this is the result. In the year 1823 this substance was called coal-oil, volatile-oil, and spirits of tar; it had various names; it was known as coal-oil then, but of late years more as naptha.

Cross-examined by Mr. Serjeant Talfourd.

A much greater proportion of this coal-oil can be obtained in gas-works according to the circumstances under which they conduct the process called condensing, or cooling, or refrigerating the gasses. If you let the whole of the products of condensing go together with that which is condensed in a high temperature, and that which is condensed on a much lower temperature, you will see but little of this coal-oil, and it will be a general mass of coal-tar: to separate these, it must undergo the process of distillation; but from the mode of cooling the gas, which is often rather differently done, then you may separate them in a much higher ratio.

Re-examined by the Attorney-General. Independently of any peculiar means used for condensation, there has always been a considerable product of the coal-oil in the gas-works since I have known them; independently of the coal-oil which may be in combination with the tar. We use Newcastle coal. I think we could supply from our works alone of this coal-oil which is separated in the first instance, independent of that which is in combination with the tar, 7 or 800 gallons weekly. I think there are eight or nine other establishments in London. I should say the supply altogether, speaking within moderate bounds, would be from all at least 3,000 gallons a week of the coal-oil, from the first distillation of the coal.

Alexander Garden, examined by the AttorneyGeneral.

I am a practical chemist, carrying on business in Oxford-street. I have read the specification of Macintosh's patent, and think there can be no difficulty in making the fabric from the directions there given. I never heard of a similar process before that patent. I have myself made some experiments in accordance to the specification described by Mr. Macintosh in his patent, and applied the solved caoutchouc to some fabrics, which made them impervious to water. I employed two kinds of coal-oil-one I obtained from Mr. Cassell's, and the other, I think, was sent to me by Mr. Blunt. I know what coal-oil is perfectly well; I have known it many years, ever since the introduction of gas; it is obtained in the distillation of coal, and commonly called coal-oil, and known by that name. These specimens are water-proof, and

cemented together by means of the dissolved caoutchouc. I have got some specimens of the cement here, which I made myself from the coal-oil and the India-rubber, about the consistence of honey; I put it on with a common painting-brush. I have made some experiments upon what is called Clarke's process; I prepared some agreeably to it, but I have not been successful. I pursued exactly the directions given; tried as sincerely to follow that as I did Mr. Macintosh's; I had no intention to do otherwise, I did my best to ascertain the result. The linseed-oil and caoutchouc form a compound something like bird-lime. With regard to Macintosh's, when the coal-oil is evaporated the Indiarubber remains in its original form, and with its original properties. I have not tried what is called Weisse's process; it appeared to me there was no chance of succeeding in it, therefore I did not attempt it. From the description of Weisse's, it is not at all like Macintosh's, totally different. I received from Mr. White, who has been examined here, a piece of the cloak which he bought at Messrs.Everington and Ellis's, and analysed it. It is not made according to Clarke's process, nor according to Weisse's, but I should say according to Macintosh's; I have no doubt about it. I obtained elastic gum from it with quite the same properties as that which Macintosh does by digesting caoutchouc in coal-oil. I put the cloth into a bottle with some coal-oil, and digested it in that for some time; and I found that I obtained a solution of Indiarubber, which I procured by evaporating the coal-oil, and I got India-rubber as the residuum. I know the coal-oil in what is called its crude form, as it is found after the distillation of the coal. I saw it, as I mentioned, at the time gas-light was first introduced; I received the products from Mr. Winsor, who was the introducer of gas. I have made experiments with coal-oil in its original form in dissolving India-rubber, and it answered equally well.

Cross-examined by Mr. Rotch.

The specification directs that the substances that are to be united be stretched on frames before put together. I found nothing in my analysis of the piece of cloak that told me any thing about the frames; that was impossible for me to tell. I could only tell by my analysis that it had India-rubber in its composition; and finding it interposed between the two pieces of cloth, it appeared to me to resemble that of Mr. Macintosh. The solution with crude oil, when I had mixed the India-rubber with it, I put through a fine wire-sieve, in the same manner as the other; and the mixture was entirely free from any granulated particles, and perfectly

smooth, scarcely any thing remained. I put that solution also on with a brush in the same manner exactly; it was cold when I put it on. I think that it might be divested of a great deal of its smell; if it was exposed to heat it would dry, and the smell would go off. I do not know that the crude oil has been considered unfit for use without being rectified; on the contrary, it answers the purpose of dissolving, and renders the cloth waterproof, but when rectified it will be, no doubt, infinitely better. When I saw his patent, I should not have known whether it was crude oil or rectified oil that was to be used, only he speaks of various degrees of purity, therefore I should presume the oil was made as pure as possible, If he had particularly specified crude oil, I should naturally have used crude oil.

