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ONE of the latest developments in the bunkering of steamers is represented in the Herald a twin-screw coaling vessel shown in the photographs. The Herald is fitted on the Holland-Johnston system with two elevators, and has a speed through the water of 6 knots. The capacity of the vessel is 400 tons of coal, and the output 100 tons per hour per elevator, 1. e., 200 tons per hour for the vessel. Our frontispiece shows the Herald bunkeHng the London North-Western Railway Company's mail steamer Anglia and gives a clear idea of the construction of the vessel. The coal is carried in pockets or compartments on each side of the vessel. Between the compartments and extending nearly from one end of the coaler to the other, ls a longitudinal passage up and down which the movable elevators are free to travel. The system is novel and differs from other coaling methods, inasmuch as though the Herald has only two elevators, larger vessels fitted in the same way might have three, four or five elevators; and with each of these elevators, having an output of 100 tons per hour, it would be possible for a vessel so ftted to discharge herself at the rate of 500 tons per hour. Large ocean liners served by large vessels of the Herald type, one on either side of the liner, such as the Mauretania or Lusitania and the big vessels of the White Star Line, could thus be. coaled at the rate of 1,000 tons per hour. A thousand tons per hour may appear a very large quantity of coal to transfer from barge to steamer, and it can only be done by a system such as that on which the “Herald” is constructed, because to attempt to pass that quantity of coal down one shoot, or even two shoots, would mean that the discharge would have to be so rapid that the delivery of it could not properly be taken. In the “Herald” system, however, diferent shoots are put through the side bunker doors in diferent parts of the vessel and coaling is thus going on simultaneously in practically all parts of the vessel's bunkers, consequently, tbe only delay with this method will be at the fnal trimming in the top of the bunkers, which must always be a slow operation. The elevators may be moved from any one point in the trunk to another, being carried by the trucks on rails, which are shown in the photographs. In addition to this fexibility of the positions of the elevators, the barge itself can, of course, be moved, consequently there is no doubt that any vessel with side bunker doors may be coaled by this design of plant. When supplying coal to vessels provided with center bunker hatches instead of shoots, conveyors are put into operation for the purpose. With other systems of coaling a great drawback is experienced with the fne coal dust or dirt which gets blown about l,y the wind and covers the vessel being coaled from end to end with dirt. Compare these systems with the method of loading the London&North-Western Railway Company's mail steamer “Anglia,:' by the “Herald,” and it will be seen that the complete absence of dust in the case is remarkable. Coaling by means of the “Herald” is a very clean operation. No dust whatever gets on board the vessel being coaled. The elevators are driven by a very ingenious mulUpIe gear in the top pentagon drum; the small engine necessary for the purpose being contained at the head of the elevator between the top and the bottom trunks. The exhaust steam from this engine is admitted into the head of the elevator in a suitable position, and is directed along the shoots into the vessel's bunker doors. The illustration shows the steam. It was found by experience that coal dust is carried straight into the vessel's bunkers with the steam, thus insuring an extremely clean method of coaling steamers. It is stated that the steam does not in any way wet the coal. With two elevators, the crew of the “Herald” consists of the master, the engineer, the assistant engineer, a freman and three deck hands. This crew Is sufcient to navigate her and do all that is neces- sary in connection with the bunkering of steamers. The salient features claimed for this bunkering system are: Flexibilty as regards the shoots, cleanliness, rapidity and economy.