The CHAIRMAN. Admiral, taking the whole condition of the Navy, the battleships, cruisers, submarines, torpedoes, and personnel, in other words, the efficiency and preparedness of the Navy, what is the present state of efficiency of the American Navy?

Admiral STRAUSS. I think it highly efficient. I have just left the fleet, where I commanded a battleship, and I of course observed everything closely, and took part in the maneuvers and target practice. I am of the opinion that our fleet is very efficient. The CHAIRMAN. Admiral, we are obliged to you. Admiral STRAUSs. I thank you, Mr. Chairman.

(Thereupon, the committee adjourned to meet to-morrow, Tuesday, January 27, 1914, at 10.30 o'clock a. m.)

[No. 12.]

COMMITTEE ON NAVAL AFFAIRS,
Tuesday, January 27, 1914.

The committee this day met, Hon. Lemuel P. Padgett (chairman) presiding.

STATEMENT OF REAR ADMIRAL RICHARD MORGAN WATT, CHIEF BUREAU OF CONSTRUCTION AND REPAIR.

The CHAIRMAN. Gentlemen of the committee, we have with us this morning Admiral Watt, Chief of the Bureau of Construction and Repair.

The members of the committee will remember that when we were at Boston on the inspection tour last summer we were interested in the floating crane there, and some of the members of the committee expressed a desire that we should have some further information on the subject of cranes in general, the method of construction, use, etc. If you have any suggestions, Admiral, growing out of your general knowledge of cranes, and also of any hearings that have been had on the subject, the committee will be glad to hear you.

Admiral WATT. Mr. Chairman, I have prepared a statement in the line of argument which leads up to the floating crane, and have distributed sketches to which I shall refer.

The CHAIRMAN. Just pursue your own way.

Admiral WATT. And if I get into too much detail, if you will just indicate it

The CHAIRMAN (interposing). Just go ahead and give us such information as you desire.

Admiral WATT. I consider that the best appliance for handling heavy weights is an absolute necessity at every first-class navy yard. Every such navy yard may be called upon to do all the work of a shipyard producing and repairing the largest of vessels; that is, handling boilers, reciprocating-engine parts, and even complete turbines, but will also be called upon to handle turrets and heavy guns with great dispatch. It is possible that the success of a naval campaign may be dependent upon the rapidity with which battleships may visit navy yards and have their eroded, and therefore inaccurate, turret guns removed and replaced by new or relined, and therefore accurate, guns.

Admiral Strauss has been talking to you about that-
The CHAIRMAN. Yes, sir.

Admiral WATT. This becomes, therefore, a matter of the gravest importance and one well deserving serious study to insure its proper solution. As naval constructors are the users of the weight-handling devices when provided by the Bureau of Yards and Docks, we have

given this matter exhaustive study. At the request of the chairman of your committee, I am prepared to review hastily our study of crane development.

One hundred years ago, when vessels were of wood and no propelling machinery was fitted, the most difficult weights to handle were the ships' masts. The masts were built on shore, rolled down to the water's edge, floated off to the ship, got on end, and stepped by sheer hulks a set of sheer legs stepped or mounted on a float or hulk.

With the introduction of machinery, floating off to the ship of crank shafts, or boilers, or engine standards was impossible, and the next step in development was the fitting-out dock and sheer legs thereon. Sheer legs are indicated by figure 1, and, as shown by the diagram, figure 10, a weight suspended from sheer legs is capable of motion in a plane only, about like that [indicating].

Mr. BRITTEN. What sort of a device have you here [indicating], a groove?

Admiral WATT. A screw contained in a groove. Arrangements for rigging in and out assume various forms, but the form here indicated is a horizontal screw on which is a nut which traverses the heel of the inner leg in and out, and rigging in brings the sheer leg back to the dotted position.

Mr. BRITTEN. The principle is the ordinary stiff-leg derrick?

