That it was not anticipated.

That there was a sufficient improvement on the then state of public knowledge to render the patent valid.

Per Lord Herschell, L.C. (at p. 360): "It is quite true that the change" (i.e. difference between the Aberdeen machine and Lyon's) “is but small; but if it be the case that the change was made with a view to the use of steam at a comparatively high pressure in the inner cylinder, and consequently rapid disinfection, and that the plaintiff” (Lyon) "for the first time put before the public a machine adapted for that purpose, although the difference between that machine and any machine in prior use might be slight, it appears to me to be none the less the subject-matter of a patent.

"But the matter which, I confess, has given me the greatest difficulty, and which has led me to entertain some doubt whether the judgment can be sustained, is that which I have indicated, namely, whether the plaintiff does, on the face of his specification, indicate the intention that the steam in the inner chamber is to be used at a considerable pressure, and that the apparatus has been devised accordingly. I confess that I think this case very near the line. I think it is unfortunate that the plaintiff was not more specific in his description on the face of his specification; because if he had been so, very possibly he might not have been subject to the difficulties which he has had to encounter in this litigation. . . .

As to construction: "When one turns to the drawing to which those letters and figures have reference, one finds a door firmly fastened by a great number of nuts and bolts at short intervals all round the door. Now it seems to me that any one reading that specification in connection with the drawing could come to no other conclusion than this, that inside that inner chamber there was to be used steam at a considerable pressure, because safeguards are introduced to render the door capable of withstanding a considerable pressure; and it can hardly be supposed that this large number of nuts and bolts were introduced out of mere wantonness."

Lord Watson (at p. 363): "The only essential difference between the two apparatus appears to me to consist in this: That in the respondent's" (Lyon's) "the purifying chamber is fitted with a door capable of resisting, and therefore enabling the process of purification to be carried on with highpressure steam. If the Aberdeen apparatus had been made with a door to the inner chamber, which would have permitted the use of high-pressure steam within it, the respondent's invention would, in my opinion, have been thereby anticipated."

1895. LEONHARDT & Co. v. KALLÉ & Co., 12 R. P. C. 103.

Inventive Ingenuity-Sufficiency of Directions.

In 1888 a patent (No. 2664) was granted to H. H. Lake for an invention (communicated from abroad) for "improvements relating to the production of colouring-matters."

The complete specification was as follows:

"It has been found that from para-nitro-toluol-sulpho-acid a number of yellow, orange to brown colouring matters can be produced which have the property of dyeing cotton direct and fast to alkali without mordant.

"The formation of these colouring matters is effected in such a manner that oxidable organic or mineralic substances and free caustic alkali in a dissolving or distributing agent act under heat, upon paranitrotoluolsulpho acid or its salts.

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As such oxidable substances I mention for example: methyl alcohol; ethyl alcohol; glycerine; resorcine ; xantongenate of potassium, &c. ; hydroquinone; orcin; naphthol; dioxynaphthaline; pyrogalic acid; resorcylic acid; oxynaphthoic acid; gallic acid; tannic acid and substances containing tannic acid, for example sumach, catechu, and the like; oxyquinoline carbonic acid; dioxynaphthalinesulpho-acid; sulphurous acid; arsenious acid; antimonious acid or its salts.

"The above-mentioned substances have given good results, but other oxidable substances can be used in lieu thereof, for which reason I do not limit myself to those above enumerated.

"The process which I use for the preparation of these new colouringmatters is in general as follows: I dissolve or distribute paranitrotoluolsulphoacid or a salt of this acid, under addition of such oxidable substances, in water, or one of the above-mentioned liquid oxidable agents, for example spirit, glycerine, and heat the same with caustic alkali until the formation of colouring-matter has terminated.

"By employing more or less of the oxidable substances the shades of the colouring-matters obtained can be greatly varied.

"In order to render the process better understood I give the following examples, to which however I do not limit myself, as they can be variously modified without departing from the nature of the invention.

