19I5| SUBMARINE Boats 123 
ship-shaped, and the superstructure was very long. The control of the 
motion in the vertical plane was never satisfactorily attained in the 
Nordenfelt boats. 
In France M. Claude Goubet experimented during the “eighties” and 
‘nineties’ with a small type of boat driven only by electricity derived 
from a battery of primary cells. He was entirely successful and his 
experience pioved of great value to later designers, but the boats were 
too small and slow to be of military value. The French Government, 
therefore, rejected his boats, and in 1886 set to work to build submarine 
boats itself. 
The first boat built by the French Government since its attempt 
with the Plongeur was the Gymnote, laid down in 1886, a small 30 ts. 
electrically-driven experimental submarine. As in the Goubet 
boats the power was at first derived from primary cells, but later a 
storage battery of iron-copper elements and finally of lead accumu- 
lators were substituted. Lead accumulators were here, it appears, 
used for the first time in submarine boats. 
In 1889 a much larger boat, the Gustave Zédé, $?{ts., was laid down 
She was likewise driven by electricity only and was designed for high 
speed. The ratio of length to diameter was about 15. Great diffi- 
culties were experienced with the storage battery. On one occasion 
the battery was so badly damaged by short-circuiting that it had to 
be dismantled, whereupon larger cells of an improved type were sub- 
stituted. Vertical steering proved very difficult, the boat often took 
excessive inclinations and hit the bottom on some occasions. Additional 
horizontal rudders were fitted, so that at last there were rudders both 
forward and aft and also amidships. 
The construction of the next boat the Morse was suspended for a 
long time pending the alterations in the Gustave Zédé and was not 
completed till 1898. The Morse was more ship-shaped and carried an 
optical tube, probably of primitive construction. This was a most 
important addition to the outfit of the submarine boat, because if further 
developed it promised to solve, partly at least, one of the greatest 
difficulties connected with submarine navigation, viz., the complete 
blindness of the boat when travelling under water. It enabled a boat 
to approach an enemy within striking distance of the torpedo without 
the necessity of coming to the surface, showing at intervals only the 
head of the periscope a few feet above the water. 
In 1899 was launched the Narval, }$3ts., designed by M. Laubeuf, a 
French naval constructor. This boat represents in an eminent degree 
the type referred to before as a ‘‘submersible”’, which term was first 
introduced by M. Laubeuf to distinguish between his ship-shaped boat 