Admiral WATT. Yes, sir. If you will turn to the figure in the lower left-hand corner, figure 10, you will find the sheer legs pictured. Now, those sheer legs handled weights in vertical plane only. I have crossed a line in that sketch. Whenever you wanted to handle a weight it was necessary to shift the ship fore and aft along the sea wall so that the spot on which the weight was to be landed came vertically under the head of the sheer legs.

Mr. BRITTEN. You can lift straight up and down, but no other way? Admiral WATT. You can lift straight up and down and rig in and out over the cross line shown by figure 10.

Mr. BRITTEN. It would have to be on a straight line?

Admiral WATT. It would have to be on a straight line normal to the sea wall.

Notwithstanding the disadvantages, the sheer legs continued to be for many years the main weight-handling appliance of ship and navy yards. It reached its highest development in the 180-ton sheer legs of Chatham Dockyard in England and the 180-ton sheer legs of John Brown Co., of Clydebank, Scotland.

The Chatham sheer legs are illustrated and popularly described in London Engineering of July 21, 1905, pages 81-84, volume 80.

With the increase in size of ships and the importance of lessening the period during which the capital invested in ships was unproductive, more rapid appliances for handling weights became necessary for shipyard equipment, and there were developed stationary cranes of revolving type, floating cranes, and traveling gantry cranes. The stationary crane of revolving type possessed advantages over the sheer legs in that it could handle weights over the area of a circle instead of on a straight line only. It was not necessary to move the ship so frequently; further, revolution of the crane was much more rapid than rigging the sheer legs in and out.

Again referring to figure 10, the second picture on the lower line shows the larger range of the stationary revolving crane; in that weights

are handled over the area of a circle instead of on a straight line only. Consequently this crane could pick up weights anywhere within this circle [indicating], and land them, of course, anywhere within the circle, making it a much more useful tool. It, however, still necessitated moving the ship along the sea wall. It was much more rapid, because revolving the crane could be done much more quickly than rigging the sheer legs in and out.

The stationary crane took various forms, the ordinary double-cantilever type, the hammerhead or inverted double-cantilever type, the elevating-jib type, and so forth. A hammerhead crane is shown on sketch No. 3.

Mr. BRITTEN. What is this built up of [indicating the cantilever]? Admiral WATT. Steel.

The stationary revolving crane has reached its maximum development to date in the 250-ton crane at the shipyard of Blohm & Voss, Hamburg, Germany, where 250 tons can be lifted at an outreach of 83 feet beyond the edge of the sea wall.

The Japanese navy possesses a hammerhead or inverted doublecantilever type of crane at the Kure dockyard, which has 200 tons capacity at 105-feet radius, with 70 feet outreach beyond the sea wall, and, further, will hoist from 50 feet below the sea wall to 120 feet above the sea wall. It possesses also an auxiliary hoist of 30 tons at 160 feet radius. This crane is illustrated and described in London Engineering of March 15, 1912, page 350, volume 93.

Mr. BUCHANAN. Is that a revolving crane?

Admiral WATT. That is a revolving crane.

A second 200-ton crane of this type is found at the Fairfield Works, Govan, Glasgow, described in London Engineering of June 30, 1911, pages 842-843. Briefly, of capacity of 200 tons at 75 feet radius and 80 tons at 156 feet radius, and of hoist 145 feet above quay level to 45 feet below quay level.

The largest crane of stationary type in American shipyards is the 150-ton revolving derrick jib, electrically operated, found in the plant of the Newport News Shipbuilding & Dry Dock Co., illustrated by sketch No. 2 herewith, and described in detail in the Transactions of the Society of Naval Architects and Marine Engineers, 1898, page 195, volume 6. This crane will handle its maximum load of 150 tons within a ring of maximum and minimum diameters of 147 feet and 88 feet, respectively.

Probably many of you have seen that crane in operation.

