Mr. Siemens, in his address before the Mechanical Science Section of the British Association, took occasion to make some remarks on the patent laws of England, of which the following is an extract: ” Closely allied to the question of education is that of the system of letters patent. A patent. is, according to modern views, a contract between the commonwealth and an individual who has discovered a method, peculiar 1o himself, of accomplishing a result of general utility. The State, being interested to secure the information and to induce the inventor to put his invention into practice, grants him the exclusive right of practicing it, or of authorizing others to do so, for a for a limited- number of years, in consideration or his making a full and sufficient description of the same. Unfortunately, this simple and equitable theory of the patent system is very imperfectly carried out,and is beset with various objectionable practices, which render a patent sometimes an impediment to, rather than a furtherance of applied science, and sometimes involve the author of an invention in endless legal contentions and disaster, instead of procuring for him the intended reward. These evils are so great and palpable, that many persons, including men of undoubted sincerity and sound judgment on most subjects, advocate the entire abolition of t%» patent laws. They argue that the desire to publish the relults of our mental labor suffices to insure to the commonwealth the possession of all new discoveries or inventions,and that justice might be done to meritorious inventors by giving them national rewards. ” This argument may hold good as regards a scientific discovery, where the labor bestowed is purely mental, and carries with it the pleasurable excitement peculiar to the exercise and advancement of science on the part of the devotee ; but a practical invention has to be regarded as the result of a first conception, elaborated by experiments and their application to existing processes in the face of practical difficulties, of prejudice, and of various discouragements, involving also great expenditure of time and money, which no man can well afford to give away, nor can men of merit be expected to advocate their cause before the national tribunal of rewards, where, at present, only very narrow and imperfect views of the ultimate importance of a new invention woulrl. be taken, not to speak of the favoritism to which the doors would be thrown open. Practical men would undoubtedly prefer either to exercise their inventions in secret, where that is possible, or to desist from following up their ideas to the point of their practical realization. If we review the progress of the technical arts of our time, we may trace important practical inventions almost without exception to the patent office. In cases where the inventor of a machine or process happened to belong to a nation without an efficient patent law, we find that he readily transferred the scene of his activity to the country offering him the greatest encouragement, there to swell the ranks of intelligent workers. Whether we look upon the powerful appliances that fashion shapeless masses of iron and steel into railway wheels or axles,or into the more delicate parts of machinery; whether we look upon the complex machinery in our cotton factories, our dye works, and paper mills, or into a Birmingham manufactory, where steel pens, buttons, pens, buckles, screws, pencil cases, and other objects of general utility are produced by carefully elaborated machinery at an extremely low cost ; or whether we look upon our agricultural machinery by which England is enabled to compete, without protection, against the Russian or Dan-ubian agriculturist, with cheap labor and cheap land to back him, in nearly all cases we find that the machinery has been designed and elaborated in its details by a patentee who did not rest satisfied till he had persuaded the manufacturers to adopt the same, and removed all their real or imaginary obj ections to the innovation. We also find that the know ledge of its construction reaches the public directly or indirectly through the patent office, thus enlarging the basis for further inventive progress. ” The greatest illustration of the beneficial working of the patent laws was supplied,in my opinion, by James Watt,when just about 100 years ago, he patented his invention of a hot working cylinder and separate steam engine condenser. After years of contest against those adverse circumstances that beset every important innovation, James Watt, with failing health and scanty means was only upheld in his struggle by the deep conviction of the ultimate triumph of his cause. This conviction gave him confidence to enlist the cooperation of a second capitalist, after the first had failed him, and of asking for an extension of his declining patent. ” Without this opportune help Watt could not have'succeed-ed in maturing his invention ; he would, in all probability, have relapsed into the mere instrument-maker, with broken health and broken heart, and the invention of the steam engine would not only have been retarded for a generation or two, but its final progress would have been based probably upon the coarser conceptions of Papin, Savory, and New-comen. ” It can easily be shown that the perfect conception of the physical nature of steam which dwelt like a heaven-born inspiration in Watt's mind was neither understood by his co-temporaries nor by his followers up to very recent times, nor it be gathered from Watt's very imperfect specification. James Watt was not satisfied to exclude the condensing water from his working cylinder, and to surround the same by by non-conducting substances, but he placed between the cylinder and the non-conducting envelope a source of heat in the form of a steam jacket, filled with steam at a pressure somewhat superior to that of the working steam. His successors have not onlydiscarded the steam jacket,and even condemned it, on the superficial plea that the jacket presented a larger and hotter surface for loss by radiation than the cylinder, but expansive working was actually rejected by some of them on the ground that no practical advantage could be obtained by it. The modern engine,notwithstanding our perfected means of construction, had in fact degenerated in many instances into a simple steam meter, constructed apparently with a view of emptying the boiler in the shortest possible space of time. "It is only during the last twenty years that the subtile action of saturated steam in condensing upon the sides of the cylinder when under pressure, and of evaporating when the pressure is relieved toward the end of each stroke, has been again recognized and insisted upon by Lechatelier and others who have shown the necessity of a slightly super-heated cylinder in order to realize the expansive force of steam. The result has been a reduction in the consumption of fuel in our best marine engines from six or eight to below three lbs. per gross, indicated horse-power. ” Would it be safe, in view of such facts as these, to discard the patent laws, which, as I have endeavored to show, lay at the very foundation of our modern progress, without making at all events a serious effort to remedy those evils, which, it admitted on all hands, now adhere to them ? These evils need, for the most part, no special legislation, but can be traced to the imperfect manner in which the existing patent laws are carried into effect. It is a hopeful circumstance that, during the next session of Parliament, the whole question of the patent laws is likely to be inquired into by a special committee, who, it is hoped, will act decidedly in the general interest without being influenced by special or professional claims. They will have it in their power to render the patent office an educational institution of the highest order."