Mr. Justice Gabbert
delivered the opinion of the court.
.Counsel for appellant assign as error the. giving and refusal of instructions ; admitting evidence regarding the custom of carrying a red light in the cupola; submitting the special interrogatories, because leading and not based upon the evidence.
The propositions raised by appellant on the errors assigned, except that relating to the leading character of the special interrogatories submitted, are dependent for solution upon what the evidence tends to establish, or does establish, on these questions: First, what was the proximate cause of the accident ? Second, was this cause the negligence of appellant ? There is also presented these legal propositions : Did the negligence of the employees of the freight train, in leaving the switch open, and giving the affirmative signal that *23the track was clear, relieve appellant from responsibility for its negligence, if negligence upon its part was established ? And, should the cause, under .the evidence, have been submitted to the jury ? But before proceeding with a discussion of the evidence bearing on the vital questions in the case, the rules of law by which these questions, and their materiality, must be determined, will first be stated. When the facts are undisputed and are susceptible of but one inference, the question whether a certain act is the proximate cause of an injury, is one of law for the court (Henry v. St. L., K. C. & N. R. Co., 76 Mo. 288; Pike v. G. T. R. Co., 39 Fed. Rep. 255), but ordinarily the question of what was the proximate cause of an accident is a question of fact to be determined by the jury, from the evidence, under appropriate instructions by the court. D., T. & G. R. R. Co. v. Robbins, 2 Colo. App. 313; Mil. & St. P. R. Co. v. Kellogg, 94 U. S. 469; Hayes v. Williams, 17 Colo. 465; Mo. M. & I. Co. v. Rees, 21 Colo. 435.
Proximate cause is defined as “ that cause which, in natural and continued sequence, unbroken by any efficient intervening cause, produced the result complained of, and without which that result would not have occurred.” Lutz v. A. & P. R. Co., 53 Am. & Eng. R. R. Cases, 478; 16 Am. & Eng. Ency. of Law, 436; or “ that cause which immediately precedes and directly produces an effect, as distinguished from a remote, mediate, or predisposing cause.” B. & M. R. Co. v. Budin, 6 Colo. App. 275.
It is the duty of an employer to make reasonable efforts to keep machinery and appliances used by. his employees in suitable ■ condition for use. This is one of the duties which he is bound to perform, and cannot be delegated, so as to exonerate him from liability to an employee who is injured by the negligence of a coemployee charged with the performance of such duty, in failing to do so ; for the employee so charged is the representative of the employer, and not a co-servant with the one who sustains an injury by the negligent performance of such duty, and the act or omission of the *24employee in this respect is that of the employer, irrespective of the grade of the employee whose negligence caused the injury. Wells et al. v. Coe, 9 Colo. 159; McKinney on Fellow Servant, § 32; Braun v. C. R. I. & P. Ry. Co., 53 Iowa, 595; N. P. Ry. Co. v. Herbert, 116 U. S. 642; Corcoran v. Holbrooke, 59 N. Y. 517; Fuller v. Jewett, 80 N. Y. 47.
If the negligence of the master is the proximate cause of an injury to an employee, he is not relieved from responsibility, because the negligence of a coemployee contributed to such injury. McKinney on Fellow Servant, § 31; Grand Trunk R. Co. v. Cummings, 106 U. S. 700; Town v. Mich. C. R. Co., 47 N. W. Rep. 665; Cone v. Del., L. & W. R. Co., 81 N. Y. 206; Cayzer v. Taylor, 10 Gray, 274; Thompson on Negligence, note 10, p. 981.
The engine upon which deceased was employed was derailed by the open switch, which was left in that condition by the neglect of the employees on the freight train. The affirmative signal given by the fireman on the engine of the freight, that the track was clear, was also negligence; but all these acts were those of coemployees of deceased, and, as held in the previous decision of the case by this court, for such negligence the company is not responsible, and it therefore becomes necessary to inquire whether or not the evidence discloses any negligence on the part of appellant which directly contributed to the result which followed the negligent acts of the employees of the freight train. The claim of appellee is that the absence of the cupola light was due to the negligence of appellant, and that its presence would have prevented the accident.
