(a,fter stating the facts). There were several departments in the defendant’s factory, over which one Phelps was the general superintendent. Each department had a foreman or manager — a man where there were men, and a woman where there were women or girls. Some of the principal foremen had subforemen under them. From the testimony introduced on the part of the plaintiff, it appears that Bordeau “had charge of the mason department on construction and repairs,” and that plaintiff’s son was a subforeman under him. There was also evidence tending to show that Bordeau sometimes hired and discharged men, and sometimes bought material for use in his department. His position and authority were no greater than were those of the mill foreman in Lepan v. Hall, 128 Mich. 523, or of the foreman in Mikolojczak v. Chemical Co., 129 Mich. 80. See, also, Wellihan v. Wheel Co., 128 Mich. 1. The true test in these cases is the character of the act, rather than the rank or grade of the employe. 4 Thompson on Negligence, § 4923. The vice principal, manager, or superintendent may become a fellow-servant, and a fellow-servant may become a vice principal. Id. § 4918. The true principle governing the *20cases is that, if the master cannot delegate the authority to perform the act, he is liable regardless of the rank of his employe. If, however, he may delegate the power to perform the act, he has performed his full duty to his employe when he has used due care to employ competent assistants, regardless of their rank, and to furnish a safe place and suitable appliances. Superiority of position is not the test. Id. § 4919. The act in turning on the blower was one of fellow service. It was not an act essential in carrying on the plaintiff’s business. The blowers were not used for the purpose of cooling the oven when employés were engaged in making repairs. They had never been so used. The employer had no reason to expect that they would be. Plaintiff himself testified that the only means before employed for cooling the ovens was to leave them open, if there was time for them to cool in this way, and, if not, then to use water from a hose. The master in this case is no more liable than it would have been if a stranger had turned on the blower. In such cases the person, whether employe or stranger, who does the negligent act, is alone responsible for its consequences. In turning on the blower, Bordeau was not acting for the master, or by virtue of any power delegated to him. If it was a negligent act, Bordeau alone is responsible for it. The case is ruled by Lepan v. Hall, and Mikolojczak v. Chemical Co., supra, and authorities there cited. See, also, 4 Thompson on Negligence, § 4921.
There is another feature of this case which, though not argued by counsel, would, if raised, have clearly prevented recovery. Plaintiff testified that he remained at the work for some minutes after he knew that the blower was to be turned on, and that he knew the purpose of turning it on. Though he testified that he did not know where the blower entered the oven, he is chargeable with knowledge of the physical law that the effect of turning a strong current of air into the oven would result in violently disturbing the dust and ashes. He had time to withdraw after he heard the statement of Bordeau, or to call to him not to turn *21the blower on. Instead, he chose to remain at his work. Under these circumstances, it is manifest that he assumed the risk.
Judgment affirmed.
Moore, C. J., and McAlvay, Blair, and Ostrander, JJ., concurred.