transport fleets. At present there are several examples in steel of the various types discussed operating on the Ohio river, and experience has shown that the steel hull is far superior to the wooden hull in cost of upkeep, while its life it double that of the wooden. THE TYPICAL STEEL: RIVER BOAT. We will now examine the construction of a typical steel river steamboat. The general principle involved in the construction of any. type of boat is usually embodied in arranging a longitudinal "backbone" consisting of longitud- inal bulkheads, keelsons and stringers. At right angles to the backbone is arranged a system of ribs or tranverse members, consisting of floors, side frames, deck beams and cross bulkheads. The shell or outside plating is then riveted to the skeleton frame. The bulkheads and_ shell plating are fitted. watertight, this being accomplished by proper spacing of rivets and judicious use of caulking tools. Some very interesting constrtiction is required to insure water tightness, but as a rule in shallow draught riv- er crafts the water pressure is so low that it is not. at all difficult to solve the problem. A complete or partial steel deck is usually provided and on this steel. foundation the wooden cabin and upper works are built. There is also usually provided a "hog chain system" to insure longitudinal strength. This is a truss arrangement. consisting of a square or round section rod carried over tube or timber bracing and leading from the bow of the boat to the stern. It usually projects above the cabins and is quite apparent. The aim is to make the structure as light as possible consistent with the required stiffness and strength for the service conditions. It is perfectly feasible to make an analytical study of the structure, of a boat, but in river work such an investiga- | | |