That a hypothetical question does not embrace all the facts in the record does not render it erroneous, or that it includes the personal knowledge of the expert witness does not render it fatally defective, where the extent of that knowledge is so proved as to disclose the actual basis of his opinion.18 A mere statement to an expert witness introductory to a hypothetical question, as to what the examiner intends to state in the question, adding nothing to the facts stated, does not render the question improper.19 It has been held that expert cannot be called upon to give an opinion upon facts in his mind and undisclosed, or on matters in part within his observation and in part derived from others.20 The form of hypothetical questions, and what may be embraced therein, should be left largely to the discretion of the trial court."1 The answer of an expert witness to a hypothetical question must be based on the hypothesis stated, and not on a consideration of what might or might not happen under certain conditions." 17 Chicago, R. I. & G. Ry. Co. v. Bentley, 143 P. 179, 43 Okl. 469. Where plaintiff, in an action for damages against a dentist for injuries re sulting from the use of unsterilized instruments in extracting a tooth, testifies that a hypodermic needle used was not sterilized, and there is evidence that the doctor himself said that the needle had not been sterilized, that it was new and used for the first time, and that the defendant had been seen to use such a needle without sterilizing it, hypothetical questions assuming that the defendant used instruments in a septic condition may be properly asked expert witnesses on part of plaintiff. Roark v. Greeno, 59 P. 655, 61 Kan. 299, reversing judgment in Greeno v. Roark, 56 P. 329, 8 Kan. App. 390. 18 Currey v. Robinson, 139 P. 1023, 92 Kan. 117. 19 Shawnee Gas & Electric Co. v. Hunt, 122 P. 673, 32 Okl. 368. 20 Western Union Tel. Co. v. Morris, 73 P. 108, 67 Kan, 410. Where it appeared that a witness had not heard all of the evidence on which he predicated his opinion as to the value of services of attorneys and that he probably erroneously assumed that their right to compensation under the contract of employment was contingent on success, it was error to permit him to state his opinion. Colley v. Sapp, 44 Okl. 16, 142 P. 989, judgment affirmed on rehearing 44 Okl. 16, 142 P. 1193. 21 Order of United Commercial Travelers of America v. Barnes, 90 P. 293, 75 Kan. 720. 22 City of Wichita v. Coggshall, 43 P. 842, 3 Kan. App. 540. The answer of an expert witness as to the distance to which sparks could be thrown from certain type of locomotive, is not incompetent because it must depend to a degree on atmospheric conditions and the inflammability of the combustible matter referred to, which considerations must have occurred to the jury in weighing the evidence. Saunders v. Atchison, T. & S. F. Ry. Co., 119 P. 552, 86 Kan. 56. Hypothetical questions, which call for information as to the time required to do certain work and the proper manner of doing same, are proper, where the evidence sought would aid the jury in finding the ultimate facts.23 An architect, who hears a description of work done by another architect in supervising a building with which the witness is acquainted, may state his opinion as to the value of such supervision.24 A farmer who is an expert on the value of a growing crop may state the facts from which his conclusion as to its value is derived to aid the jury in determining whether his estimate is correct.25 Where a witness is qualified as an expert as to weights of cattle, his testimony giving his judgment as to weights is admissible, though he stated he "guessed" they weighed a certain amount.26 Expert testimony of a physician may be based on hypothetical questions,27 on the facts proved in the case,28 of a physician on personal examination,29 or on his personal examination and knowledge of the injuries received by plaintiff.30 It is error to permit a physician to testify as an expert concerning 23 Healer v. Inkman, 146 P. 1172, 94 Kan. 594. 24 Mampe v. Kunkel, 148 P. 741, 95 Kan. 602. 25 Chicago, R. I. & P. Ry. Co. v. Johnson, 107 P. 662, 25 Okl. 76v, 27 L. R. A. (N. S.) 879. 26 Midland Valley R. Co. v. Adkins, 127 P. 867, 36 Okl. 15. 