1

principle, however, remaining the same; that is to say, one side of the prism is considerably inclined, and the other, which faces the room, is vertical, or nearly so, by which arrangement the larger proportion of the light is directed into the room.

"The form shewn in Figs. 2 to 6 throws the light more directly forward than the form shewn by Fig. 7."

Fig. 8 shewed a glass which is rectangular on the face, but in other respects was similar to that shown at Figs. 2 to 6.

"What I claim is the construction of pavement lights substantially as described."

It was proved at the trial that at the date of the patent it was not a new thing to use a prism for the purpose of reflecting light. The light entered one side, struck another side at an acute angle, and being reflected completely or nearly so, issued from another side in the direction required. But no application of this principle had previously been made to pavement lights. One anticipation alleged was the use by a skilled optician of prisms in a similar manner to receive a beam of light through an opening in a shutter of a darkened room.

On an appeal for a new trial.

Held, that on the true construction of the specification the claim was for a combination of old things-the metal frame of a pavement light, the flanges thereon, and the prism to produce the new pavement light-and that there was sufficient ingenuity to support the patent.

Bramwell, L.J. (p. 116): "I think the plaintiff is an inventor. I think he has found out and manufactured and patented a thing, an article, namely, a light directing pavement light. I do not think there is any very great quantity of invention in it; it is not as though a man had sat himself down to consider how he could make a sewing machine, or a grass-pressing machine; it is a much humbler piece of invention than that, and it may possibly be nothing more than that the idea struck him, and immediately the idea struck him he could apply it or carry it into execution by a very obvious apparatus. But still it is an invention, and it is not the less an invention because it required but small inventive powers to enable him to do it. One may take an illustration in this way—the screw propellers. I suppose everybody knew that a screw, used as it was, would act in the way a screw propeller does; but the man who thought of it and applied it to a steamboat, which I suppose anybody could have done if the idea suggested itself to him, would have been called the inventor of a screw propeller or screw-propelling steamboat, as the case may be. It does not depend upon the quantity of the invention. Nor is it in this case the patenting of an idea. He does not say, 'I thought of such and such a thing, and I claim a patent for it;' but he says, 'I have thought of such a thing, and I will show you how to carry it into execution,' and therefore it is not open to any objection such as I have indicated; nor is it open to any objection in

It is unnecessary to reproduce this modification

regard to the constituent parts being old. No doubt the prism, as the plaintiff uses it, is old; it is as old as the world that a prism used as the plaintiff uses it will direct light in the way his prism does, and the other part of his invention is not new, that is to say, the particular mode in which he makes his pavement light, but the combination is a novelty.1

"The thing was never practised before, and undoubtedly a combination of two old things may be made the subject of a patent. It seems to me that the plaintiff really is an inventor-he has found out something. He makes an article that was not made before. This particular case may be, no doubt, upon the verge; but one cannot help making this remark, that it is very strange if it is no invention that it has never been done before. Why has it never been done before? Why, because nobody else found it out, which I take to be equivalent to inventing, and I think, therefore, that his patent is sustainable." 2

Brett, L.J. (p. 121): "In all previous cases it had been taken for granted that if the thing were new and useful, there must have been invention in order to arrive at a thing that can be so described, and I should say that in 999 cases out of 1000 that must be so. I say, if the thing is new and useful, it is impossible to suppose there is not sufficient to make an invention, but I do not think, as a matter of law, that could be predicated as an absolute rule of law. . . . I think this machine is invented by the plaintiff and claimed by him as a new machine combined of old parts, or apparatus, or commercial article, whichever you please to call it, is new, that it is claimed as new, and therefore it is the subject-matter of a patent.” ♦

Notes.

This case has frequently been referred to as an example of the smallness of the amount of ingenuity necessary to support a patent (e.g. Brereton v. Richardson, 1 R. P. C. 168), and to shew that although very little may do, still there must be ingenuity involved: Cotton, L.J., in American Braided Wire Co. v. Thomson, 5 R. P. C. 123; Lopes, L.J., in Blakey v. Latham, 6 R. P. C. 189; Cotton, L.J., in Williams v. Nye, 7 R. P. C. 67; and Lindley, L.J., in Gadd v. Mayor of Manchester, 9 R. P. C. 524.

[The main feature distinguishing this pavement light from the old ones used in ships' decks consisted in the application of the principle of internal reflection of light. In the diagram here given AB represents a section of a surface common to two media, both of which are transparent. One of these (marked D) is the denser, and the other (marked R) is the rarer; eg. D might represent glass or water, and R air. If a ray of light from the rarer

1 This paragraph was quoted and followed by Byrne, J., in Reason Mfg. Co., Ltd. v. E. F. Moy, Ltd., 19 R. P. C. 416.

2 This second paragraph was followed by O'Brien, C.J., in Pirrie v. York St. Flax Co., II R. P. C. 437.

* Quoted by FitzGibbon, L.J. (ibid., p. 450).

• Quoted and followed by Kennedy, J., in Ducketts v. Whitehead, 12 R. P. C. 191.

medium travel along xO it will not continue along in the same direction Oy, but be bent from the common surface AB, say along Oz. The amount of this change of direction depends

on the coefficient of refraction

of one medium as regards the other, that is, it depends on the relative velocities of light in the two media. Conversely, a ray of light travelling along zO will continue in part along Ox, and part reflected along Oz1, Oz1 and Oz making equal angles with AB. But a ray of light falling nearly along AO, in the rarer medium, will be bent along OC; no light reaching O from

the rarer medium can pass

along OE, that is, in the Sketches of refracting and reflecting prisms. FGH,

angle BOC. This angle is the "critical angle" for the

section of deck prism. KMN, section of reflecting prism.

two media. Conversely all light-rays reaching O from the angle BOC, as, for instance, along EO, are altogether reflected along OE1, rays along E1O being totally reflected along OE. The eye placed at E cannot therefore see through the apparently transparent surface OA, but that surface appears as a reflector. For example, by placing the eye slightly below the level of the surface of water in a tumbler, it will appear like the surface of mercury.