"Example 1.-Upon 10 kilogrammes of the sodium salt of paranitrotoluolsulpho-acid, or an equivalent quantity of the free acid, are poured about 30 litres of spirit or methyl alcohol and heated in a vessel provided with an agitator and a reflux-cooler. About 8 kilogrammes of caustic soda-lye of 40 degrees Baumé are then gradually added, and the whole is heated to ebullition. The colouring-matter obtained is filtered, pressed, and

dried.

"Example 2.-10 kilogrammes of paranitrotoluolsulpho-acid are heated together with about 20 kilogrammes of glycerine, and to the mixture is gradually added, at about 60 degrees centigrade, about 8 kilogrammes of caustic soda-lye of 40 degrees Baumé. A powerful reaction which may occur, and which is accompanied by strong ebullition, is met by adding cold water or by externally cooling the vessel. The formation of colouringmatter is terminated in a short time. The thick paste obtained is gradually introduced into about 100 litres of boiling salt water which must be kept acid up to the end, preferably by means of acetic acid. The colouringmatter thus separated is filtered, pressed, and dried.

"Example 3.20 kilogrammes of sodium salt of paranitrotoluolsulphoacid and 4 kilogrammes of resorcine are dissolved in 60 litres of hot water, 20 kilogrammes of caustic soda-lye of 40 degrees Baumé are added, and the mass is boiled up to the end of the formation of the colouring-matter. The colouring-matter is precipitated by neutralization with an acid, and by the addition of common salt in the usual manner.

"Example 4-5 kilogrammes of a naphthol are dissolved in 20 kilogrammes of caustic soda-lye of 40 degrees Baumé and 60 litres of water, 20 kilogrammes of the sodium salt of paranitrotoluolsulpho-acid are added, heat being applied until the formation of colouring-matter is terminated. The colouring-matter is then separated in the usual manner.

"The same process serves for the production of colouring-matters by means of naphthol dioxynaphthalines and its sulpho acids: pyrogallic acid; resorcylic acid; oxynaphthoic acids; gallic acid; tannic acid and substances containing tannic acid, such as sumach, mirabolane, catechu, and the like; oxyquinoline carbonic acid.

"Example 5.-10 kilogrammes of sodium sulphite are dissolved in 60 litres of water and 20 kilogrammes of caustic soda-lye, then 20 kilogrammes of the sodium salt of paranitrotoluolsulpho-acid added, and the whole boiled.

"Example 6.-6.5 kilogrammes of arsenious acid are dissolved in 150 litres of and 20 kilogrammes of caustic soda-lye, then 20 kilogrammes of the sodium salt of paranitrotoluolsulpho-acid added, the whole being heated as long as colouring-matter is formed.

"In the above directions I always speak of caustic alkali in the form of lye (aqueous solution), but it is a matter of course that in certain cases the alkali can be used in another form. In some cases, in lieu of caustic soda or caustic potash, caustic baryta or caustic strontia can be used. Furthermore, the operation can be carried out in a closed vessel with or without suitable pressure."

The claim was for :

"The process of producing colouring-matters fast to alkali which will dye cotton yellow, orange to brown without mordant, by the action of suitable oxidable substances, and fix' alkalies upon paranitrotoluolsulphoacid under heat, substantially as described."

In the action for infringement the chief defences raised were :—

(1) Insufficiency of the specification in not showing how to distinguish the suitable oxidable substances, in not giving proportions, in not defining how different shades of colour could be produced, and in not giving the chemical composition of the dye produced.

(2) That the claim was too wide, and would include substances such as zine dust that would not do.

(3) That it was not a new invention, being anticipated in several publications, and amongst others Lake's specification, No. 4387* of 1886.

This word "fix" should be free or fixed, more probably the latter, but it is immaterial which is correct.

