The sole question is whether the trial court erred in refusing to include in the special verdict a question requested by defendant relating to plaintiff’s assumption of the unusual risk attending the work arising from the negligent conduct of Paratulla. This action is brought under the federal Employers’ Liability Statute and, consequently, the negligence of a fellow-servant constitutes no defense to the action. However, it appears from plaintiff’s testimony that Paratulla, upon several occasions prior to the accident, had pulled upon his pick before plaintiff was ready; that this incident had occurred upon sufficiently nu*243merous occasions to acquaint plaintiff with the negligent disposition of ' Paratulla in this respect, and respondent contends that, by continuing the employment after such knowledge, the plaintiff assumed the unusual risk arising from Paratulla’s conduct in pulling upon the pick before plaintiff was ready. It is well settled that assumption of the risk does constitute a defense under the federal Employers’ Liability Act.

In accepting employment an employee may presume that his fellow-servants are competent and careful, and he does not assume the risk of their unexpected negligent acts. 1 Shearman & Redf. Neg. (6th ed.) § 207g; Graber v. D., S. S. & A. R. Co. 159 Wis. 414, 150 N. W. 489; Ewig v. C., M. & St. P. R. Co. 167 Wis. 597, 167 N. W. 442, 169 N. W. 429. But it is well settled that an employee who continues at work without protest with knowledge of the fact that he is exposed to extraordinary hazard by reason of a defective appliance or machine, thereby assumes such unusual risk. By the same token, where an extraordinary hazard arises by reason of the negligent manner in which a co-employee does his work, and the employee with full knowledge of such negligent disposition on the part of his co-employee continues at work without protest, he assumes the unusual risk thus created. Of course there is a difference between a defective machine and a negligent co-employee in this: a defective appliance or machine will remain defective until repaired and the risk arising from its use will be constant. A co-employee may be negligent upon one occasion only and thereafter properly perform his task or duty. His .negligent acts may be of frequent or infrequent occurrence. The mere fact that he is negligent upon one occasion does not necessarily imply that he will be negligent upon future occasions. But it is apparent that they may be of such frequent occurrence as to charge persons of reasonable care and prudence with knowledge that it is dangerous to work with him. Where such is the case, *244and his co-employees, notwithstanding such knowledge, continue in the employment without protest, they assume the risk arising from his negligent practices as well as the risk arising from the continued use of a defective appliance or machine. Of course it is ordinarily for the jury to say whether his negligent practices have been of such frequent occurrence in the past as to charge men of reasonable care and prudence similarly situated with knowledge of the extraordinary or unusual risk or danger arising to those who are working with him. Where such is found to be the fact, then it follows as a matter of law that those who continue to work with him as his co-employees assume the extraordinary or unusual risk of the employment arising from his negligent tendencies.

In this case the jury would have been warranted in finding from plaintiff’s testimony that upon numerous occasions in the past Paratulla had prematurely pulled upon his pick; that such occasions were so numerous as to charge a person of ordinary care and prudence similarly situated with the fact that Paratulla’s disposition and practices in such respect constituted an unusual or extraordinary hazard of the work. Had the jury so found, they would have been warranted in answering the question requested by the defendant in the affirmative, which would have defeated plaintiff’s right to a recovery. The trial court erred in its refusal to submit the question, and a new trial was properly granted by the circuit court.

By the Court. — Order affirmed.