To obviate the expense and risk attendant upon moving the ship, the traveling jib gantry crane was developed. It is illustrated by sketch, figure 4, and by the picture on page 11 of illustrations. This crane, of great capacity, travels upon tracks on the wharf or dock edge and of course serves a rectangular area limited only by the overhang of the crane and the extent of track. That is shown by the sketch in the lower right-hand corner of figure 10. The shaded section shows what area the traveling gantry at Fore River will cover. Because of the enormous weight upon the rails and the necessary placing of the outer rail close to the edge of the sea wall, as you will see on picture 11, the support or foundation for this outer rail is a very difficult engineering problem and a very expensive one to maintain. The folding jib gantry crane found its highest development

in this country in the crane possessed by the Fore River Ship Building Co. at Quincy, Mass.

Mr. BRITTEN. How is that crane operated? Is the inside of the structure anchored in any way?

Admiral WATT. Crdinarily the crane travels back and forth on cails, but when handling the extreme weight at the extreme overhang the crane is clamped to the inner rail. That is only for the extreme weight at extreme overhang. As shown in the picture on figure 11, this arm rigs up so that in moving along the track it can clear smokestacks or the masts of a ship.

Concurrently with the development of the stationary crane the floating cranes came into existence. The first floating crane of which I have been able to obtain any record was built in 1856 at the Delamater Iron Works from the designs of W. J. Bishop. This crane, rated of 60 tons capacity, is still in service at the yard of W. & A. Fletcher Co., of Hoboken, N. J.

London Engineering of May 30, 1873, page 73, volume 15, describes a 100-ton floating derrick, 71 by 66 by 13 feet, built to transport 100-ton blocks for a sea wall in lower New York, from the place where made to the place where laid. The description reads of "type of derrick projected by Bishop many years ago. This crane is still in use, and handled the turrets of the U. S. S. Florida as recently as 1910-11, when the yard crane Hercules was under repair.

In 1886 a floating crane was built for Tilbury Docks. London Engineering of July 30, 1886, page 119, volume 42, contains the following statement with reference to this crane:

CRANE FOR TILBURY DOCKS.

It will be remembered that on March 8 we reported the launch from the yard of Messrs. Sanuda Bros., Poplar, of a self-propelled floating crane designed and constructed by Messrs. Hunter & English, engineers, of Bow, London, E., under the patent of Mr. Walter Hunter, for the Tilbury Docks extention of the East & West India Dock Co.

This crane was successfully tried on Saturday, the 24th instant, in the Tilbury Docks. The hull is 110 feet long by 44 feet beam, with a depth of 9 feet. The crane is capable of lifting and swinging at a radius of 50 feet weights up to 50 tons, and of transporting them to any part of the docks or river, and of masting the largest ships in the port of London.

On the occasion of the trial the crane steamed down the dock with a load of between 50 and 60 tons which had already, for the purpose of saving time, been suspended from the jib or sheer legs. The vessel proved to be perfectly under the control of the twin-screw compound surface-condensing propelling engines which brought it with the greatest ease alongside the quay in the main dock where the load was to be landed. The load was then lifted and swung, and afterwards deposited upon the quay, the whole of the operations of lifting and slewing and regulating the balance-weight being under the absolute control of one man. The whole of the engines and machinery worked in the most perfect manner and gave great satisfaction to the assembled party. The great saving of time and expense which a crane of this type effects in the working of docks and harbors may briefly be summed up as follows:

1. It obviates the necessity of taking a ship from its berth to the sheer legs when heavy weights required to be taken from it or put on board, an operation which is always attended with some risk and considerable expense, entailing, moreover, the stoppage of all loading and unloading cargo while the ship is away.

2. The crane can steam alongside a vessel, take out or put in a crankshaft, boiler, heavy gun, or armor plate, and remove other heavy weights while the ordinary operation of loading and unloading are being carried out from the quay, or without shifting the ship, whether ironclad or trading vessel from its mooring.

3. The crane hull is constructed so that the guns, boilers, etc., may be placed upon its deck and steamed to or from any ship or any part of the dock or river where the