1. Where a servant sues his master for damages for personal ■injuries, the burden is on the plaintiff to show not only negligence on the part of the master, but due care on his own part; and it must appear that the plaintiff did not know, and had not equal means of knowing, all that which is charged as negligence, and that by the exercise of ordinary care he could not have known thereof. Civil Code (1910), § 3131; Ludd v. Wilkins, 118 Ga. 525, 526 (45 S. E. 429), and citations.
2. “The general rule of law declaring the duty of a master in regard to furnishing a servant a safe place to work is usually applied to a permanent place, or one which is quasi permanent. It does not apply to such places as are constantly shifting and being transformed as a direct result of the servant’s labor, and where the work in its progress necessarily changes the character for safety of the place in which it is performed, as it progresses.” Holland v. Durham Co., 131 Ga. 715 (1) (63 S. E. 290); L. & N. R. R. Co. v. Dunn, 21 Ga. App. 379 (1) (94 S. E. 661), and citations.
3. Where a petition sets out a cause of action, and the plaintiff proves *244every fact charged, but where, on cross-examination or otherwise, his right to recover is disproved by the establishment of the existence of other undisputed defensive facts, which show that he is not entitled to a verdict, then a nonsuit should be awarded. Evans v. Mills, 119 Ga. 448 (2) (46 S. E. 674); Evans v. Scofield’s Sons Co., 120 Ga. 961 (48 S. E. 358) ; Woods v. Mercantile Bank & Trust Co., 32 Ga.. App. 106 (122 S. E. 819).
Decided April 14, 1926. Porter & Mebane, for plaintiff. Maddox, Matthews & Owens, for defendant.4. The eases cited and relied on by counsel for the plaintiff in error are distinguished by their particular facts from the instant ease and from the cases cited above.
5. Under the above-stated rulings and the facts of this case, the court did not err in awarding a nonsuit.
Judgment affirmed.
Luke, J., concurs. Bloodworth, J., not participating, on account of illness.