282 The connecting rods are steel ham- mered forgings. One end is forked to span the crosshead while the other end has a single locating face. The forgings as received have been roughed out all over. This is done at the plant where they are made in order 'that any imperfections that might exist may readily be discovered. The first finishing operation is to recenter the rod carefully and to fin- ish turn all the radial portions. This work is done in an engine lathe as shown in Fig. 5. The ends are next faced. It is essential that they be faced true for if they are tapered slightly a good bearing on the wrist and crank-pin boxes cannot be ob-_ tained. ' The next operation is to plane the flat surfaces at either end to make them conform to the wrist and crank- Many THE MARINE REVIEW pin boxes. This work is done on a drawcut shaper as shown in Fig. 4. This tool is also used in finishing the radial sweep of the forked end. In planing this section of the rod, the machinist feeds the tool down- ward as it traverses, thus cutting a radius. As his eye is the only judge of the depth of cut to take at each stroke, a high degree of skill is neces- sary to turn out a workmanlike job. After the planing operations are com- plete the rod is drilled and reamed to accommodate the bolts that fasten it to its boxes. This work is gen- erally done on a_ horizontal boring mill, the drills being guided by jigs. After drilling, the unit is carefully finished by polishing with abrasive cloth' and oil which removes all tool. . marks and imparts a good finish. (To be continued) Z ) Z Maryland' Shipyard Has Bight Sister Boats Near- ing Completion--One Has Made Its Trial Run ODAY, when the sentiment of the country #Teans' toward steel ship construction, it is interesting to find the wooden ¢ugboat holding its own. The -Bethlehen'*Steel Co., al- though one of the dargest steel man- ufacturers of the country, has learned that wooden tugs, in certain classes of service for which they are intended, have advantages over 'those made of steel, in addition to the lower first cost. The builders of small wooden boats, while not directly affected by the war needs, found a big increase in busi- ness due to the greater towage re- quirements of the steel companies and of the large -shipbuilding concerns. THE ARTISAN ON ITS TRIAL TRIP MADE OVER 12 KNOTS PER HOUR. TUGBOAT, 133 FEET LONG, EQUIPPED WITH TRIPLE EXPANSION, 1100-HORSEPOWER ENGINE One such builder, M. M. Davis & Son, Inc., New York, has had many orders for wooden tugs and now at 'its. Solomons Island, Md., plant, has , eight sister ships of that class nearing " completion. One of these, the Artisan, is shown 'in the accompanying illustration. She has.a length over all of 133 feet, with a 29-foot beam and a depth of 15 feet. In Mer recent trial trip, she made over 12*knots an hour. The keel and keelsons and _ the stem, frames and center keelson are all of oak construction. The sheath- ing is yellow pine. The main engine is a triple expansion unit built by the Bay State Iron Works, Erie, Pa. The SHE IS A MODERN June, 1919 New Boston Office N order to serve its rapidly growing interests im New Eng- land more adequately, The Pen. ton Publishing Co., publisher of Tue Marine Review, has estab- lished a new branch office in Bos- ton. This office is located at 426 Old South -building, 294 Washing- ton street. This expansion was found ad- visable in order that the unusually important maritime interests of the New England. coast could be more closely served. New England is a 'center for both wood and steel 'shipbuilding and the port of Bos- ton is one of the most important on the Atlantic seaboard. The New England office will be fully organized in both editorial and business departments. The ed- itorial work will be im charge of H. R. Simonds. During the war, Mr. Simonds was captain of Com- pany F, 317th Engineers, attached to the First Army corps, Amer- ican Expeditionary Force. He also brings to his work a broad engi- neering training. The business de- partment will continue. to be in charge of George D. Macdonald, who as heretofore will make his headquarters in New York. The Penton Publishing' Co.,, Cleveland, also publishes The Iron Trade Review, the Daily Iron Trade and Metal Market Re- port, The Foundry and Power Boating, and in addition to the new Boston office maintains branch offices in Chicago, Cincinnati, New York, Philadelphia, Pittsburgh, Washington, D. C., and Birming- ham, England. engine is rated at approximately 1100- horsepower with cylinders 18, 28 and 45 inches bore x 30-inch stroke. The condenser is built integral 'with the engine and has 1721 square feet of cooling surface. The two boilers are of the Scotch type, designed for a working pressure of 185 pounds per square inch and with a heating surface of 1500 square feet each. The shaft is 9% inches in diameter at the thrust and 10% inches in diameter in the tail shaft. The pro- peller is 11 feet 6 inches in diameter and is designed for about 100 revolu- tions per minute for a tug speed of 12 knots an hour. The tug is equipped with the usual accessories which include a circulating pump, a donkey pump, a feed and aif pump, feed water heater, wrecking pump and electrical generator. She also carries a wireless outfit.