Re-examined by the Attorney-General.

The cloth manufactured from what is called the oil in its crude state is quite impervious to water, and I should expect therefore that it would be impervious to air. I think it might be cleared or freed from that smell; but with that smell it might be usefully employed in covering carts and for other purposes. If it were put in a room heated from 100 to 140 degrees, I think that probably would rid it of the disagreeable effluvia, or a great deal of it. This substance, before it has been re-distilled, and after it has been redistilled, is still called coal-oil.

Dr. Turner examined.

I am a Professor of Chemistry at the London University, and Fellow of the Royal Society; I am acquainted with Mr. Macintosh's patent and the specification; I knew of the invention at the time it was first made public in 1823; I was residing in Edinburgh when I heard of it; in my opinion it was at that time new. I have not minutely attended to manufacturing chemistry, but I scarcely think it could have been a discovery of any importance without my knowing it. I am acquainted with the manufacture of coal-gas in a general way, and I have visited many gas manufactories; I have known coal-oil for a number of years; I have known the nature of the substance ever since I have known the nature of coal-gas; I became familiar to some extent with such subjects about 1823. I should conceive those persons well acquainted with the subject, must be acquainted with the substance called coal-oil. The mineral naptha and coal-oil I conceive chemically to be different substances; the mineral naptha is a substance which properly has the term naptha applied to it. I have gone through the processes of Mr. Macintosh, not minutely, but in a general way,

and the specification appears to me to pro perly describe the process.

Mr. Arthur Aiken, examined by Mr. Serjeant Bompas.

I am the Secretary of the Society of Arts; I remember the time when Macintosh's patent first came out. About the time, as far as can recollect, the patent was taken out, had the pleasure of seeing Mr. Macintosh at a Chemical Club, which met in London, and he was introduced to that club, I think, as far as I recollect, by Dr. Wollaston; and at that time specimens were handed to us as being a new article; according to my judgment it was at that time a new invention; I never heard of any thing similar to it before; I know the substance called coal-oil; it is one of the products in the manufacture of coal-gas, if it is wished to be made pure, the common mode of purifying a substance of that kind would be by distillation. I have devoted some attention to India-rubber, and have occasionally made experiments upon it. The temperature of boiling oil is so near that in which India-rubber itself undergoes decomposition, that I should expect if Indiarubber were put into it, it would be blackened and more or less decomposed.

Mr. James Bowman Neilson, examined by Mr. Watson.

I have been Manager of the Glasgow Gasworks eighteen or nineteen years; we burn entirely Cannel coal; in making the gas we have deposits of tar, ammoniacal-water, and coal-oil; all these substances are separate and distinct; I find the coal-oil in what I call the tar-pit, also in the condenser, and in the mains in the street; I find it also on the surface of the ammoniacal liquor. The first person that obtained it from the Glasgow works was Mr. Macintosh, about the year 1819 or 1820; he continued taking it till about six years ago; before that time a Mr. Thompson took the tar of us for the purpose of making mineral paints. Before Mr. Macintosh got it, we were obliged to dispose of it as we best could; to treat it as refuse; it was carted out into the country some miles, and put upon the land. Since Mr. Macintosh has discontinued taking the coal-tar, we have used it for fuel; Mr. Macintosh has taken the ammoniacal-water and the coal-oil since-all that was produced a very considerable quantity. The quantity of the ammoniacal-water we get in the course of a year would be about 230,000 gallons, and of oil, I believe I should say, upwards of 6,000 gallons. I have tried it in the crude state, before distillation, as to its effect on Indiarubber; I merely did so for the purpose of satisfying myself, that the coal-oil in a crude state before distillation would dissolve India

rubber. I have seen Mr. Macintosh's specification.