27 George v. Shannon, 142 P. 967, 92 Kan. 801, Ann. Cas. 1916B, 338. In an action by a railroad employé for personal injuries, it appeared that the injury was rupture and varicocele. A physician who had examined the injury, and who had heard plaintiff testify, testified, as an expert, that such injuries were generally the result of violence. On being asked whether, in his opinlon, the injury could have been caused in the manner stated by plaintiff, he replied that it must have been done by violence. Held, that the error was not prejudicial, since the testimony of plaintiff was very brief and clear. Atchison, T. & S. F. R. Co. v. Brassfield, 32 P. 814, 51 Kan. 167. In an action against the city for damages by an alleged fall on a dangerous sidewalk, where plaintiff testified as to the manner in which he fell, and that the fall caused a rupture in the region of the groin, it was not error to refuse to permit a physician who never examined plaintiff's injuries, but who had heard plaintiff's testimony, to give his opinion as to the probability of a person being injured as testified to by plaintiff. City of Ottawa v. Green, 83 P. 616, 72 Kan. 214. 28 George v. Shannon, 142 P. 967, 92 Kan. 801, Ann. Cas. 1916B, 338. HON.PL.& PRAC.-63 (993) the condition of a person examined by him, and to base his opinion partly on the history of the case as detailed to him by the patient or by some other person.31 A physician testifying as an expert may base his opinion on his observation and examination of the patient, and such opinion will not be inadmissible because based partly on the patient's statement as to his condition and feelings when received as necessary to an examination and proper treatment.32 Expert medical testimony, based on physical examination of the patient after his action for damages for personal injuries was begun, which apparently was made to enable the physician to testify, is not for that reason alone incompetent, though it may materially affect its credibility.33 Medical experts, in response to hypothetical questions, are not required to answer with certainty, but may give their opinions as to the cause of certain physical conditions.34 Where a physician testified that he found no evidence of internal injuries on his examination of the plaintiff after his injury, 31 Permitting physicians to testify as experts concerning the condition of a person examined by them, and to base their opinion partly on the history of the case, held error. Smith v. St. L. & S. F. R. Co., 148 P. 759, 95 Kan. 151. A physician, while testifying as an expert, is not permitted to testify to his conclusions of the permanency of an injury to his patient based partially upon the history of the injury detailed to him by the patient or other person, and partially upon his own examination. Federal Betterment Co. v. Reeves, 84 l'. 560, 73 Kan. 107, 4 L. R. A. (N. S.) 460. A physician testifying as an expert should not be allowed to express an opinion as to the condition of the patient, formed in part upon the statements of third parties, or on what the family of the patient may have said to him. Chicago, R. I. & P. Ry. Co. v. Sheldon, 51 P. 808, 6 Kan. App. 347. 32 Ft. Smith & W. Ry. Co. v. Hutchinson (Okl.) 175 P. 922. 33 Chicago, R. I. & P. Ry. Cc. v. Jackson, 63 Okl. 32, 162 P. 823. Physician, who examined patient shortly after accident for purpose of testifying as an expert, could base his opinion on patient's subjective and objective symptoms, relying on history of case, including fact of accident, as circumstance on which he reached conclusion. St. Louis & S. F. Ry. Co. v. McFall, 63 Okl. 124, 163 P. 269. Refusal to permit a physician who examined plaintiff for the first time more than two years after the injury to testify that he thought a fistula in ano, from which he found the plaintiff suffering, was caused by traumatic injury held not error. Ballard v. Kansas City, M. & O. Ry. Co., 148 P. 764, 95 Kan. 343. 