Howard Irving Chapelle

“ The boilers were in the hold, but Marestier gives no dimensions. However, he comments that, in American steamers, the space for steam in the boilers varied from 6 to 12 times the capacity of the cylinder. He gives the Savannah's boiler pressure as 2 to 5 pounds per square inch and the maximum revolution of the wheels as 16 revolutions per minute. The boilers could burn coal or wood. Judging by Marestier's sketch of the ship, the stack was at the firebox end; the boiler or boilers were underneath the engine. ”

“ However, fuel space is affected and, with double boilers, the cross-sections of the bunkers are reduced to about 20 square feet each; therefore, the bunkers would have to become much longer. It may be said that the boiler capacities in relation to dimensions of the steam cylinder as indicated in the Russian description far exceed those given by Marestier. As a practical matter of ship design, it seems that the single boiler would have been a more logical fitting than double boilers. The boilers were apparently of copper, and expensive. ”

“ All requirements that have been given can be approximated for space necessary in the hull. It is established that the ship carried about 75 tons of coal and 25 cords of wood. The coal would take up from about 1,700 to 1,850 cubic feet of space, and because of its weight it would have to be bunkered alongside the boilers in the lower hold, where there would be ample room, in the reconstruction, for two bunkers, each in excess of 30 square feet in cross section and about 28 feet in length for a single boiler; one third more bunker space, in length, would be required for double boilers. ”

“ From the valve chest the melted tallow was carried into the cylinder, and from there probably passed into the jet condenser. No doubt the lubricant became a sludge that had to be removed from the condenser at least once every 48 hours. There is no real evidence that the engine and boilers suffered any great strains; the operating pressure of steam must have been low at all times. The boilers were probably of very low efficiency and made steam slowly. Fuel consumption was high, and, according to the logbook, the vessel ran out of coal when she reached the English coast ”

“ Plans of the ship, or a builder's half-model, have not been found. Marestier's sketch of the Savannah, which is not a scale drawing, and his drawings of the engine and paddle wheels were the only available illustrations upon which reconstruction could be based. ”

“ The old, inaccurate model, built to the scale of one-half inch to the foot, represents an auxiliary, side-wheel, ship-rigged steamer. The model scale measurements are about 120 feet in over-all length, 29 feet in beam, and 13 feet 6 inches depth in hold. The tonnage is stated on the exhibit card to have been about 350 tons, old measurement. The model has crude wooden side paddles of the radial type, a tall straight smokestack between fore and main masts, a small deckhouse forward of the stack, a raised quarter-deck, and a round stern. ”

“ The steam inlet and outlet pipes enter a valve chest on top of the steam cylinder, which is described as being 1.035 meters (3.4 feet) in diameter, and of 1.5 meters (4.9 feet) in stroke.
The paddle wheels are shown as being of iron, with two fixed arms opposite one another on the hub. The other arms (four above and four below the fixed arms) are pivoted to the hub and held spread by chain stays. These eight blades fold, in pairs, to each of the fixed arms. The wheels are shown in elevation, with the upper pivoted arms folded on top of the fixed arms, and in cross section ”

“ This work resulted in information as to how the side wheels were folded, the dimensions of the boilers, and some description of the cabins and fittings.
As to the ship itself, the customhouse registered dimensions are of prime importance; they fix the over-all hull dimensions within reasonable limits. A vessel of 1818 measuring 98 feet 6 inches between perpendiculars would have been 100 to 104 feet long at rail. The type of ship represented by the Savannah is well established. All references are in agreement that she was built as a packet ship—a Havre or transatlantic packet in most accounts. ”

“ Cabin stores would have been in the hold below the passenger accommodation, and here food, water, and other stores would have been kept. A small cargo space, say of about 1,500 to 2,500 cubic feet, depending on bunkers, would have been possible in the after hold. A fore cargo hold of about 1,000 to 1,500 cubic feet of contents could be expected; forward of this would have been sail locker, spare rigging gear, and a cable tier. On the lower deck, above these spaces, a forecastle might have had berths for 12 to 14 men. ”

“ At sea the boat was probably carried on top of the deckhouse. The vessel obtained a new boat during her European trip. It is probable that the lack of passengers is why a second boat, which could have been stowed on the deckhouse roof, was omitted. ”