NEW. Something not known before.

2. To be patented, an invention must be new. When an invention has been described in a printed book which has been publicly circulated, and afterwards a person takes out a patent for it, his patent is invalid¹, because the invention was not new, 7 Mann' & Gr. 818. See New and Useful Invention.

NEW AND USEFUL INVENTION. This phrase is used in tlie act of congress relating to granting patents for inventions.

2. The invention to be patented must not only be new, but useful; that is, useful in contradistinction to frivolous² or mischievous³ inventions. It is not meant that the invention should in all cases be superior to the modes now in use for the same purposes. 1 Mason's C. C. R. 182; 1 Mason's C. C. R. 302; 4 Wash. C. C. R. 9: 1 Pet. C, C. R. 480, 481; 1 Paine's C. C. R. 203; 3 Mann. Gr. & Scott, 425. The law as to the usefulness of the invention is the same in France. Renouard, c. 5, s. 16, n. 1, page 177.

NEW FOR OLD. A term used in the law of insurance in cases of adjustment of a loss, when it has been but partial. In making such adjustment the rule is to apply the old materials towards the payment of the new, by deducting⁴ the value of them from the gross amount of the expenses for repairs, and to allow the deduction⁵ of one-third new for old upon the balance. See 1 Cowen, 265; 4 Cowen, 245; 4 Ohio, 284; 7 Pick. 259; 14 Pick. 141.

NEW or NOVEL ASSIGNMENT, pleading. Declarations are conceived in very general terms, and sometimes, from the nature of the action, are so framed as to be capable of covering several injuries. The effect of this is, that, in some cases, the defendant⁶ is not sufficiently⁷ guided by the declaration to the real cause of complaint; and is, therefore, led to apply his answer to a different matter from that which the plaintiff has in view. For example, it may happen that the plaintiff has, been twice assaulted by the defendant, and one of the assaults is justifiable⁸, being in self-defence, while the other may have been committed without legal excuse. Supposing the plaintiff to bring an action for the latter; from the generality of the statement in the declaration, the defendant is not informed to which of the two assaults the plaintiff means to refer. The defendant may, therefore, suppose, or affect to suppose, that the first is the assault intended, and will plead son assault demesne⁹. This plea the plaintiff cannot safely traverse, because an assault was in fact committed by the defendant, under the, circumstances of excuse here alleged¹⁰; the defendant would have a right under the issue joined upon such traverse, to prove these circumstances, and to presume that such assault, and no other, was the cause of action. The plaintiff, therefore, in the supposed case, not being able safely to traverse, and having no ground either for demurrer, or for pleading in confession¹¹ and avoidance, has no course, but, by a new pleading, to correct the mistake occasioned by the generality of the declaration, and to declare that he brought his action not for the first but for the second assault and this is called a new assignment. Steph. PI. 241-243.

2. As the object of a new assignment is to correct a mistake occasioned by the generality of the declaration, it always occurs in answer to a plea, and is therefore in the nature of a replication. It is not used in any other part of the pleading.

3. Several new assignments may occur in the course of the same series of pleading.

4. Thus in the above example, if it be supposed that three distinct assaults had been committed, two of which were justifiable, the defendant might plead as above to the declaration, and 'then, by way of plea to the new assignment,, he might again justify¹², in the same manner, another assault; upon which it would be necessary for the plaintiff to new-assign a third; and this upon the first principle by which the first new assignment was required. 1 Chit. PI. 614; 1 Saund. 299 c.

5. A new assignment is said to be in the nature of a new declaration. Bac. Abr. Trespass¹³ I, 4, 2; 1 Saund. 299 c. It seems, however, more properly considered as a repetition of the declaration; 1 Chit. PI. 602; differing only in this, that it distinguishes the true ground of complaint, as being different from that which is covered by the plea. Being in the nature of a new or repeated declaration, it is consequently to be framed with as much certainty or specification¹⁴ of circumstances, as the declaration itself. In some cases, indeed, it should be even more particular. Bac. Abr. Trespass, I 4, 2; 1 Chitt. Pl. 610; Steph. Pl. 245. See 3 Bl. Com. 311; Arch. Civ. 318; Lawes' Civ. PI. Pl. 286; Doct. Pl. 318; Lawes' Civ. Pl. 163.