The law of Patents is but a little more than two centuries old, in England; and on the continent of Europe it began still later. In this country a statute authorizing and regulating patents was enacted in 1790, and upon this and subsequent amendatory statutes the law of patents rests. In itself it is utterly unknown to the common law; but the rules and principles of the common law, as to contract, construction, evidence and remedy, are applied to the law of patents. The last statute, which covers the whole ground and replaces the earliest enactments, was approved July 8, 1870. (a)

We propose to consider the law of patents only in its relation to the law of contracts. We would say, however, that as to the methods and processes of obtaining patents, any applicant at the patent-office in Washington is furnished not only with a copy of the statute, but with a carefully-prepared pamphlet, in which full directions are given for the transaction of any business with the office. And the experience of the author of this work justifies his saying that any person having or wishing to have dealings with the patent-office, as counsel or otherwise, may be sure of receiving from the officers employed therein all the guidance and assistance compatible with the discharge of their duties.

(a) The English legislation upon this subject rests upon a clause in the Statute 21 Jac. 1, c. 3, § 6, commonly called the Statute of Monopolies, exempting from the operation of that act "letters-patent and grants of privilege, for the term of fourteen years or under, of the sole working or making of any manner of new manufactures within this realm, to the true and first inventor and inventors of such manufactures, which others, at the time of making such letters-patent and grants, shall not use, so as also they be not contrary to law, nor mischievous to the state by raising prices of commodities at home, or hurt of trade, or generally inconvenient."