Opinion by
Mr. Justice Walling,
These appeals by plaintiffs are from the trial court’s refusal to take off a compulsory nonsuit in an action by husband and wife for personal injuries to the latter. The defendant, Dr. George E. Pfahler, has offices in Philadelphia where he and his assistants are engaged, inter alia, in taking and developing X-ray photographs. The wife plaintiff, Mrs. Sarah F. Nixon, while having X-ray photographs taken of her teeth in defendant’s offices on March 2, 1920, was injured by an electric spark which struck her right knee and passed down and out at her foot. Plaintiffs’ statement in general terms charged negligent construction, operation, etc., of the apparatus by which the photographs were taken. At the trial no evidence of negligence was offered, plaintiffs resting their case solely on proof of the accident. They did, however, call the defendant, as for cross-examination, and his uncontradicted testimony was, in effect, that his . offices were equipped in every respect with the best obtainable appliances and were at the time in charge of an experienced and skillful operator.
The X-ray exposure necessitates the passage of an electric current of small volume but very high voltage through a wire suspended about two feet above where the patient reclines. The defendant’s testimony was *379that this current would not jump more than approximately five inches, while Mrs. Nixon testified she did not raise her leg or otherwise come near the wire. Dr. Pfahler testified that some ten thousand photographs had been taken by the same apparatus without injury and that he had never known of a like accident except in one instance where a patient brought his hand close to the wire. What caused the electric current, in the instant case, to leap from the wire through the air to the plaintiff’s leg, as it seems to have done, is unknown. There was no evidence that such an accident could have been anticipated, or that it resulted on this occasion from any default on behalf of defendant. Plaintiffs make no claim of having shown any negligence, but on their behalf it is urged that negligence should be inferred from the happening of the accident. In other words, that the rule of res ipsa loquitur should be applied. We have applied that rule against carriers of passengers, and in other rare instances, but never against a medical practitioner, who is within the general rule that negligence will not be presumed from the mere happening of an accident. In the language of Mr. Justice Pell in Stearns v. Spinning Co., 184 Pa. 519, 523: “Excepting where contractual relations exist between the parties, as in the case of carriers of passengers and some others, negligence will not be presumed from the mere happening of the accident and a consequent injury, but the plaintiff must show either actual negligence or conditions which are so obviously dangerous as to admit of no inference other than that of negligence.” It is well settled that an action against a physician for malpractice can be sustained only by proof of his negligence, and that the burden of such proof rests upon him who asserts it: English v. Free, 205 Pa. 624; Williams v. LeBar, 141 Pa. 149; Wohlert v. Seibert, 23 Pa. Superior Ct. 213; Napier v. Greenzweig, 256 Fed. 196. That this is not changed because the practitioner uses an X-ray instrument is expressly decided in the very recent case *380of Stemons v. Turner, 274 Pa. 228, 26 A. L. R. 727, 732. That case rules the present, for in each electricity was employed in an X-ray machine to accomplish a desired result, and the rule of evidence would not shift because of the exact nature of the injury such agency inflicted. The X-ray machine is indispensable to the healing art and the mere happening of an accident from its use creates no presumption against the instrument or its operation. It is necessary for those engaged in the medical profession to constantly employ dangerous agencies, like electricity, radium, surgical instruments, poisons, anesthetics, etc., and if prima facie liability attaches for an accident resulting from the use of one, logically it should from the use of any other, and the practitioner employing such would be practically an insurer of the safety of his patients, which the law declares he is not. The question of liability does not hinge upon the dangerous character of the agency employed, but upon the manner of its use, as to which the presumption of due care is in favor of the practitioner, until overcome by evidence to the contrary.
A distinction is sought to be made between the Stemons case and the present on the ground that there the injury was to the part of the body at which the instrument was directed, while here it was not. But the transmission of an electric current is a necessary part of X-ray work and cannot be separated from the operation so as to constitute a distinct act and cast upon the operator the burden of proving care in its use. Undoubtedly the negligence of a physician may be shown by circumstantial evidence, as it may in other cases, but nothing appears here except the happening of the accident, which, as above stated,. is insufficient. Furthermore, the evidence submitted shows the exercise of proper care on behalf of defendant. So far as appears, the unfortunate occurrence now under consideration, was purely accidental and the trial court properly so held.
The order discharging the rule to take off nonsuit is affirmed.