Smith If the underwriters are liable to refund, the plaintiffs are not bound to resort to them. That is the duty of Carrington. the defendants. * 67 V. The money being paid by the plaintiffs before the orders for insurance were countermanded, there can be no pretence that the plaintiffs are not entitled to re cover. 3. Remington was not a competent witness, because in a suit against him upon the bond, he might show that the whole amount for which he was liable had been paid; which he could not do if the plaintiffs had a right to apply the credit side of the account to discharge the money by them advanced for the premium. He was, therefore, directly interested in the event of the suit. 4. There was no proof that the paper offered as a copy of the defendant Carrington's letter to Smith & Ridgeway was a copy of the original, and, therefore, it ought not to have been received, nor was there any evidence offered of the hand-writing of Smith & Ridgeway to the paper purporting to be a letter from them. 5. The opinion of the court that reasonable notice was wholly a question of fact, was erroneous. We contend that in all mercantile cases, reasonable notice is a question of law. 1 T. R. 167. Tindall v. Brown. The court did not say of what or to whom notice was to be given. But the underwriters were not bound to refund without proof as well as notice. *Ingersoll, contra. 1. As to the competency of Remington. A witness cannot be excluded if he is competent to answer any question. 3 T. R. 27. Bent v. Baker. If the suit had been brought only for the premium of insurance, his competency would have been unquestionable. Shall it be in the power of the plaintiffs to deprive the defendants of their witness, by blending other matters of account in their action? Surely not. But here all the other items of the plaintiffs' account were expressly admitted by the defendants before they offered Remington as a witness; and he was offered as a witness to that one item only. 2. As to the copy of Carrington's letter, it is con Smith V. nected with that from Smith & Ridgeway, which the bill of exceptions states to be a letter from them to Car- Carrington. rington, purporting to be in answer to Carrington's letter to them. There was evidence that it was in his hand-writing, and that he had been absent in China for two years, so that he could not have fabricated it for the occasion. Where there is a connected correspondence, the whole ought to go to the jury. In mercantile cases, the rules of evidence are not so strict as in other cases. 1 Dall. 16, 17. Riche v. Broadfield. Park, 406. 2 Str. 1127. Russel v. Boehme. 3 Dall. 19. Bingham v. Cabot. 2 Dall. 384. 3. As to the opinion given and the opinion refused. The question is not yet settled whether a bill of exceptions will lie to an erroneous opinion given by the judge in his charge to the jury at the trial; or to a proper opinion prayed and refused. 3 Bl. Com. 372. MARSHALL, Ch. J. Is not the reason why the English books do not show such a case, because, upon a doubt as to the correctness of the opinion of the judge in his charge to the jury, a case is always made, and a new trial moved for, on the ground of misdirection? Ingersoll. If the court had given an opinion upon the reasonableness of the notice, it would have been *error, because it is a matter of fact. But here the prayer was, that the court should give an opinion as to the fact of notice, as well as to the reasonableness of notice. The expression "under the circumstances of the case" refers the matter of fact to the court. It calls upon the court to say what are the circumstances of the case, and, consequently, to decide, the weight of evidence, and to infer one fact from others, which is the peculiar province of the jury. The jury is certainly to decide the facts; whether upon those facts the notice is reasonable, may be matter of law; but in Pennsylvania, and perhaps in other states, it is usual to submit the whole question to the jury, the court giving them information as to such points of law as have been decided. If the facts are settled, the court may give instruction as to the law; but if the question of law cannot he abstracted from the question of fact, the whole must **68 Smith V. Carrington. *69 be submitted to the jury. 1 Dall. 255. Robertson v. Vogle. 2 Dall. 158. Bank v. M'Knight. 2 Dall. 195. Mallory v. Kirwan. P. B. Key, in reply, 1. Abandoned the objection to the admissibility of Remington as a witness." ter. 2. As to the copy of the defendant Carrington's let No man can make evidence for himself. 