The rules require that two or more red lights shall be carried on the rear of each freight train after sunset; that when a freight is sidetracked for the purpose of allowing another to pass on the main track, these lights must be turned or removed, and green displayed toward the expected train as soon as the track is clear, i. e., the switch reset. In order to comply with this rule as a signal to a train approaching from the rear, the tail lights would be turned so as to display *25green toward the expected train, and if a red light was carried in the cupola, it would he necessary to remove that before the engineer of the approaching train would understand that the track was clear, for with a red light displayed in the cupola, although the tail lights displayed green, he would be warned that something was wrong, because the signals were not right, and, red signifying danger', would signal him to stop. The employees of a train approaching from the front could not see the red tail lights, but could see one in the cupola; they would also see the green displayed by the inside tail light, which, alone, would indicate that the track to the .rear was safe; but with the red from the cupola, they would understand that something was wrong, because, under the rules, that light would be removed if the switch had been properly adjusted, and being a signal Of danger, would mean “ stop ”; so that in order to comply with the rules, and carry red lights by means of which approaching trains, attempting to pass another upon a sidetrack, either from the rear or front, would be signaled, this becomes the most important red light upon the train, for it serves two purposes when a train has turned out to permit another to pass from the front to the rear, first, upon being taken down it is a signal to the employees of the train upon the sidetrack to cover the headlight on the engine of such train; and second, if an employee should negligently, as in this case, cover such headlight without being signaled that the switch was closed, such negligence would no't result in an accident to an approaching ti’ain, for the reason that the engineer of such train would see the cupola light, and bring his train to a stop; and though there may be, in railway usage, a distinction or difference in the use of the words “ meet ” and “ pass,” as applied to a train passing another from the front to the rear, or in the opposite direction, we cannot agree with the contention of counsel, that the rules regarding signals are susceptible of a construction which recognizes that difference. To do so, would be to inject an ambiguity which does not now exist, create confusion where there is now a harmonious *26whole, and make an exception to the rule that red signifies, danger, when no such exception is given, because rule 74, when read in connection with the others and the evidence relating to the manner lights upon a train are displayed, and how they are used as signals, is perfectly clear, and if followed, will’prevent accidents of the kind, which happened to the passenger train in this case, whether such train is attempting to pass one upon a sidetrack, either from the front or rear; and is a prudent provision by which those nearest the point of danger will, by their affirmative act, indicate to the approaching train that all is right; and, while it is true, as contended by counsel for appellant, that the latter part of this rule directs that the headlight of an engine waiting for a train to pass from the front, must be covered as an affirmative signal to the approaching train, we find nothing in this Or other rules which makes the distinction based upon the direction a train is moving which one upon a sidetrack is waiting to let pass, as contended for by counsel for appellant; because nowhere in the rule is the word “ meet ” used, but only the word “pass,” and attaching to the words employed, their ordinary English significance, we find that the rule provides specifically what particular signals shall be given by a train waiting for another to pass, as determined by the direction from which such train will approach, and the evidence clearly justified the jury in finding that, had a red light been displayed from the cupola of the freight train on the night in question, the accident to the engine of the passenger train would not have occurred; because its presence- would have at once warned the engineer of that train of the condition of the switch, and his train being under control, with a distance of not less than between 700 and 800 feet to run, and probably much more, after he passed the engine of the freight, before reaching the open switch, there was no evidence which rendered the result, if the light had been up, at all problematical.
It is contended by appellant that the rules do not provide , for a red light in the cupola of a caboose. Literally this is true; nor do they designate' where any of the red lights on *27the train shall be carried, except on the rear; but they provide for two or more. The cabooses were constructed with the view of carrying a red light in the cupola, and admitting evidence that it was the custom to carry one, so displayed, at night, was but evidence of the fact that the company, in compliance with the rules on the subject, carried this third light in a certain way, and which, in fact, was necessary to be so carried, in order that the rules regarding the giving of signals by means of lights might be fully complied with. For the purpose of displaying this light, a particular kind of lamp was required, and one was specially constructed for this purpose. ■ This was one of the appliances which the company was bound to furnish for use upon its freight trains ; it delegated this duty to the employees using such light; they were required to keep it in good order, and ready for use, and their failure to do so, or ask for or obtain another during the time the regular one was being repaired, was the act of appellant, in so far as other employees might be affected by such neglect; so that the evidence on this subject was ample to warrant the jury in finding that the omission of the employees charged with this duty was the omission of their principal in this respect, and negligence upon its part, in so failing to equip this freight train with that necessary appliance for its safe operation; and under the evidence and the findings of the jury on the two main questions in-'the case, we must answer in the affirmative the very pertinent question propounded by counsel for appellant, in oral argument: Is the presence or absence of a red light in the cupola of a caboose, standing upon a sidetrack, a signal to a meeting or passing train ?
It is claimed that the instruction requested by appellant, to the effect that if there were other lights or lanterns in the caboose, which might have been used in place of the cupola light while it was being repaired, then the defendant cannot be held liable in this action, should have been given. Had there been a lamp in the caboose which could have been used in the place provided for the cupola light, possibly this *28instruction should have been given, but we will not pass upon that question, because there is no evidence upon which to base it; and although there was a red lantern which might have been fastened to the outside of the cupola, there is no rule requiring employees, in the absence of the regular cupola lamp, to do so; and their failure to take this precaution, under such circumstances, will not relieve their principal from responsibility for failure to supply the usual and specific lamp for a particular purpose and place.
Had it not been for the open switch no accident would have occurred to the engine of the passenger train on account of the absence of the red light from the cupola of the caboose; but if the light had been present, the jury found the accident could not have happened, so that the absence of this light was the prime factor in causing the engine to be derailed; and because the employees of the freight were guilty of acts of negligence, which contributed to the accident, the appellant is not relieved from the result of its own, where, as in this case, notwithstanding the negligence of the freight crew, no accident would have occurred had it not been also guilty of negligence upon its part.
The only remaining question to consider is that based upon the exception of appellant to the special interrogatories propounded to the jury, the objection being' that they were so framed and worded as to indicate to them just what answer was required. Special questions submitted to a jury should be carefully drawn, and call- for a direct answer, and although they might be leading if propounded to a witness, that is not an objectionable feature when propounded to a jury, for they are disinterested, and would not be controlled in their answer for the same reason that a witness might, if asked a leading question. Besides, the questions propounded here relate to the very issues upon which the case turned, and called for an answer, either yes or no; and that they were so framed that none other could be given is not objectionable, nor do we think that either of these questions were so worded that they indicated that a certain answer was desired.
*29The case was fairly and intelligently submitted to the jury; the evidence fully sustains the findings on the issues pre-sented, and the judgment of the district court is, therefore, affirmed.
Affirmed.