Cross-examined by Mr. Serjeant Wilde.

I am the Manager of the Gas-works. The products were pumped off from the receptacle where they were collected, and I always found the tar was pumped first, the ammoniacal liquid was next, and the coal-oil was pumped last these oils were put into one vessel just as they were pumped. Since the alteration he has taken the product of the coal, with the exception of the tar, in the same way. I form my judgment as to the quantity of coaloil, as compared with the quantity of ammo. niacal liquor, by the eye. I have sent hundreds of gallons from one of our gas-holders; I measure the quantity of gas that I give out per twenty-four hours; the average quantity throughout the year, I make about 25,000 cubic feet in an hour in the winter, and about 10,000 to 12,000 in the summer, that is at one set of works; I never separated any of the coal-oil, it separates itself; I only sent it once in a separate vessel; it was of a yellowish colour-a yellow brown.

Re-examined by Mr. Attorney-General.

The oil and the ammoniacal liquid were entirely separate products; they separate themselves so that they might have been kept apart without difficulty; the oil could have been taken from the surface of the ammoniacal liquor, and put into a separate vessel if that had been wished to have been done. We can draw away the liquor and allow the oil to remain, and we can draw away the tar and allow the ammoniacal liquor to remain. First the tar, then the ammoniacal liquor, and then the oil, all right well. This sub. stance which floats on the top of the ammoniacal liquor goes by the name of coal-oil. Mr. Ewart, examined by Mr. Attorney

General.

I am now chief Engineer and Inspector of Machinery to the Admiralty. I have had occasion to see how Mr. Macintosh's manufactory was conducted in making of waterproof cloth; it began in 1823; I directed the construction of the machinery; I was about to be engaged or concerned in trade with Mr. Macintosh at that time; I know the specification, and the manufacture was carried on according to that specification in Manchester. It was laid on by a brush; the brushes were worked by machinery instead of by hand; I continued to see how it was done till 1826; I have seen the cloth so manufactured tested, and tested it myself very often, and it was water-proof and air-proof; it was equally air and water-proof before the machinery was applied; I was there when the brush was worked by the hand; there was no

difference in the production, whether worked by the hand, or worked by power.

Cross-examined by Mr. Serjeant Wilde.

I am speaking of that branch of the manufacture which relates to laying of the solution on the cloth; the solution came from Glasgow ready prepared; I was there at the time of discontinuing the brush with the hand, and using the brush attached to the machinery; when the brush was applied by machinery, there was a trough attached to the machine.

George Palmer, examined by the AttorneyGeneral.

I am the Manager of the Metropolitan Gas-Works. We use Cannel coal, which produces an article called coal-oil. This oil has always combined with it a certain portion of tar. The proportion of coal-oil that can be separately drawn off is about 2 gal. lons to each 10,000 cubic feet of gas. It can be drawn off without difficulty, being specifically lighter than the tar and liquor, &c., and floats on the surface. This specimen has not been re-distilled. Sometimes the oil taken immediately from the gas-main is nearly as good as that re-distilled. We have not been in the habit of selling the coal-oil in a separate state, it is sold with the tar; but the price is increased which is given for the tar in proportion to the quantity of materials it contains. The first experiments made to ascertain the quantity of this coal-oil was, to my knowledge, in 1829, when the public were made fully acquainted with it by a work which was published by Mr. Attwood. The specimens of coal-oil produced are obtained in the common manufacture of gas.

Dr. Fitton, examined by the AttorneyGeneral.

I am a physician, and have attended to philosophical and scientific pursuits. I am acquainted with Mr. Macintosh's patent. I have not attended to chemistry for many years, but I have been a member of the Chemical Club, where this subject was mentioned, I think, about the latter end of 1823 and 1824. Dr. Wollaston was a member of that club. I had there an opportunity of hearing a great deal about Mr. Macintosh's patent. From what I heard then and since, I believe it to be new.

Mr. Children, examined by the AttorneyGeneral.

I am Secretary of the Royal Society. I am acquainted with Mr. Macintosh's process for making cloth water-proof and air-tight. As far as my knowledge goes, when it was introduced it was perfectly new.

Cross-examined by Mr. Serjeant Wilde. I have never heard of India-rubber being applied to any fabric to render it waterproof in the way applied by Mr. Macintosh.