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This alleged anticipation of 1886 was a new mode of producing certain dyes. The process consisted in the first place of boiling paranitrotoluolThe result was sulphonic acid with caustic soda. an intensely red fluid, from which a yellow colouring-matter' may be obtained by salting out," but the salting out was not done, and there was added " to the fluid as much zinc-dust as necessary to render the fluid colourless." The zinc-dust was a powerful reducing agent. The new amidosulpho acid was then purified and used with other organic substances to produce a series of dyes. The inventor subsequently discovered that by adopting a slower process of deoxidation (e.g. by using less active agents), and by stopping the process. when colouring-matter ceased to be formed he got a new dye which was fast to alkali and could be used on cotton without a mordant. In the former and more rapid process these colouring-matters were supposed to have been made and destroyed. The specification sued on and above set out is that for this new process of slower oxidation.

Held, that the discovery of the mode of stopping of the older process at a given stage by slower oxidation was a patentable invention, that the directions were sufficient, and that the claim was not too wide.

Mr. Justice Romer first dealt with the alleged anticipations, and found the process was novel and was good subject-matter for a patent.

As to other objections (at p. 116): “Objection I contends that the complete specification is ambiguous and misleading on certain grounds. In my opinion it is not ambiguous and not misleading. Let me deal with the various heads on which that contention is based in objection 1. Take objection (), which is that the specification 'shows no means for ascertaining what oxidisable substances are not suitable.' Now with reference to that, what has the patentee done, and what really could he do more? He has pointed out numerous oxidisable substances, and admittedly those oxidisable substances he mentioned are as good, if not better, and more easily dealt

1 The soda salt here mentioned is known commercially as "sun yellow" (C14H,N2S¿Na ̧O;), and its constitution is represented by the formula

The formula for the new dyes ("Mikado" colours) has not been finally determined, but is, according to Hurst, similar to the above, with the condensation atom of O replaced by (CH3)2, N- N

N-N

with, than the other oxidisable substances which are not specifically mentioned. . . . I do not think that he was bound to specify all possible oxidisable substances that could be used, or to point out which of the oxidisable substances not mentioned should rather be avoided as not being so good as those expressly mentioned."

As to the giving of proportions (at p. 117): "He has taken numerous examples and given details with regard to numerous oxidisable substances, how they are to be used, in what proportions, and with every necessary information. . . . He was not bound to apply a theory. He was bound to give the best result. If he had formed a theory the objection would have been taken against the theory. He has done what in my opinion is right. He has shown how to obtain the best result from the different oxidisable substances in fact, and not in theory."

As to the shades produced (at p. 118): "It is very difficult to define colours. . . . The patentee has pointed out what colours his dye produce. Undoubtedly all the colours that are produced from his process are rightly stated by the limits given in the specification. Practically there would be no difficulty. A person wanting to use these dyes would test the examples given." The learned judge alluded to the objection as to the absence of any formula for the product as being "another example of an unfair objection. In my opinion the patentee was not bound to state anything of the kind."

1895. NOBEL'S EXPLOSIVES Co., LTD. v. ANDERSON, 12 R. P. C. 164.

Construction of Specification.

A patent (No. 1471 of 1888) was granted to A. V. Newton for an invention (A. Nobel's) for "improvements in the manufacture of explosives." The complete specification began by describing the object of the invention :

"The object of this invention is to combine the substances nitroglycerine and nitrated cellulose, with or without nitro-starch or nitrodextrine, or both, so as to produce an explosive substance of a horny or semi-horny character, and capable of being reduced to grains suitable for use as a propeller of projectiles." Various processes of manufacture were described. The proportions were indicated. "The limit of variation, as regards the relative proportions of the two ingredients above named, viz. nitro-glycerine and soluble nitrated cellulose, which permits of obtaining a compound consistent enough to be granulated, is very wide. But when the proportion of nitro-glycerine exceeds two-thirds of the compound, it is rather too soft, and when, on the contrary, nitrated cellulose is in excess of two-thirds, it becomes too tough and hard to be easily granulated." Throughout the specification "insoluble" nitro-cellulose was never mentioned, but frequently the terms "soluble nitrated cellulose" and nitrocellulose of the "well-known soluble kind" were used.