ORMOND, J.
Whether a witness, whose opinions are of*650fered to be given in evidence as an expert, in any art, or science, is competent to testify, depends upon his skill in the art or science. This, like all other questions of the competency of witnesses, is determined by the court; and in ascertaining the fact, the court may examine the witness himself, or may ascertain it from the testimony of others. One who exercises an art, or trade, is supposed to be acquainted with it. Thus a practising physician would be presumed, from that circumstance alone, to be acquainted with -the cause, and cure of diseases; but it by no means follows, that one who is not in the actual practice of medicine, may not be skilled in the science, so as to be able to give correct opinions, as to the existence, or cause of disease. Clinical practice, is doubtless a most efficient mode of acquiring such knowledge, by enabling, the practioner, from his own observation, to verify the assertions, or theories of others, or to correct errors into which they may have fallen; and it may be, that medical opinions, not brought to this test, are not worthy of much reliance as the basis of the verdict of a jury. But, if one asserts an ability to give correct opinions, upon any art, or science, from an acquaintance with the subject, acquired by observation and study, we cannot perceive on what ground he can be rejected, because he has not been in the actual practice of his profession. This circumstance, as already observed, may deprive his testimony of much weight with the jury, but is no ground for excluding it. So also, among physicians in actual practice, superior skill, greater power, or opportunity for observation, may entitle the opinions of one, to much greater weight than those of another, although both are equally competent, in legal estimation.
It results from what has been said, that the court did not err in permitting the witness to testify, he having stated that he had studied the science of medicine, and felt competent to express a medical opinion upon the diseases of women. A kindred aspect of this question, was discussed by this court, in Washington v. Cole, 6 Ala. 212" court="Ala." date_filed="1844-01-15" href="https://app.midpage.ai/document/washington-v-cole-6502152?utm_source=webapp" opinion_id="6502152">6 Ala. 212; and see also the case of Milton v. Rowland, at the present term, and The Commonwealth v. Mendurn, 6 Rand. 709.
But we think the court erred in permitting Dr. Guild t® testify to the jury, as to the competency of the witness to ex*651press correet medical opinions. The fact, that the witness who had been permitted to give his opinions, upon questions of medical science, had been a practising lawyer for sixteen years previous, was probably urged to weaken the' force of his testimony with the jury, and the object of introducing Dr. Guild, was manifestly to add weight to the opinions of the witness, by superadding the opinion of a well known practitioner, that the witness was qualified, to draw correct conclusions, on such questions. This was evidently invading the province of the jury, whose peculiar duty it was, to determine on the weight, the testimony of the witness was entitled to. Such testimony would have been properly adduced to the court, to establish the competency of the witness, but after he was admitted to testify, the jury were the exclusive judges of the credit he was entitled to.
In Washington v. Cole, supra, we held, that after a witness had been permitted to testify as a physician, evidence tending to show he was not a physician, but had merely lived in a drug store, was inadmissible testimony to the jury. The reason is precisely the same, where an attempt is made to fortify the claim of a witness to be considered an expert, by the opinions of others. If this were allowed, the verdict of the jury would possibly be rendered, not upon the credit they gave the witness as an expert, from the internal evidence afforded by his testimony to form correct medical opinions, but from the opinion of another witness of his skill and ability. This would be to substitute the witness for the jury, and investing him with the power of drawing conclusions for the jury.
Let the judgment be reversed, and the cause remanded.