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14 MARINE REV LEW: : Disadvantages of Draw Bridges. _ Recent examples of drawbridge construction in the United States show that the disadvantages of this method of crossing navigable streams or inlets are at present being realized to their fullest extent. It is now a good many years since the competition between the great railway com- panies of Great Britain had the effect, first, of abolishing ferry links in the chain of transportation, and, second, of sending drawbridges of all kinds to join the defunct ferries. The rule for the English railway com- panies then became either high-level bridge or tunnel. High-level bridges were thrown across the Menai straits, the Frith of Tay, the Frith of Forth, the Tyne, and other navigable waters; while the Thames, the Mersey and the Severn were pierced by tunnels. These vast, and in most cases apparently unremunerative, engineering works were brought about to gain a saving in minutes, coupled with a thorough carriage between great cities. Fifteen minutes gain or loss in the five-hour run from Liver- pool to London seems a small matter, but when a ferry trip across the Mersey to Birkenhead was added to the few minutes' delay in reaching London, the sensitive through-passenger traffic practically deserted one great railway system and gave its patronage to another. It must be remembered, in this connection, that English railways always agree to charge the same rates between competing passenger points, 'so that the railway which labors under any natural disadvantage has to make up. for it, not by cheaper fares, but by increasing the frequency of its trains and generally improving its service. The tunnelling of the Mersey or the bridging of the Forth, therefore, instead of being a question of a few passen- ger fares more or less, becomes a policy upon: which the future prosperity of the investing railway may depend. But, ferries being inadmissible for the reasons already indicated, it may be asked why the English railway companies have shown such an antipathy to drawbridges. The answer to this is that all trains must slow down approaching a drawbridge, that the most important express trains are as likely to be delayed by its opening 'as the slowest freight*trains, and--a matter which English railway com- panies always carefully consider--every drawbridge has in it the possi- bilities of an accident, the damages of which would pay the additional cost of a perfectly safe high-level bridge or tunnel. Applying these remarks to the recent construction and equipment of drawbridges in the United States, we find that all the English objections to their use exist with even more force. Direct railway communi- cation between the largest cities in the country--New York and Chicago-- and their respective contiguous territory is dependent upon drawbridges. During the heavy morning or evening suburban traffic in these cities, the opening and closing of a drawbridge, no matter how quickly ac- complished,*means the stalling of half-a-dozen trains. The elaborate derailment plans, with special signals and signal towers, attached to all the railway drawbridges in the United States, bear eloquent testimony to the well-grounded fear that the best human agency must sometimes fail in keeping the moving train out of the open draw. Moreover, as all navigable waters in the United States are under federal jurisdiction, while 'the land on either side is under the control of the respective states, the natural conflict of interests thus engendered has resulted in making the federal authorities keep open to navigation every third-rate ditch which has uninterrupted communication with some main system of waterways, especially if it be in the neighborhood of a large city. Thus the railways, not having yet, except in a very few instances, decided that they must 'either tunnel or make high-level bridges near large cities, if they would 'give fast and uninterrupted passenger service, are compelled to rely on drawbridges. The type. of drawbridge most commonly used is the deep steel lattice girder, balanced on a central pier, which is surmounted by a turn- table drum. The width of clear channel which one of these drawbridges must expose when open varies from 50 to 200 feet. Probably the largest bridge of this kind was, until recently, the four-track structure belonging to the New York Central Railway crossing the Harlem river in New York city. The draw span is 400 feet long and 61 feet wide; when open, it gives two equal-sized channels of 165 feet each. In order that it may be opened and closed as quickly as possible, two fifty horse power steam engines with oscillating cyclinders are provided, and these are able to Open or close it in two minutes. A much longer bridge of the same general type was opened a short time ago between Duluth and Superior. This bridge, or rather its swing span, is 493 feet long and 59 feet wide, providing double railroad tracks, double trolley tracks, ordinary roadways and footpaths. When this bridge is opened, it gives two clear channels of 200 feet each. Curiously enough, with the same horse power as that of the great New York Central bridge, its span can be thrown open in considerably less time. The Duluth bridge, however, is worked by two fiity horse power trolley street car motors, fed by an electric current brought from an adjoining power house by submarine cable through the middle of the revolving drum, and they regularly open or close the swing span in 14% minutes. In Chicago, where the river is comparatively nar- row, a new form of drawbridge is rapidly coming into use. This is known as the Scherzer rolling lift bridge. It is of the bascule type, the leaves meeting in the center when the bridge is closed and rising wulpright on opposite sides of the river when the draw is open. As these bascule bridges, while obviously unsuited for very long spans, require no pier in the middle of the river, they are a distinct gain to navigation wherever they can be tised. Such bridges have two advantages, either for railroad or general use. One of these is that each leaf can be raised or lowered independently ot the other so that time may often be saved in this manner. The other ad- vantage is that when a leaf is up, it presents an unpassable barrier to ap- proaching trains or