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C-14 / PG-28 / CL-16 Denver

USS Denver (Cruiser # 14, later PG-28 and CL-16) was the name ship of a class of six 3200-ton protected cruisers, also known as peace cruisers. An Armored Cruiser was the old pre-Washington Treaty term for a first class cruiser, a Protected Cruiser being a second class cruiser. An Armored or First Class cruiser had larger guns and better armor than a Protected or Second Class Cruiser. Then there was the Third Class Cruiser - the USN Peace Cruiser - a fancy name for a gunboat assigned to foreign stations, typically in asiatic waters).

These vessels were like British small second-class cruisers ; but they are nominally 3 knots slower on trial, and do not seem to be any improvement upon UK vessels. There were no vessels in the United States Navy of a class similar to the British third-class cruisers ; but there had been built, since 1891, nine gunboats of 1,000 to 1,300 tons, and of 13 to 15 knots speed. They have no protection, their principal armament being six 4 in. guns. They had a very limited amount of subdivision, and can hardly be looked upon as war vessels of much power, but act as good training ships.

Six ships in this class of "peace cruisers" featuring endurance over armament and protection. The ship's hull was sheathed with pine and coppered at and below the waterline for long service in tropical waters, to reduce the need for drydocking while operating on distant stations. This class of cruisers, consisting of six vessels, constitute the only sheathed vessels in the U. S. Service, except the Severn; they are sheathed with wood, and coppered, to permit of service on foreign stations without the necessity for frequent dockings, which is necessary with unsheathed steel ships.By this means is provided a ship structurally as strong as a steel ship, with the advantage of copper sheathing. It is essential that there should be insulation between the copper: and the steel skin. In foreign services it was formerly the practice to fit the wood sheathing in two thicknesses, but this has since been abandoned in foreign services for the sheathing in on thickness, which is the method that has always been adopted the U. S. Service.

In the Denver class, to prevent corrosion from galvanic action between copper sheathing and steel, a bronze stem is fitted, Manganese bronze is employed for this purpose on account of its physical qualities. In the sheathed ships of the Denver class, the stern-posts are of bronze, as are the stems.

It was early found that iron and steel vessels required unusual care hi the preservation of the hull, iron and steel immersed in sea, water being subject to rapid corrosion. The British service built a number of steel vessels sheathed with wood so that they may be coppered. By around 1900 the US had in service several composite gunboats, i. e., steel frames with wood planking instead of plating, but only one class (Denver class) of six ships sheathed and coppered. The British and other foreign services seemed to be working away from the practice of building sheathed ships, which were more expensive in first cost, and less speedy. With an unsheathed ship the only method of preventing fouling by marine growth was by docking and painting at reasonable intervals.

The ships of the Denver class are 3,200 tons displacement, steam 16 knots. Length of load water line, 92 ft. ; length, extreme, 308 ft. 2 in. ; breadth, extreme, about 43 ft. ; mean draught at trial displacement, with two-thirds coal, ammunition, and stores, 15 ft. 6 in. ; extreme draught, fully loaded, 16 ft. 8 in. ; trial displacement, about 3,100 tons; full load displacement, about 3,400 tons ;

The coal carried on trial, 470 tons ; total bunker capacity, not less than 700 tons. The coal capacity of these ship with bunkers full (700 tons) is sufficient to give them a radius, of action at full speed of about 2,600 miles. At the most economical rate of steaming, probably in the neighbourhood of 10 knots, they would be able to steam about 9,860 mile without recoaling, or more than sufficient to take them from San Francisco to Manilla.

The engines are of the four-crank triple-expansion type. The main engines, of which there are two sets, each driving a propeller, are of the vertical inverted cylinder direct-acting triple-expansion type, having cylinders: - High-pressure 18 in. diameter, intermediate-pressure 29 in,, and two low pressure 53-1/2 in. diameter, 30 in. stroke. The I.H.P. of the combined engines is to be 4,500 when the engines are making 172 revolutions per minute, with a boiler pressure of 275 Ibs. reduced to 250 Ibs. at the high-pressure cylinder.

