Improved Means for Preventing Galvanic Action in Iron and Steel Ships when Protected by Copper or other like Sheathing, Applicable also to other like Submerged or PROVISIONAL SPECIFICATION. SHIPS WHEN PROTECTED BY COPPER OR OTHER LIKE SHEATHING APPLICABLE ALSO TO OTHER LIKE SUB- MERGED OR PARTIALLY SUBMERGED SURFACES to be as follows
Year: 1884

page_text: Improved Means for Preventing Galvanic Action in Iron
and Steel Ships when Protected by Copper or other like
Sheathing, Applicable also to other like Submerged or
PROVISIONAL SPECIFICATION.
I BENJAMIN LUMSDEN THOMSON of Gracechurch Street in the City of London
Merchant do hereby declare the nature of said Invention for "IMPROVED MEANS
FOR PREVENTING GALVANIC ACTION IN IRON AND STEEL SHIPS WHEN PROTECTED
BY COPPER OR OTHER LIKE SHEATHING APPLICABLE ALSO TO OTHER LIKE SUB-
MERGED OR PARTIALLY SUBMERGED SURFACES to be as follows :—
"
My Invention has for its object to prevent galvanic action taking place between
the iron or steel hulls of Ships or vessels or other submerged or partially submerged
metal surfaces and their metallic protective sheathing when the said sheathing
consists of copper yellow metal or the like.
In carrying out my Invention I apply to the iron or steel surface to be protected
a coating of vitreous material to which surface I affix the sheathing plates by
means of india rubber solution or otherwise. A layer of India rubber, or cork,
felt, paper or canvas or the like saturated with india rubber solution being
interposed between the sheathing plates and the surface of the metal to be
protected.
When the sheathing plates are socured in position I heat the vitreous covering
surrounding the edges of the plates by means of a blow pipe or otherwise so as to
cause the vitreous material to cover the joints and thus produce a perfect junction
which will prevent the entrance of water between the protecting plates and the
surface to be protected. By this means the galvanic action which takes place
between iron vessels and the copper or like sheathing plates as ordinarily applied is
entirely prevented.
I also propose in some cases to cover the surface of the sheathing plates next to
the surface to be protected with vitreous material.
DL: 10
1
1004

page_text: COMPLETE SPECIFICATION.
I, BENJAMIN LUMSDEN THOMSON of Gracechurch Street in the City of London
Merchant do hereby declare the nature of my invention for "IMPROVED MEANS
FOR PREVENTING GALVANIC ACTION IN IRON AND STEEL SHIPS WHEN PROTECTED
BY COPPER OR OTHER LIKE SHEATHING APPLICABLE ALSO TO OTHER LIKE SUB-
MERGED OR PARTIALLY SUBMERGED SURFACES and in what manner the same is to
be performed, to be particularly described and ascertained in and by the following
statement:
My Invention has for its object to prevent galvanic action taking place between
the iron or steel bulls of ships or vessels or other submerged or partially submerged
metal surfaces and their metallic protective sheathing when the said sheathing
consists of copper, yellow metal or the like.
In carrying out my Invention I apply to the iron or steel surface to be protected,
or part of it, a coating of vitreous material to which surface I affix the sheathing
plates by means of india rubber solution or otherwise. A layer of india rubber or
cork, felt, paper, or canvas, or the like saturated with india rubber solution is
preferably interposed between the sheathing plates, and the surface of the metal to
be protected.
When the sheathing plates are to be secured in position I can apply heat to the
vitreous covering surrounding the edges of the plates by means of a blow pipe or
otherwise so as to cause the vitreous material to cover the joints and thus produce
a perfect junction which will prevent the entrance of water between the protecting
plates and the surface to be protected. By this means the galvanic action which
takes place between iron vessels and the copper or like sheathing plates as
ordinarily applied is entirely prevented.
I also may with advantage in combination with the foregoing, cover the surface
of the sheathing plates, next to the surface to be protected, with vitreous materials.
The covering of the surface or part of the surface with vitreous material I
conveniently effect by preparing a solution of sodium silicate, or a paste formed by
moistening with spirit or other suitable liquid, materials, which when subjected to
the action of heat, will form glass and I apply this solution or paste to the surface
or parts of the surface to be covered with vitreous material, and I afterwards apply
heat by means of a blow-pipe or otherwise whereby the sodium silicate or glass
making materials are converted into glass, which thereby becomes efficiently
attached to the surface or the required part of the surface, and forms a secure
protection thereto. The action of heat may be resorted to either before or after
the plates are applied, if plates are to be used in combination with the vitreous
coating or covering effected as aforesaid.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed I declare that what
I claim is
First In protecting the bottoms of, iron and steel ships or other submerged or
partially submerged surfaces by means of yellow metal or copper or equivalent
sheathing first applying a vitreous coating to the surface or the parts of the surface
to be protected and then applying the sheathing plates thereto with or without
the intervention of India rubber or its equivalent substantially as hereinbefore
described.

page_text: Second-The protection of ships bottoms or other submerged or partially
submerged surfaces or parts of surfaces by applying a solution or paste of sodium
silicate or glass forming materials and then applying heat to convert the same into
glass substantially as hereinbefore described.
Dated this 10th day of December 1884.