IMPROVEMENTS IN THE CONSTRUCTION OF SHIPS AND. VESSELS AND IN THE MODE OF PROPELLING THE SAME FOR RAPID TRANSIT ON WATER
Year: 1875

page_text: PROVISIONAL SPECIFICATION left by Claude Alphonse Jobert at the
Office of the Commissioners of Patents, with his Petition, on the
2nd July 1875.
I, CLAUDE ALPHONSE JOBERT, of Paris, Boulevard de Strasbourg,
No. 23, Engineer, do hereby déclare the nature of the said Invention
for "IMPROVEMENTS IN THE CONSTRUCTION OF SHIPS AND. VESSELS AND IN THE
MODE OF PROPELLING THE SAME FOR RAPID TRANSIT ON WATER," to be as
follows:-
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The object of my Invention is to obtain a very rapid propulsion of
boats and vessels upon smooth water. To attain this object I have
addressed myself first to discover the form of prow which would render
boats and vessels the more light, and which would encounter the least
resistance when passing through the water, and then to find a method
of propulsion which would most effectually apply the power employed,
and by copying the examples which nature affords by fish in their
movements through the water and by the insects which skim its surface,
I have succeeded in resolving the double problem.
I construct my boats preferably of iron or steel in a tapered form
similar to that of the eel or the insect called the hydrophile, so as to

page_text: reduce its transverse section in proportion to its length to the greatest
possible degree consistent with stability, which however I assure by the
arrangement of the propellers themselves, and by the addition of safety
floats which may be worked by hand or otherwise. The propellers I use
with these boats are formed of rectangular frames or boxes, partitioned
interiorly, and arranged longitudinally at each side of the boat. These
frames are animated with a movement which causes them to enter the
water and emerge therefrom while preserving their horizontal direction.
In the period of immersion acting like grapnels and similarly to the
claws of the hydrophile, these boxes embrace and retain a certain
amount of water, which being unable to escape affords them a support
The
more certain than is the case with the propellers hitherto in use.
fluid remaining almost without movement reacts upon the paddle board
which form the partitions, and renders to them almost entirely the
shock which it has received, from whence results a very complete
utilization of the force transmitted, and at the same time an impulse
always very regular in force and direction.
In certain cases instead of partitioned boxes I employ as propellers
for my boats paddle wheels provided with safety floats, which prevent
them from entering the water further than is necessary for their
effectual action therein.
The two kind of propellers just mentioned although different in
'arrangement yet both add to the stability of the boat, far from
lessening it they complete it and contribute much to render my boats
insubmergible and inversible. It is only in consequence of propellers
never having been found which would act with tapered forms that up
to the present time the enormous advantages which would result from
their use in ships of great speed have had to be foregone.
The screw less than all other propelling apparatus is capable of
adapting itself to tapering forms of vessels, because of the lateral efforts
of torsion which it necessarily exerts upon the boat and which greatly
contribute to make it capsize. The application of my propellers,
especially of tho grapnel box, puts an end therefore to the incom-
patability between the tapered form and propelling apparatus.