2 Vez. 42. A copy cannot be given in evidence until you have proved that the original existed, and is lost or destroyed, or not in the power of the party to produce; and then the copy must be proved by a witness who compared it with the original. It does not appear that the plaintiff admitted the paper supposed to be a letter from Smith & Ridgeway, to be genuine, and simply not denying is not admitting. But the plaintiff objected to both the copy and the letter, as appears by the whole tenor of the bill of exceptions. *3. As to the opinion prayed. The expression "all the circumstances of the case," means all the circumstances of the case stated in the bill of exceptions, and the evidence to which it refers. This was certainly proper. It was not praying the court to decide the facts, but only the law arising upon those facts. The court has a right to say that under the circumstances of the case, the law is so. MARSHALL, Ch. J. Does not that involve the verity of the facts? Key. The court can say that there was no evidence whatever of notice, and if so, that the plaintiffs had a right to recover. The question what is evidence is matter of law. But the court erred in submitting the whole question of reasonable notice to the jury. The reasonableness is matter of law. 2 Inst. 222. Co. Litt. 56.b. 1 T. R. 167. and 2 T. R. 186. Tindall v. Brown. February 16. MARSHALL, Ch. J. delivered the opinion of the court. This case comes up on exceptions to certain opinions given by the judges of the circuit court of Rhode Island, at the trial of the cause before them. The first exception is to the admission of Peleg Remington as a witness. This exception appeared to be abandoned by the counsel in reply, and is, indeed, so perfectly untenable, that the court will only observe, that Peleg Remington does not appear to have been interested in the event of the cause in which he deposed, but certainly was not interested in the particular fact to which he was required to depose, and was, therefore, clearly a competent witness. *The second exception is taken to the opinion of the court admitting as evidence a paper purporting to be the copy of a letter written by the defendant, Carrington, to Smith & Ridgeway, of Philadelphia, the correspondents of the plaintiffs, and also a letter from Smith Ridgeway to the defendant, Carrington, purporting to be an answer to the said letter. To the admission of the letter of Smith & Ridgeway no just objection appears. The verity of that letter is acknowledged on the face of the bill of exceptions, and no cause is stated why it should not have been read to the jury. But the admission of the copy of a letter written by one of the defendants stands upon totally different ground. To introduce into a cause the copy of any paper, the truth of that copy must be established, and sufficient reasons for the non-production of the original must be shown. If in this case the answer of Smith & Ridgeway had authenticated the whole letter of Carrington, the copy of that letter need not have been offered, since its whole contents would have been proved by the answer to it. If its whole contents were not proved by the answer, then the part not so proved was totally unauthenticated, and may have formed no part of the original letter. In this case, the answer cannot have authenticated the Smith V. Carrington. *70 Smith V. Carrington. 71 copy, because the bill states that the defendants gave no proof of its being true. This copy, therefore, not being proved to be a true copy, ought not to have gone before the jury. Into its importance or operation this court cannot inquire. It was improper testimony, and a verdict founded on improper testimony cannot stand. For this error the judgment must be reversed, and the cause remanded to the circuit court of Rhode Island, to be again tried. The third exception is taken to the refusal of the court to give an opinion on a question stated by the counsel for the plaintiffs. The difficulty of deciding on this exception does not arise from any doubt which *ought to have been produced by the facts in the cause, but from the manner in which the question was propounded to the court. After a long and complex statement of the testimony, the counsel for the plaintiffs requested the court to declare whether, "if the plaintiffs had actually paid the said premium to the underwriters, before any notice of the change of the destination of the ship, they had a right, under the circumstances of the case, to recover the same of the defendants." To this question the court refused to give an an swer. There can be no doubt of the right of a party to require the opinion of the court on any point of law which is pertinent to the issue, nor that the refusal of the court to give such opinion furnishes cause for an exception; but it is equally clear that the court cannot be required to give to the jury an opinion on the truth of testimony in any case. Had the plaintiffs' counsel been content with the answer of the court to the question of law, he would have been entitled to that answer; but when he involved facts with law, and demanded the opinion of the court on the force and truth of the testimony, by adding the words "under the circumstances of the case,' the question is so qualified as to be essentially changed; and although the court might with propriety have separated the law from the fact, and have stated the legal principle, leaving the fact to the jury, there was no obligation to make this discrimination, and, conse |