"_Provided, nevertheless_, That the above specifications shall not be held to limit the subject-matter of copyright as defined in section four of this Act, nor shall any error in classification invalidate or impair the copyright protection secured under this Act." {Sidenote: Prints and labels excluded} Prints or labels "not connected with the fine arts," but "designed to be used for any other articles of manufacture," are subject only to registration in the Patent Office in accordance with the act of June 18, 1874. {Sidenote: All the writings of an author} It is enacted (sec. 4): "That the works for which copyright may be secured under this Act shall include all the writings of an author," thus linking the phraseology of the law with the provision in the Constitution of the United States in which the word "writings" is used, with the effect of construing that word by the classification above cited. {Sidenote: Component parts} It is also enacted (sec. 3): "That the copyright provided by this Act shall protect all the copyrightable component parts of the work copyrighted, and all matter therein in which copyright is already subsisting, but without extending the duration or scope of such copyright. The copyright upon composite works or periodicals shall give to the proprietor thereof all the rights in respect thereto which he would have if each part were individually copyrighted under this Act." {Sidenote: Compilations, new editions, etc.} It is also enacted (sec. 6): "That compilations or abridgments, adaptations, arrangements, dramatizations, translations, or other versions of works in the public domain, or of copyrighted works when produced with the consent of the proprietor of the copyright in such works, or works republished with new matter, shall be regarded as new works subject to copyright under the provisions of this Act; but the publication of any such new works shall not affect the force or validity of any subsisting copyright upon the matter employed or any part thereof, or be construed to imply an exclusive right to such use of the original works, or to secure or extend copyright in such original works." {Sidenote: Non-copyrightable works} The provisions of the law regarding the subject-matter of copyright are completed by the negative provision: