(The original description was written in 1899 and is in the handwriting of Engineer Charles A. Morris. It is located in the Morris Collection, Submarine Library, Groton CT.)
"She is 53.3 feet overall, largest diameter is 10.3 feet; draft in cruising position, 8.5 feet; draft in a diving position, 11.5 feet; 63 tons light displacement and 75 tons submerged. Her speed varies from 6 to 10 knots according to power used. The radius of action with gasoline alone is 1300 knots, with gasoline and electricity, 1330 knots, allowing 30 knots for electricity. The air reservoirs contain 30 cu. ft. of air at 2000 lbs. per square inch.
The hull is parabolic, spindle-shape. It is constructed of steel plating; the frames are of angle iron which are all perfect circles, the largest being 10.25 feet placed a little forward of amidships, tapering to both ends and all set up from a center line through the ship. This construction will resist a pressure of 35 lbs. per square inch, which is sufficient to allow her to dive to a depth of 75 feet.
She is fitted with 5 tanks placed along her bottom, the fuel tank having a capacity of 1000 gallons, the sinking and trimming tanks 10.5 tons capacity.
The boat has a 45 H.P. Otto Gas Engine connected so as to drive the propeller or dynamotor for charging the batteries. The dynamotor can also be connected to drive the propeller. These connections are made by friction clutches. The dynamotor is connected to run at any speed or power from 10 H.P. to 150 H.P.
The batteries are placed amidship, occupying a space 15 ft. long by 6.25 ft. wide and 3 feet deep, have 60 cells and a capacity of 1500 ampere hours. There is an extra 10-horse electric motor which operates the bilge pump and air compressor. The bilge pump is piped so as to empty or fill all tanks independently, or to pump out the bilge. The compressor is capable of compressing 50 cu. ft. at 2000 lbs. pressure per hour. There is also a 1/8 H.P. electric motor for ventilating and operating an exhaust pump for exhausting the air from the vessel when making long submerged runs, atmospheric pressure being maintained within the vessel by this pump together with a special valve which admits air into the vessel from receivers when pressure falls below atmosphere. The air is stored in three pairs of reservoirs at 2000 lbs. per sq. in. and by pressure regulating valve reduced to 50 lb., then another pressure regulating valve reduces to 10 lbs. pressure to the square inch, from which the atmospheric valve operates. The 50-lb. tank supplies the expulsion tube, steering gear, whistle, and trimming tank; the 10 lb. tank operates the sinking tanks and atmospheric valve. The steering engine is controlled by hand from the turret or automatically by a vane placed aft over the rudder; it is connected by a rod running aft through a stuffing-box to the rudder which is balanced and placed above and below the propeller, a second rod connects the vane to a valve on the steering engine.
The diving engine is controlled by hand from the turret or automatically by diaphragms operated by the water pressure together with the pendulum and springs connected by a rod through a stuffing-box to two diving rudders placed on either side of the propeller at right angles to the steering rudder.
A regulation Whitehead torpedo tube is fitted in her bow at the center and is discharged by air through a special valve for the purpose. The Whitehead torpedoes are shipped through the tube into the boat; i.e.,, the outer door is opened, the torpedo inserted into the tube from the outside, the door is then closed, the water discharged from the tube, the inner door opened, and the torpedo hauled in and placed into a rack. Provision for two of these torpedoes has been made in the boat and one may be left in the tube, making three in all. A special crate or cage has been designed for loading the torpedoes, which eliminates all risk, making it possible to supply the "Holland" from a tender in any harbor.
Directly above this expulsion tube is placed the Holland Pneumatic Dynamite Gun of 8.425 inches bore, having a fixed elevation of 15 degrees, but by filling or emptying the trim tanks this can be increased or decreased. The muzzle of gun is fitted with a water-tight cap. It will discharge a projectile of 222 lbs. weight, charged with a 50 to 80 lbs. gun cotton, giving a range in the air of 1000 yards or 30 yards when fired under water. It is operated by air and gun-powder and is quickly handled. Six or more of these projectiles can be carried. [Formerly, "Holland" had two such guns, but the after gun was removed.]
She is fitted with a sounding apparatus, speed indicator, and all necessary gauges, controllers and regulators; is completely lighted by electricity, has a water-closet; and a crew of 6 men can comfortably live aboard for 40 hours.
The turret is where the commander or operator is located; it is fitted with a hinged manhole cover 24-inches in diameter, through which entrance to the boat is obtained. The turret is fitted with thick plate glass windows 3 inches long by 3/4 in. high, arranged all round so that the commander has an all around view.
The is a spirit compass, a pressure gauge, which indicates the exact depth at which the boat is traveling; bell pulls for starting and stopping; two speaking tubes; whistle pull; indicators for showing position of both rudders, together with two controllers for the steering engine. Gauges, compass and indicators are lighted by covered electric lights. Three glass windows 1-inch in diameter are fitted in the cover to turret; these are used to indicate when passing under a vessel.
The crew consists of a commander, assistant-commander, electrician, engineer, gunner, and machinist who acts as assistant-gunner."
Morris, R.K., John P. Holland: Inventor of the Modern Submarine. (Annapolis: U.S. Naval Institute, 1966; 2nd ed., Univ. S.C. Press, 1998) pp. 181-182.