34 Roark v. Greeno, 59 P. 655, 61 Kan. 299, reversing judgment Greeno v. Roark, 56 P. 329, 8 Kan. App. 390. and on cross-examination was asked if he had not told plaintiff shortly after the injury that he was injured internally, and he denied it, impeaching testimony by the plaintiff is admissible.35 Where an expert witness founds his opinion on standard medical authorities, such authorities may be read to him on cross-examination, and he may be asked whether he agrees with same.38 Where the fees paid to an attorney constitute a demand chargeable to another, the special facts showing the importance of the case in which the fees were charged may be proved, and a hypothetical question as to the value of the services, based thereon, may be asked of a qualified witness.37 Where the evidence is not in material conflict and constitutes a sufficient predicate for an opinion as to the value of the services of attorneys, a witness who has heard all of the evidence may state an opinion based thereon as to such value, without the usual hypothetical question embodying a statement of the premises for the opinion being propounded to him.38 In an action for attorney's fees, an attorney testifying as an expert can be cross-examined upon the subject of his own charges in similar cases.39 § 1064. Handwriting The genuineness of a disputed signature may be proved by a comparison thereof with signatures of the same person on other instruments which are admitted or proved to be genuine; 40 but the genuineness of the writing or signature made the basis of comparison, and sometimes called the standard writing, must be 35 Monckton v. St. Louis & S. F. R. Co., 139 P. 1164, 92 Kan. 158. 36 Stout v. Bowers, 154 P. 259, 97 Kan. 33. 37 Tullock v. Mulvane, 60 P. 749, 61 Kan. 650, judgment reversed 22 S. Ct. 372, 184 U. S. 497, 46 L. Ed. 657. 38 Colley v. Sapp, 44 Okl. 16, 142 P. 989, judgment affirmed on rehearing 44 Okl. 16, 142 P. 1193. 39 Cooper v. Harvey, 94 P. 213, 77 Kan. 854. In an action for attorney's services, the cross-examination of an attorney testifying as an expert, as to his recommendation of what ought to be paid by defendant by way of compromise, was proper to probe the witness and to show how his judgment upon the question at issue was formed, and was not objectionable as evidence, the purpose and effect of which was to show an offer of compromise. Cooper v. Harvey, 94 P. 213, 77 Kan. 854. 40 Holmberg v. Johnson, 25 P. 575, 45 Kan. 197. proved by direct or positive evidence, and cannot be established by comparison. 41 One engaged in a business which necessitates the frequent comparison of handwritings, and who has been in the habit of making such comparisons, is qualified to testify to the genuineness of a disputed signature by comparison with others admitted to be genuine. 42 It is error to permit the witnesses on cross-examination to be asked their opinion as to the genuineness of several purported signatures of the same person, and afterwards to permit testimony showing that some of the purported signatures are false.43 It is error to present to plaintiff's witnesses, who are called as experts, false signatures for the purpose of testing the ability of the witnesses to detect a forgery, and to cross-examine such witnesses as to such false signatures, and then prove by another witness the fact that he wrote them himself.44 § 1065. In general DIVISION VII. HEARSAY Hearsay testimony, when properly objected to, is not admissible." 45 A request that a witness state a fact as to a certain choice or election does not call for a hearsay opinion." 46 41 Archer v. United States, 60 P. 268, 9 Okl. 569. Writings used as a basis for comparison of handwriting on cross-examination must be admitted to be genuine or clearly proved to be so, the same as on direct examination. Gaunt v. Harkness. 36 P. 739, 53 Kan. 405, 42 Am. St. Rep. 297. In an action involving the validity of a chattel mortgage, where a property statement purporting to have been signed by the mortgagors is offered in evidence, and the signature to it is denied, it is error to enter into an inquiry into the genuineness of letters purporting to have been signed by the mortgagors, to be used as a basis of comparison by experts with the signature to the property statement. Gilmore v. Swisher, 52 P. 426, 59 Kan. 172. 42 Ort v. Fowler, 2 P. 580, 31 Kan. 478, 47 Am. Rep. 501. 43 Underwood v. Quantic, 116 P. 361, 85 Kan. 111. 44 Gaunt v. Harkness, 36 P. 739, 53 Kan. 405, 42 Am. St. Rep. 297. 45 Chicago, R. I. & P. Ry. Co. v. Boring-Kim Produce Co., 57 Okl, 495, 157 P. 351; McKinney v. State (Okl. Cr. App.) 198 P. 108. 46 Beckman v. Ash, 103 Kan. 437, 173 P. 920. On request to witness to state fact as to a certain choice or election, answer that plaintiff's attorney elected to take a money judgment, instead of |