Dudgeon v Thomson

GEORGE TOMLINSON BOUSFIELD, of Loughborough Park, obtained letters-patent, dated 7th March 1866, sealed 13th July 1866, for ‘improvements in apparatus used in expanding boiler tubes, a communication from abroad by Richard Dudgeon, residing at New York, United States of America.’ This patent was assigned to Mr Dudgeon in 1872. This invention was stated in the complete specification to be ‘to enable the ends of boiler tubes to be expanded in the holes in the flue-sheet. Previous to this invention it has been customary to expand the ends of tubes by an expanding tool, composed substantially of a series of swages radiating from a common centre, and caused to diverge by means of a tapering plug driven into the centre of the tool by the repeated blows of a maul or sledge. The principle of the invention, which constitutes the subject-matter of this patent, is to expand the tube by rolling the metal, by the application of one or more pressure-rollers to the interior of the tube, so that the metal is expanded by rolling, in contradistinction to the old system of driving it outwards by hammering, and as the roller can be operated by hand, the use of mauls or sledges, and fill the inconveniences that attend their employment, are dispensed with.’

After describing in detail various methods of constructing the roller-expanding tool invented by the complainer, the specification proceeded,—’Although a tapering or wedge-formed plug is preferred as the expanding instrument, the invention is not limited to an expanding instrument of that form, as circumstances may render expedient the use of an expanding instrument of different form—thus, when a tool is sufficiently large an arrangement of toggle-jointed levers may be inserted in it for the purpose of expanding the roller in place of a tapering plug.’ The specification then concludes thus:—’In all the above-described modifications of the roller expanding tool, at least one roller is combined with a tapering plug (or its equivalent, by whose action the roller is forced outwards in the tube), and with a stock or holder by which the roller is prevented from twisting sidewise as it is turned round in the tube. These three instrumentalities are all that are absolutely essential to the construction of the roller expanding tool, but the cutter and ratchet handle constitute, with the said instrumentalities or implements, useful combinations which are supplementary to the aforesaid fundamental combination. What is claimed, therefore, as the invention to be secured by letters-patent is, the combination in an expanding tool of the following implements, viz., the roller, roller-stock, and expanding instrument,—these three operating in combination substantially as set forth. Also the combination in an expanding tool of the following implements, viz., the roller, roller-stock, expanding instrument, and cutter for trimming the tube, all operating in combination substantially as set forth. Also the combination in an expanding tool of the following implements, viz., the roller, roller-stock, cutter, and a ratchet handle for turning it, all operating in combination substantially as set forth.’

Mr Dudgeon presented a petition for interdict against William Thomson, engineer in Glasgow, from infringing the letters-patent by making, vending, or using, in whole or in part, the improvements in apparatus used in expanding boiler tubes, described in the specification filed on 30th August 1866, in pursuance of the proviso contained in the said letters-patent, and, in particular, from making, vending, or using any apparatus for expanding boiler tubes constructed or used in the manner described in the said specification, or in manner substantially the same, and from infringing the said letters-patent in any other manner of way.

The respondent had obtained letters-patent for a similar invention dated 18th August 1868, and sealed 16th February 1869. He stated in his defences that this invention was novel and original in various particulars, and that the tube expanders made and sold by him under his own letters-patent were in principle and in all material respects different from those alleged to be protected by the complainers' letters-patent. He specified the particulars in which they differed; and averred further;—’In the provisional specification of the complainers' letters-patent the alleged invention was declared to be for “improvements on apparatus used in expanding boiler tubes,” and the advertisements of said application so described the nature of said alleged invention. But this title was misleading, and did not sufficiently disclose the true nature of the invention claimed, which, in addition to being an apparatus for expanding boiler tubes, also claims to be a cutter for trimming boiler tubes, besides other combinations and purposes. The title of the patent and its nature were thus inconsistent with and disconform to each other. The final specification founded on by the complainers further sets forth that by means of the alleged invention “the use of mauls and sledges, and all inconveniences that attend their employment, are dispensed with.” In practical operation, it has been found that the alleged invention cannot effect the object alleged to be accomplished by it without, either, first, the use of mauls or sledges or hammers, as a means of forcing in the expanding plug, with which any other mode of forcing in the same would be inadequate to accomplish these results, and no other means of forcing it in are provided; or, second, by the boiler-makers attaching a rod to the inner end of the tapering plug, and pulling it inwards by the help of a screw and nut in the further end of the rod which projects out of the opposite end of the tube; but this is a mode of operation wholly different from any described in the specification founded on by the complainers. There was thus a misrepresentation and failure to make a full and true disclosure of what was necessary to render the alleged invention effectual, or to enable a workman of ordinary skill to put the same into practice.’

The complainers pleaded;—The respondent having infringed the complainers' said patent rights, as above condescended on, and having refused to discontinue said infringement, the complainers are entitled to have interdict as craved.

The respondent pleaded, inter alia;—3. The suspension and interdict ought to be refused, as the letters-patent founded on by the complainers are invalid, in respect—(1) of the disconformity of the provisional specification with the letters-patent and final specification; (2) of the misrepresentation in the final specification above stated; and, (3) of the failure in the said specification to make a full and true disclosure of the invention, such as would enable a workman of ordinary skill to put the same into practice. 4. The suspension ought also to be refused, in respect the respondent has not infringed the letters-patent founded on by the complainers.

The Lord Ordinary allowed a proof, the import of which is given in his Lordship's note and the judgment of the Lord President.

The Lord Ordinary pronounced the following interlocutor:—’The Lord Ordinary having heard the counsel for the parties, and considered the closed record, proof, and process, sustains the reasons of suspension, suspends, prohibits, interdicts, and discharges in terms of the note of suspension and interdict, and decerns: Finds the respondent liable in expenses, of which allows an account to be given in, and remits,’ &c.∗

The respondent reclaimed, and argued;—The complainer's letters-patent were invalid, in respect of the disconformity between the title and provisional specification, and the final specification.1 The final specification also misrepresented the invention, and failed to give such

The complainer argued;—There was no material variance between the title and provisional specification and the complete specification. The provisional specification was intended to describe generally and fairly the nature of the invention without detail;2 and it could not, after being allowed by the law...