Major Modifications
Winter of 1898-1899

H6-18-Before Photo

Propeller Aft of Rudders

The Morris Collection

H6-23-After Photo

Propeller Forward of Rudders

The Morris Collection

Tank Arrangement
Tank Arrangement

Drawing by Gary McCue

In his book John P. Holland: Inventor of the Modern Submarine, Richard K. Morris described the modifications made during the winter of 1898 - 1899 as follows:

"The extensive remodeling of the Holland VI progressed slowly through the winter of 1898-99. Bitter cold weather, faulty workmanship, hasty installation of inadequately tested equipment these were some of the factors responsible for prolonging the work schedule set by the Holland Torpedo Boat Company. When the calendar showed that spring had arrived, the Harlem River remained jammed with ice, further delaying an early launching of the submarine."
"In spite of these frustrations, the overhaul resulted in an improved arrangement of machinery on board the boat. The after dynamite gun was removed to provide space for an improved exhaust system for the gasoline engine. Two new after trimming tanks were fitted in the hull on either side of the propeller shaft. A series of small compensating tanks were added to take care of weight lost in the operation of the vessel. The use of these small tanks in conjunction with the trimming tanks did not present the dangers inherent in the practice of partially filling the large ballast tanks and then admitting water to bring about the required trim. Frank Cable had suggested this practice, but Holland always insisted that water allowed to surge about in the larger tanks could suddenly alter the center of gravity and produce disastrous results."
"The major reconstruction entailed shortening of the porpoise-shaped hull at the stern, moving the propeller forward, and constructing a heavy skeg to which was tied, by a circular loop, three struts of angle iron to support the rudders and diving planes abaft the propeller. The automatic steering vane, in its v-shaped channel, was remounted on the upper rudder brace. This return to the conventional position of the propeller and rudders was the answer to the complaint of naval inspectors that the Holland VI yawed uncontrollably when running submerged."1
  1. Morris, Richard K., John P. Holland: Inventor of the Modern Submarine. (Annapolis: U.S. Naval Institute, 1966; 2nd ed., Univ. S.C. Press, 1998), p. 95.

Copyright 1999,2000,2001,2002 Gary McCue