[1-3] Defendant Railroad was under a duty to give timely warning when its train approached the visually obstructed and much traveled Rose Street crossing. Cox v. Gallamore, 267 N.C. 537, 148 S.E. 2d 616; Jarrett v. R. R., 254 N.C. 493, 119 S.E. 2d 383; High v. R. R., 248 N.C. 414; 103 S.E. 2d 498; Summerlin v. R. R., 238 N.C. 438, 78 S.E. 2d 162; 6 Strong, N. C. Index Railroads § 6 (2d ed. 1968). Assuming the truth of plaintiffs’ evidence, as we must in passing upon a motion for nonsuit, it would justify a finding by the jury that defendant failed to give any warning as its locomotive approached the crossing. Kinlaw v. R. R., 269 N.C. 110, 152 S.E. 2d 329. Plaintiffs’ evidence establishes the negligence of Mrs. Phillips. With full-knowledge of the obstructed crossing, she drove toward it *401at an undiminished speed of 30-35 MPH. Carter v. R. R., 256 N.C. 545, 124 S.E. 2d 561; Summerlin v. R. R., supra.
 On this evidence the negligence of the driver cannot be imputed to plaintiffs’ intestates, and they were guilty of no contributory negligence. Harper v. R. R., 211 N.C. 398, 190 S.E. 750; Johnson v. R. R., 205 N.C. 127, 170 S.E. 120; 6 Strong, N. C. Index Railroads § 7 (2d ed. 1968). Therefore, unless Mrs. Phillips’ negligence relieves defendant Railroad from liability, the judgments of nonsuit were erroneously entered. Defendant contends that even if plaintiffs’ evidence shows it to have been “in some respect negligent,” it also shows the death of plaintiffs’ intestates to have been “independently and proximately produced by the wrongful act, neglect or default of a responsible third person, to-wit: Mrs. Phillips, the operator of the pickup truck.” In support of this proposition, defendant relies, inter alia, upon Jones v. R. R., 235 N.C. 640, 70 S.E. 2d 669; Hinnant v. R. R., 202 N.C. 489, 163 S.E. 555, and—most heavily—upon Jeffries v. Powell and Branch v. Powell, 221 N.C. 415, 20 S.E. 2d 561.
Jeffries v. Powell and Branch v. Powell, supra, were suits against a railroad by the driver of an automobile and the administrator of his deceased passenger. The driver was injured and the passenger killed when a train struck the vehicle at a grade crossing. Plaintiffs’ evidence tended to show that the “whistle didn’t blow and the bell didn’t ring.” In affirming judgments of nonsuit, Winborne, J. (later C.J.), said: “[I]t is clear from the evidence that the negligence of Branch (the driver) was such as to insulate the negligence of defendants, and that his negligence was the sole proximate cause of the collision between his automobile and the train of defendants in which Jeffries lost his life.” In concluding the opinion he quoted from Chinnis v. R. R., 219 N.C. 528, 531, 14 S.E. 2d 500, 502: “Conceding that there was evidence of failure on the part of defendant to sound whistle or bell to give warning of the approach of the train to the crossing, it is clear that the active negligence of the driver of the automobile, subsequently operating, was the real efficient cause of the injury to plaintiff’s intestate. . . . The negligence of the driver of the automobile was patent. It intervened between the failure of the defendant to give warning of the approach of the train to the crossing and the injury to plaintiff’s intestate, and it began to operate subsequent to any act of negligence on the part of defendant, and continued to operate to the instant of injury.”
Plaintiffs in the instant case, contending that intestates’ deaths were proximately caused by the joint and concurring negligence of defendant Railroad and the driver of the truck, rely, inter alia, upon *402 Cox v. Gallamore, 267 N.C. 537, 148 S.E. 2d 616; Henderson v. Powell and Rattley v. Powell, 221 N.C. 239, 19 S.E. 2d 876; Harper v. R. R., 211 N.C. 398, 190 S.E. 750; Johnson v. R. R., 205 N.C. 127, 170 S.E. 120.
In Henderson and Battley, supra, two passengers were injured, one fatally, when McCrimmon, the operator of the automobile in which they were riding, drove upon a blind crossing over a much used public street. There was no watchman or automatic signaling device to give warning of an approaching train. The driver testified that he stopped his car, looked and listened. Then, seeing nothing and hearing no whistle, bell, or signal, he drove upon the tracks and was struck by a speeding train. The trial judge nonsuited the plaintiffs, who appealed. In overruling the nonsuit and disposing of defendant’s contention that “the intervening negligence” of the driver of the car “insulated” the defendant’s negligence and became the “sole proximate cause,” Seawell, J., speaking for the Court, reasoned: “It took the combined activities of the railroad company and Mc-Crimmon to bring their respective vehicles into the collision. . . . The formula proposed by defendants would exonerate both of them with equal impartiality.” The duties of the railroad and those using the crossing “are reciprocal, interrelated, and immediate; and, whatever the previous history of neglect, are concurrently in force and effect as soon as the zone of danger is created by simultaneous approach to the intersection.” No negligence is “insulated” so long as it plays a substantial and proximate part in the injury. The legal effect of the active negligence of two independent agencies, simultaneously occurring, and inflicting injury upon a third person hinges upon the question of foreseeability. The test is whether the intervening act and the resultant injury is one that the original actor could have reasonably foreseen and expected. The negligence of McCrim-mon was not “of such an extraordinary character as to be beyond the limits of foreseeability.”
