The case is not distinguishable in principle from Bennett v. Warren,70 N.H. 564. The plaintiff was inexperienced, did not know of the concealed danger, and was in the performance of what he reasonably thought to be a part of his duty. It might well be found that it was negligence to set a child at this work without any instruction or warning. The motions for nonsuit and that a verdict be directed for the defendants were properly denied.