David Josiah Brewer

“ He had made out from them a statement of facts respecting the workings of the mill from October 18th to the 7th of November, which he had forwarded to the plaintiff, and the details of that statement, as verified by the books, were the sum and substance of his testimony. After he had finished, and the plaintiff had rested in his rebuttal, the defendant called a witness named Hall, who testified that he had examined the books, and he was then asked what the average run per hour was for the months of November, December, and January, separately, as shown by those books. ”

“ The general manager of the defendant was asked what, in his judgment, was the daily capacity of the mill. This question was objected to, on the ground that the witness was not shown to be competent to testify as an expert, which objection was sustained. How much knowledge a witness must possess before a party is entitled to his opinion as an expert is a matter which, in the nature of things, must be left largely to the discretion of the trial court, and its ruling thereon will not be disturbed unless clearly erroneous. Manufacturing Co. ”

“ He does not appear to have been a practical machinist, or to have had any special knowledge of mining or crushing machinery. He was not superintendent of the workings of the mine or of the machinery, and does not claim to have been there regularly, or, indeed, oftener than once a week, and, as general manager, was apparently more employed in the financial and outside business affairs of the company than in the details of the mining or the practical workings of the machinery. We think the ruling of the trial court in excluding his opinion was right ”