In the older pavement lights the prisms were shaped somewhat like FGH, FG being the surface; the light was distributed by refraction, but not reflection, rays entering along zO being refracted into the room below along Ox, the portion reflected along Oz1 being useless. In the sketch here given, KMN, a ray along 20 is totally reflected along Oz1 and emerges into the room (after refraction) along z'w. Hayward's prisms are so shaped that the sides marked a' act as perfect reflectors to all light-waves falling on them through the glass and within the critical angle for glass and air. But if the rays be outside that angle the greater part will still be reflected at the surfaces a1.]

1882. UNITED TELEPHONE Co. v. HARRISON & Co., 21 Ch. D. 720.

Disconformity-Publication.

This was an action to restrain infringement of two patents, Edison's (No. 2909 of 1887), for "improvements in instruments for controlling by sound the transmission of electric currents, and the reproduction of

corresponding sounds at a distance," and the other, Brown's (No. 4765 of 1876), for "improvements in electro-telephony."

The former described in outline the invention in the provisional specification. Before drafting the complete Edison discovered the phonograph. The complete specification as amended had three claims: one for the mica diaphragm, the second for the combination of that diaphragm with "electric tension regulators," and the third for "the method herein specified of recording the undulations of the diaphragm or yielding material, and the reproduction of sound by such material acting upon a diaphragm to communicate to the same, vibrations similar to the original ones, substantially as set forth."

The objection raised to this specification was that of disconformity. The provisional specification described electrical arrangements, whereas the phonograph as claimed in the third claim had nothing to say to electricity.

An objection raised to Brown's patent was that it had been previously known and published in England under the following circumstances. A description of Reis's telephone was published in a German periodical in Berlin in 1862. This work was in the library of the Institute of Civil Engineers for seventeen or eighteen years before the date of the patent. This library was open to all members, of whom there were 1000 in 1864, and at a subsequent time 3000. The publication was entered in the catalogue only under the head "Journals." A witness proved that he saw the journal in question in 1876 in the Patent Office Library, and from his knowledge of technical terms and the drawings could (although ignorant of German) understand the invention therein described.

Held, (1) that the Edison patent was invalid, the phonograph not having been disclosed in the provisional specification; and (2) that, the description of Reis's telephone was "published" in England under the above circumstances.

Notes.

This case has been frequently referred to as an example of a patent being invalid on account of "disconformity": Horrocks v. Stubbs, 3 R. P. C. 233; Moseley v. Victoria Rubber Co., 4 R. P. C. 248; Pneumatic Tyre Co. v. E. London Rubber Co., 14 R. P. C. 98. It was quoted as illustrating the correct mode of testing disconformity, namely, to read the complete first, and then the provisional, to find if invention is there: Siddell v. Vickers, 5 R. P. C. 98, 99; and Gadd v. Mayor of Manchester, 9 R. P. C. 260.

It is also an example of the rule that the question of " publication" is an inference from the facts proved in each case: Harris v. Rothwell, 3 R. P. C. 387. Publication to one person in this case being sufficient : Lindley, L.J., and Lopes, L.J., in same case on appeal, 4 R. P. C. 231, 233.

1882. OTTO v. LINFORD, 46 L. T. 35.

Principle-Construction-Inventive Ingenuity--Combination-Sufficiency—

Paper Anticipation.

In 1876 a patent (No. 2081) was granted to C. D. Abel for an invention (communicated from Dr. Otto abroad) for improvements in gas motor-engines.

The specification was as follows1:

"In gas motor-engines as at present constructed, an explosive mixture. of combustible gas and air is introduced into the engine cylinder, where it is ignited, resulting in a sudden expansion of the gases and development of heat, a great portion of which is lost by absorption unless special provisions are made for allowing the gases to expand very rapidly.

"According to the present invention combustible mixture of gas or vapour and air is introduced into the cylinder together with air or other gas that may or may not support combustion, in such a manner that the particles of the combustible gas are more or less dispersed in an isolated condition in the air or other gas, so that on ignition instead of an explosion ensuing, the flame will be communicated gradually from one combustible particle to another, thereby effecting a gradual development of heat, and a corresponding gradual expansion of the gases, which will enable the motive power so produced to be utilized in the most effective manner. The mode of using the gases and the arrangement of the engine may be variously modified in carrying out this invention.

"Thus according to one arrangement the gases are introduced into the engine cylinder at atmospheric pressure. The cylinder is for this purpose provided with a slide having suitable ports for the admission of air and of an intimate mixture of combustible gas or vapour and air, and the movement of the slide is so regulated by means of a cam or eccentric on the engine shaft that during the first part of the stroke of the piston air alone enters the cylinder, while during a succeeding portion of the stroke the mixture of gas and air is introduced behind the air. This mixture in entering the cylinder will become more or less dispersed in the air previously introduced, the particles of the mixture being situated nearest together at the points where they enter the cylinder, and becoming gradually more dispersed as they mix with the air in front. A communication being now established by the slide between a small external gas-flame and the contents of the cylinder at the point where the combustible mixture is most dense, this ignites and the combustion of the whole charge takes place gradually, the mixture burning with gradually decreasing rapidity as the flame extends to those particles that are more diffused among the air. The gradual expansion of the gases thus produced causes the piston to complete its stroke,

1 Only so much is given as is required to understand the points at issue. This abstract is made with the aid of original documents kindly furnished by Messrs Faithfull & Owen.