Braley, J.
The plaintiff’s intestate, a sheet metal worker, while in one of the penthouses on the roof of a building in process of construction, fell through a ventilating duct or vent leading to the ground floor, dying shortly after his injuries without conscious suffering. A verdict was ordered for the defendant at the close of the plaintiff’s evidence, and the case is here on the report of the presiding judge. It being conceded, that due notice of the time, place and cause of the accident was given, only the questions of the due care of the decedent and the defendant’s negligence are presented.
By St. 1909, c. 514, §§ 127, 129, under which the action is brought, the plaintiff must introduce some evidence that her intestate was in the exercise of due care. The jury could have *538found, that on the day of the accident there were three benches in the house in question where he and other workmen were engaged in making metal cornices for the penthouses. The ventilating shafts or ducts, made of thin galvanized iron bolted together in sections, ran into the house where they remained in an unfinished condition with the sides or edges projecting above the floor. The door of the house on the side where the intestate’s bench was' placed had been securely nailed, and the only feasible access to the bench, as the jury could have found, was to enter from the unfastened door on the other side, and pass over the ducts across which planks had been laid, which the workmen used in passing from one side to the.other of the house. The intestate having finished a cornice, the fastened door was pried open and the cornice taken out to be placed in position. It was laid on the roof before being put up, and the defendant’s foreman, one Cox, having been called to another part of the work, said to the intestate, “You can take up where I have left off on my cornice,” which was at the bench near the unfastened door. The intestate, however, continued at work putting the cornice in place, and no further account of his movements is given except that one witness saw him working at Cox’s bench. It appeared in evidence, that he previously had used the planks, and an examination after his death showed, that, not having been bolted, the sides of the last section of the duct had “sprung” or bent in, the planks had been knocked or thrust off, and a short plank which had been over the duct at the centre was found on the floor below. The facts, that the intestate was found head downward at the bottom of the duct with the plank beside him, that the section of the .duct was bent down, the improvised bench which he had just used, consisting of two barrels and planks across them, overturned and the tools scattered over the floor, would lead fairly to the inference that in some way he had passed on to the planks which had given way under his weight. It is urged by the plaintiff, that the accident must have happened in the course of his employment as he passed across to get his tools. But no one saw him enter the penthouse, and there is nothing to indicate that through his own inadvertence while moving within the restricted space at the bench he may not háve fallen or stumbled in some way upon the planking, causing the giving way of the duct and the tilting of the short plank. *539The deplorable character of the misfortune is apparent, and the counsel for the plaintiff contends, that proof of the absence of all fault is sufficient to exclude the conception of negligence. Prince v. Lowell Electric Light Corp. 201 Mass. 276, and cases cited. The difficulty with this position is, that what occurred between the time when he was last seen alive and the time when his body was found at the foot of the shaft is wholly a matter of conjecture, where one hypothesis as to what he did is as good as another, and therefore no inference of due care can be drawn affirmatively, Ralph v. Cambridge Electric Light Co. 200 Mass. 566. French v. Sabin, 202 Mass. 240. Hamma v. Haverhill Gas Light Co. 203 Mass. 572. MacDonald v. Edison Electric Illuminating Co. 208 Mass. 199. Lydon v. Edison Electric Illuminating Co. 209 Mass. 529. Taylor v. Pierce Brothers, 213 Mass. 247.
W. W. Clarke, {C. J. Muldoon, Jr., with him,) for the plaintiff.
C. S. Knowles, for the defendant.
It is unnecessary to consider the question of the defendant’s negligence, and there must be judgment for the defendant on the verdict.
So ordered.