Frazier, 43 Iowa, 177.—Documentary evidence. Evidence supplied by writings and documents of every kind in the widest sense of the term; evidence derived from conventional symbols (such as letters) by which ideas are represented on material substances.—Evidence aliunde. Evidence from outside, from another source. In certain cases a written instrument may be explained by evidence aliunde, that is, by evidence drawn from sources exterior to the instrument itself, e. g., the testimony of a witness to conversations, admissions, or preliminary negotiations.—Expert evidence. Testimony given in relation to some scientific, technical, or professional matter by experts, 4. e., persons qualified to speak authoritatively by reason of their special training, skill, or familiarity with the subject.—Extraneous evidence. With reference to a contract, deed, will, or any writing, extraneous evidence is such as is not furnished by the document itself, but is derived from outside sources; the same as evidence aliunde. (See supea.)—Hearsay evidence. Wvidence not proceeding from the persona] knowledge of the witness, but from the mere repetition of what he has heard others say. See, more fully, Hearsay.—Incompetent evidence. Evidence which is not adinissible under the established rules of evidence; evidence which the law does not permit to be presented at all, or in relation to the particular matter, on account of lack of originality or of some defect in the witness, the document, or the nature of the evidence itself. Texas Brewing Co. v. Dickey (Tex. Civ. App.) 43 S. W. 578; Bell v. Bumstead, 60 Hun, 580, 14 N. Y.