The Attorney-General.―That is the plaintiff's case, my Lord.

Mr. Serjeant Wilde.-This is undoubtedly an important cause both to the plaintiff and the defendant, as well as to the public. My friend on the part of the plaintiff states, that Mr. Macintosh having been at the labour and pains of discovering an invention of great value, there ought to be preserved to him a remuneration adequate to that labour by an exclusive sale of the article; and I agree that in a case where an individual has by great labour, or even by accident, actually been the discoverer of some useful invention, by which the public are to be benefitted, he should be entitled, according to law, to the exclusive sale of the article patented; but, on the other side, and on behalf of the trade in general and of the public, I claim that an individual shall not, when the subject is generally before the public, step in and by an uncertain, vague description, lay his hand upon some useful manufacture, reserving to himself not something he has discovered, but something which he hopes either he or some other person will discover, and which when discovered shall refer back to his patent. My learned friend, on the part of this plaintiff, says, various persons had been engaged in trying to accomplish the object of procuring water-proof garments sufficiently light and flexible to be useful. The public were within a step of accomplishing this object; Mr. Macintosh, fortunately, advanced that step first. It is my case that he did not; that this is one of the many patents, which, when the attention of the public is flat, a man, by some means, gets, and seeks to maintain afterwards, by subsequent invention and discovery, he having little more knowledge, if any more, than the rest of the pub. lic at the time he gets it. It has been known for years before the patent, that India-rubber might be applied so as to render a fabric water-proof; and if this India-rubber is applied on the outside it will be inconvenient, have a clammy appearance, be disagreeable, and want renewing. If in the inside, it will be still more disagreeable, being next the person. "Oh, but," says Mr. Macintosh, "I will put a lining, and then I will get a patent." The solution that would render it water-proof is perfectly well known. In the specification he says, "I don't claim the solution, but I claim putting two fabrics together, and as they are wanted to stick, I shall press them." You don't want a patent for that; and this patent has no other object than putting two pieces of cloth together with a well-known solution of India-rubber be

tween.

To express it in the language of the Vice-Chancellor, he has got a patent for a sandwich he has put two things together, and got a patent for it. Now, I say, that the circumstance of his applying a known solution to a known purpose to produce a known result, clapping one piece of cloth over another-cannot be the subject of a legal patent. I shall read you the specification of a man of the name of Johnson, who got a patent years ago for using a solution of Indiarubber for cloth; he says, "take flock, such as you put on the paper of a room, and make a lining of that." This plaintiff says, "I will put a piece of cloth instead; and all these gentlemen from the club, by which our brains have been attempted to be knocked out, say, "We never heard of such a thing before," that is to say, they have not been attending to the matter. The defendants are not manufacturers, but deal largely in all articles of dress, and are glad to sell that for which there is the most demand. The only evidence of the infringement is, that certain parties have effected the same object as the patentee, and the witnesses know of no other means than those which the patentees use to effect that object. When Mr. Macintosh comes, on the ground of his having advanced only one step before the public, and claims to retain to himself the exclusive right to sell this article, he is bound to make out a perfect and a strict When the Crown grants the exclusive right, it is granted upon certain conditions ; and one express condition is, that the grantee shall, in consideration of the grant of the Crown for fourteen years, give the public the means of using that invention after the expiration of his patent in the best manner that he can inform them. There is a class of patents which ought to be narrowly watched-in which there is a vagueness and generality in the specification, partaking of that quality which my friend has ascribed to some of the specimens of bird-lime, catching all that comes within its grasp; and there is in this case an intended vagueness and generality, in order to cover any thing which might by Mr. M. or any body else be discovered thereafter. My learned friend says I claim for Mr. Macintosh the exclusive right of selling a coat formed of two pieces of cloth stuck together by an India-rubber cement; I say the patent was intended to claim more than that, not only fabrics stuck together by Indiarubber cement in a state of solution, but cloths stuck together by any flexible cement, not limited to India-rubber. Mr. Macintosh claims no right whatever in regard to the solution, except its application to the two pieces of fabric which are to be stuck together. He gives you in the specification the solution that is to be used; he tells you that is the best mode he has found out, and if

case.