All ships in this class were remarkably good sea boats. They had no side armor, but have each a protective deck, 2 in. on the slope, in. on the flat. The protective deck, coal, and cofferdams furnish all the protection. The inner bottom is retained, but is somewhat less in extent than before, being over about two-thirds of length, under magazine, engine, and boiler spaces. The inner bottom extends to the bilge on either side, as in the case of large cruisers, but there is no wing bulkhead, the coal bunker extending to the shell. The vertical keel is continuous, 34 inches deep, of 15 Ibs., with double angles at top. The wood material used in the construction of the hulls will be reduced to a minimum. All the bulkheads on the gun and berth decks will be of metal, and they were each be fitted with a pilot house on the spar deck built entirely of non-magnetic metal.

The armament consisted of ten 5-in. breechloading rapid-firing guns, eight 6-pounder, two 1-pounder rapid-firing guns, and four Colt machine guns. The 5-in. guns were more effective than the old type. Eight of them were mounted on the main deck in recessed ports. The two remaining 5-in. guns were mounted behind shields on the spar deck, one forward and one aft. Four 6-pounders were mounted on the main deck, two forward and two amidships, and four more on the spar deck. The two 1-pounder guns were mounted aft on the main deck, and the Colt machine guns on the top of the hammock berthing amidships. The ammunition supply was large. For each of the 5-in. guns they carried 260 rounds, and for each of the 6-pounders 500 rounds.

Construction problems caused Denver to be towed to Norfolk for completion at the Navy Yard. Work was commenced late in the year 1899 on the Cleveland, and which took her place in Uncle Sam's sea patrol in 1903. The Cleveland was a two masted schooner-rigged cruiser, and was constructed at Bath, Maine, famous as the home of the American clipper ship. She was 292 feet in length, a trifle less than the Cincinnati, but was two feet broader; and, although she had a displacement of 3,200 tons, or somewhat more than the Cincinnati, she can enter ports having a depth of water two feet or more short of that required to float the latter.

The handsome man of war that bears the name of the Forest City, was not especially speedy, having made a record, on trial, of only about nineteen miles per hour, but she was a most servicable type of craft, as was eloquently attested by her record in West Indian waters. The armament of the Cleveland is almost identical with that of the Cincinnati, save that the newer ship has ten instead of eleven of the five-inch guns and a couple of additional automatic guns.

The namesake of the Western Reserve metropolis is a member of a rather numerous naval family, having as sister ships, the cruiser Denver, Des Moines, Galveston. Chattanooga, and Tacoma. Four of them are named after trans-Mississippi cities. They are besides the Denver, the Galveston, the Tocoma, the Des Moines, the Cleveland and the Chattanooga. These six are a type less than the Colorado and her companions, costing $1,080,000 and having a speed of seventeen knots per hour.

The full report of the tests made under auspices of the United States Navy to determine the relative efficiency of coal and crude petroleum as fuel was released in late 1904. The experiments were made with a water tube boiler of the kind which has been adopted for cruisers of the Denver class. An inquiry equally thorough had never before been made in this country, and much of the information secured was serviceable to railroad companies, owners of merchant steamers and persons who meditate the establishment of power plants either for the generation of electricity or for manufacturing purposes. The relative merits of a variety of burners were also examined by the government, and the results obtained increase the practical value of the report. Coal was used in seventeen and oil in sixty-nine. The average amount of water evaporated by a pound of coal was nine pounds, while twelve and a half pounds were evaporated by the same quantity of petroleum. Weight for weight, then, the latter showed a superiority of about 40 per cent. It should be added that Pocahontas coal and Beaumont oil were employed in these tests. Had either the solid or liquid fuel been of another quality, of course, the ratio would have been different.

They were reclassified as gunboats (PG) in 1920. In 1921 they were again reclassified as light cruisers (CL).



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