wagons. On this account it is well suited for elevated railways where trains run on very short headway and the possibilities of forgetfulness on the part of the engineer in regard to an ordinary swing span are very great. It is noted that the Eads bridge over the Mississippi was built without any draw span, and that the cantilever bridge over the Hudson at Poughkeepsie--the only one below Albany--has no draw span, and as time goes on there is little doubt that the railway companies, acting in the public interest, will find means to have many of the so-called navi-~ gable inlets and rivers of today crossed with fixed bridges of moderate elevation, instead of cumbersome time-absorbing draw-spans with which they are now equipped. There is something almost grotesque in the fact that the skipper of a fifth*rate tug boat has power at his pleasure to delay for ten minutes the entire through railway traffic of New York city, and a very large proportion of the through railway traffic of Chicago.--Cassier's Magazine. A Plea for Ship Protection. Hon. Wm. Rogers, ship builder of Bath, Me., sends the Review a copy of the Bath Independent of Nov. 27 containing an article, in which he makes a strong plea to the president and congress to stand by the Re- 'publican platform of protection for American shipping. !Mr. Rogers pre- sents some plain facts bearing on the shipping question. "T have enjoyed« reading in the Review," he says, "of the great strides that have been made in lake shipping. The progress which is so apparent 1n the industries bordering the shores of your immense inland waters is surprising to the people of the east. We do not realize their extent nor your resources. I[ have been a builder and owner of wooden ships for deep-sea transporta- tion for many years, and although endeavoring to keep progress in the race for that business, I confess we are far behind. Our coastwise trans- portation has maintained itself and grown in strength. There has been an innovation in that direction in the use of the 'barge,' which has evi- dently come to stay, even upon salt water. Reading in your Review and in other papers of the size iof steel barges on the lakes, 1 see no good reason why vessels should not be constructed here for 6,000-ton cargoes. We upon the coast feel highly gratified at the enthusiasm now expressed in favor of some strong measures being adopted by the government to build up our merchant marine. Your columns will have much influence toward it, and I hope you will keep up this good work." Ferrall's Sheaves. The illustrations herewith show a lignumyite sheave with six rolls and two galvanized iron sheaves with composition boxes for steel rolls to revolve in, one having five and the other six rolls. They are simple; the rolls are slotted in the center and run on an interior rail, having a separa- tor to keep them-apart. This sheave has the longest bearing on the pin of any sheave in the market, and the rolls cannot mill toward the center on account of the interior rail. Wire rope sheaves fitted with the Ferrall roll can be overhauled by one man, where two are usually required. The galvanized iron sheave is something new and will be in demand on the lakes and ocean, as it will not rust. The Bagnall-Loud Block Co.. Bos- ton, Mass, manufacture them. Some years ago, less than a score of firms were engaged in the manu- facture of piston packings. Of late years hundreds have engaged in the business, and every engineer knows that the market is flooded with all kinds of cheap packings. Many manufacturers of inferior packings have retired but some that are still in the market are not of the best. The great increase in the use of steam machinery with high speed and high pressures has created a demand for superior packings for pistons and plungers of engines and pumps and all kinds of hydraulic machinery, refrigerating ap- paratus, etc. One firm in this line, the Garlock company, has had a most cordial reception from the start, through its untiring efforts to serve its patrons faithfully with high grade packing of known reliability for quality, durability and economy. The name "Garlock" is recognized as the stan- dard of excellence by engineers in every country. Customers of this com- pany are numbered by the thousands. '"'Wherever civilization is found," says a circular from an eastern publishing concern, "we also find the steam engine and Garlock packings--the two go hand in hand in nearly every part of the globe." : The office of the Marine Review, Perry-Payne building, Cleveland, is the only place where a complete supply of lake charts of all kinds is con- stantly to be found. Every chart is corrected to date of issue, and the stock includes all publications of the hydrographic office, as well as the charts made by the army engineers corps. The vessel master who has charts published two or three years ago will find new ones of far greater value in the list that has been increased almost every week of late. Prices are those fixed by the government, which do not represent even the cost of paper and printing. Sets of sectional charts of places like Green bay and Georgian bay, which in time past have sold as high as $15, may now be had on a single sheet at 30 cents to $1. ; Senator James McMillan of Michigan has taken up the suggestion of Chicago naval reserve leaders and has introduced in the senate a bill pro- viding that the president be authorized to have constructed on the lakes a gunboat at.a cost of not more than $230,000, to replace the Michigan, This is in accordance with the recommendation made a few days ago by Assistant Secretary of the Navy Roosevelt in his report dealing with the naval reserves, and it is understood that Mr. McMillan will have the sup- port of the navy department for his bill. He is a member of the com- mittee on naval affairs and the bill will be referred to that committee. The announcement in Buffalo newspapers that the contract for a package freight steamer of the largest type, on which Manager Douglas of the Western Transit Co, has been figuring for some time past, has been given to the Detroit Dry Dock Co. cannot be verified as yet, but the facts will probably be given out in a day or two. The Buffalo report is uncer- tain for the reason that it was understood that two new steamers instead of one were under consideration.