As opinion writers have frequently noted, cases involving grade-crossing accidents are myriad, and “no good can be obtained from attempting to analyze the close distinctions drawn in the decisions of these cases for each case must ... be governed by the controlling facts there appearing.” Fairdoth v. R. R., 247 N.C. 190, 193, 100 S.E. 2d 328, 331, and Hampton v. Hawkins, 219 N.C. 205, 209, 13 S.E. 2d 227, 229. Gilliam, District Judge, put it succinctly: “Any effort to reconcile the North Carolina law on the subject of insulating negligence seems futile.” Cronenberg v. United States, 123 F. Supp. 693, 699.
*403Prosser, in his treatise on Torts § 51 (3d ed. 1964) analyzes the problems of intervening causes with his usual clarity. Except when quoted, we summarize pertinent portions of his discussion:
The question is not one of actual causation because the problem never arises until causation is established. The query is “whether the defendant is to be held liable for an injury to which he has in fact made a substantial contribution, when it is brought about by a later cause of independent origin. . . . The older cases tend to ask the question, why should the defendant be held liable for harm brought about by something for which he is not responsible? The later ones tended to ask instead, why should he be relieved of liability for something that he has caused, along with other causes?” Since an infinite number and variety of causes may intervent after the defendant’s negligence is an accomplished fact, “out of sheer necessity and in default of anything better,” the courts have had “to fall back upon the scope of the original foreseeable risk which he has created.” They say, therefore, that the defendant is to be held liable only if the intervening cause is foreseeable. “If the intervening cause is one which in ordinary human experience is reasonably to be anticipated, or one which the defendant had reason to anticipate under the particular circumstances, he may be negligent among other reasons because he failed to guard against it; or he may be negligent only for that reason.” If it be determined “that the defendant’s duty requires him to anticipate the intervening misconduct, and guard against it, it follows that it cannot supersede his liability.”
There are many situations in which the reasonably prudent man is expected to anticipate and guard against the conduct of others. Prosser, supra, § 33. “[H]e is required to realize that there will be a certain amount of negligence in the world. In general, where the risk is relatively slight, he is free to proceed upon the assumption that other people will exercise proper care. . . . But whén the risk becomes a serious one, either because the threatened harm is great, or because there is an especial likelihood that it will occur, reasonable care may demand precautions against ‘that occasional negligence which is one of the ordinary incidents of human life and therefore to be anticipated.’ ‘It is not due care to depend upon the exercise of care by another when such reliance is accompanied by obvious danger.’ Thus an automobile driver may not proceed blindly across a railway track, upon the assumption that any approaching train will sound bell and whistle. . . .” Prosser, supra at p. 174. Conversely, even though the train crew knows that a motorist approaching a railroad crossing is charged with the duty of keeping a *404vigilant lookout for an approaching train, it likewise has the duty to keep a lookout for the motorist and to give a timely warning of the train's approach. Johnson v. R. R., 255 N.C. 386, 121 S.E. 2d 580.
[5, 6] We think “ordinary human experience” demonstrates that a train crew should reasonably foresee that the driver of an automobile nearing a railroad crossing may be unaware of the train’s approach and drive upon the track unless he receives timely warning that the train is coming. Inattention on the part of the operator of a motor vehicle is all the more likely if the crossing is obstructed, little used by the railroad and much used by the public. A railroad’s failure to protect the traveling public against that very risk is negligence. “Foreseeable intervening forces are within the scope of the original risk, and hence of the defendant’s negligence. The courts are quite generally agreed that intervening causes which fall fairly in this category will not supersede the defendant’s responsibility.” Prosser, supra, § 51, p. 312. This is the rationale of Henderson and Rattley, supra, and of Cox v. Gallamore, supra.
 At this stage of the proceedings, only plaintiffs’ evidence has been heard. We express no opinion as to its veracity or the inferences which arise from it. We merely hold that plaintiffs’ evidence was sufficient to support a finding that defendant failed to signal the approach of its train to the crossing and that its negligence concurred with that of Mrs. Phillips in proximately causing the deaths of plaintiffs’ intestates. The judgment of nonsuit is
MooRE, J., did not participate in the consideration or decision of this case.