that is untrue, he is not entitled to exclude the rest of the trade from participating with him. I will read you the specification, calling to your attention two points; first, whether it claims the putting two pieces of cloth together by means of any flexible cement, or by means of a flexible cement of India-rubber in a state of solution, only? And the second point is, what is the solution which Mr. Macintosh affects to tell you is the one that ought to be used to produce the desired effect? Mr. Macintosh says, "In compliance with the said proviso, I do hereby declare that my said invention doth consist in a manufacture of two or more pieces of linen, woollen, cotton, silk, leather, or paper, or other the like substances; any or either, or combination of any or either of the same, cemented together by means of a flexible cement." This passage amounts to this, I claim putting two pieces of cloth together by a cement-that is the substance of it-" the nature of which said manufacture is, that it is impervious to water and air." I should be glad to know what you find about India-rubber there. There is but one object in the paragraph which I have read, and that object is to state what his invention is, and in it there is not one statement about India-rubber. What possible cement could have been used that would not have fallen within it ?-None. Any flexible cement for the purpose of uniting two pieces of cloth together, and rendering them waterproof and air-proof, would be within this patent. He proceeds-"In further compliance with the patent, I hereby describe the process which I have found the best for performing the said manufacture." If I prove that Mr. Macintosh knew a better mode of performing his invention, that he used a better, that he never used the one described, then I shall prove an utter failure in the performance of his condition. In order to decide whether this was a bona fide disclosure, I questioned witnesses to ascertain how Mr. Macintosh did it, but was stopped. Mr. Macintosh has no new patent for any improvement; he manufactured this solution before 1823; he continues to manufacture it since 1823, and up to the present hour, and we are to discuss whether he has disclosed the most useful mode of preparing it, which he was apprised of at the time, and for that purpose I was entitled to know how he now carried on the manufacture.

He says, "I prepare caoutchouc by cutting it into very thin shreds or parings, and then steep it in the substance which is produced in making coal-gas, commonly called coal-oil; the quality of these ingredients is extremely various." That is, the quality of the substance produced in making coal-oil; some part of it is found in main, that is a certain degree of purity; other parts are found in the condenser, that is of a certain

degree of purity and impurity; other parts are found pure, and therefore all varying in purity, according, apparently, to the degree of distance to which its volatility has tended to carry it," and the relative proportions to be employed must depend on the quality of each; but when the caoutchouc is of the best quality, and the oil pure, from ten to twelve ounces of the former to a wine-gallon of the latter will be found to answer." Now this is the best mode that Mr. Macintosh has found of dissolving the caoutchouc or India-rubber. "This infusion I submit to a gentle heat obtained from a water or steam-bath, and I employ constant trituration until such time as the ingredients are reduced to a thin pulpy mass; when to render the whole as homogeneous as possible, I pass it through a very fine wire or silk sieve or searce, and if this part of the process has been duly followed out, the varnish will then be without any granular particles, and will, in appearance, resemble thin transparent honey; fabrics or substances effectually united by cement thus prepared in whatever way the union is effected, become both air and water-proof; but with a view to prevent the cement from appearing upon the surface of the manufactured articles, and to insure, at the same time, a perfect union of the substances, I, in the first place, distend the substances to be united, and with a brush or other suitable instrument, lay upon the surface of each an uniform layer or coating of the varnish or cement; and when this coating has, from evaporation of the oil, which is extremely volatile, acquired a clammy viscous consistency, and this will take place in a shorter or a longer space, in proportion to the heat of the atmosphere, and the current of air in which the manufacture is carried on, or to which the coated surfaces may be exposed, I apply the varnished side of both substances to each other, and, by means of a calender or rollers, or other suitable means, I powerfully press the fabrics or substances together, whereby they become united, and are rendered a compound fabric or substance; and thereafter I expose this compound fabric or substance in a stoveroom, or other suitable place, to a heat of from 100 to 140 degrees, for the double purpose of maturing the manufacture and obtaining a further evaporation of the oil, which, while it remains, gives off a disagreeable effluvium. When the substances to be united are of an open texture, or not of a smooth uniform surface, apply a greater number of coatings of the cement or varnish, and when three or more fabrics or substances are to be united together, I coat with the varnish the substance or substances to be enclosed on both sides, and complete the process as before suggested; farther it may, in some cases, be sufficient to apply the layer or