Baker v. McGary Transportation Co., 140 Me. 190, 36 A.2d 6; Rouse v. Scott, 132 Me. 22, 164 A. 872. Also, where a father is plaintiff, seeking to recover for expenses and loss of minor's services, if there is contributory negligence on the part of the son it bars the father from recovery. Bonefant v. Chapdelaine, 131 Me. 45, 51, 158 A. 857. It should appear from the circumstances that the defendant was negligent and that the plaintiff was using due care. `If the result was produced by a commingling of the negligence of the two parties, the plaintiff cannot recover.' Lesan v. Maine Cent. Railroad Co., 77 Me. 85, 87; White v. Michaud, 131 Me. 124, 128, 159 A. 570; Eaton v. Ambrose, 133 Me. 458, 180 A. 363. The standard of measurement for both parties is, therefore, the care and caution exercised by a person who is ordinarily prudent and thoughtful. One who falls below this level, when in dangerous circumstances, is negligent.

In Howe v. Houde, 137 Me. 119, the action was by passenger against auto driver, "different conclusions may be drawn from the evidence." In Gould v. Transportation Co., 136 Me. 83, a substance came through open window of bus into passenger's eye. Negligence of company was question for jury. So also there were questions for the jury in Frye v. Kenney, 136 Me. 112, auto accident; Gerrish v. Ferris, 138 Me. 213, pedestrian struck on highway; Searles v. Ross, 134 Me. 77, mowing machine cut a boy who was asked to "touch up horses;" White v. Michaud, 131 Me. 124, where collision of automobile and motor cycle. There is no proof of facts that show breach of duty on the part of the defendant District toward this plaintiff. It does not appear that this cover was in the limits of the highway, or that pedestrians might be expected to walk there. The manhole was placed to contain meters, one of which was for the girl scout building.

Bonefant v. Chapdelaine, 131 Me. 45, 51. It should appear from the circumstances that the defendant was negligent and that the plaintiff was using due care. "If the result was produced by a commingling of the negligences of the two parties, the plaintiff cannot recover." Lesan v. Railroad Co., 77 Me. 85, 87; White v. Michaud, 131 Me. 124, 128; Eaton v. Ambrose, 133 Me. 458. The standard of measurement for both parties is, therefore, the care and caution exercised by a person who is ordinarily prudent and thoughtful. One who falls below this level, when in dangerous circumstances, is negligent.