delivered the opinion of the court.

(After stating the facts as above). The principal complaint of appellants is that the court below refused to grant them a peremptory instruction.

The ground upon which this instruction was sought is that appellee was not injured by reason of their or their servants ’ negligence but by the negligence of a servant of .King & Clark, independent contractors, over whose servants appellants had no control.

“An ‘independent contractor’ is one who renders service in the course of an occupation, representing the will ■of his employer only as to the result of his work, and not •as to the means by which it is accomplished.” 4 Words and Phrases, 3542.

“Where one person is employed to do certain work for another who, under the express or implied terms of the agreement between them, is to have the right of exercising control over the performance of the work, to the ■extent of prescribing the manner in which it shall be exi•ecuted, the employer is a master, and the person employed is his servant.” 1 Labatt’s Master and Servant, '9. . •

Tested by these definitions, it seems clear that, in so far as the Callahan Construction Company is concerned, King & Clark were independent contractors, and that no verdict should have been rendered against it.

The servant of a contractor may be, under some circumstances, the servant also of the principal employer, .and .such is the case (1 Labatt’s Master and Servant, 123) when, “That by virtue of the original agreement between the principal employer and the contractor the former acquired the right of giving directions to the servants of the latter with regard to the.manner in which the work was to be done. Manifestly, under such circumstances, the contractor is not, in the proper sense of the term, an ‘independent contractor,’ and, according to the •decided preponderance of authority, both he and such *118persons as lie may engage for the work in hand are in-law the servants of the principal employer for all purposes.” "When, in addition to the right to direct the-manner in which work is to be done by the servants of a contractor, the principal employer reserves the right to require the contractor to discharge such of his (the contractor’s) servants as are not satisfactory to him (the-principal employer), then there can be no doubt that the servants of the contractor are servants of the principal employer. This is the exact situation here in so far as the running of trains by the servants of Callahan & Company and of their contractors, King & Clark, over the road of appellant Louisville & Nashville Railroad Company is concerned. It is true that the contract between this company and Callahan & Company, the obligation of which in this respect was assumed by King & Clark, does not in express terms confer upon it the right to control the servants of Callahan & 'Company while engaged in.the running of trains upon its road, but “a provision in. an agreement which confers upon the superior employer the right of controlling the contractor himself in respect to the details of the work must necessarily imply that he-is to retain the right of controlling, to the same extent, the servants who are the instruments through whom the contractor performs the work. Otherwise such a provision would be meaningless and ineffectual.” 1 Labatt’s. Master & Servant, 126.

It follows from the foregoing views that the court below erred in permitting a verdict to be rendered against Callahan & Company, but committed no error in that regard in so far as appellant Louisville & Nashville Railroad Company is concerned.

The verdict rendered was in the following language: “We,'the jury, find for the plaintiff and assess his damages at five hundred dollars.” One of the contentions of appellants is that this verdict'should be set aside for the reason that it is “too indefinite. It was for the plaintiff, *119but did not specify whether it was against one or both of the defendants. ’ ’ There is no merit in this contention.

The judgment of the court below, in so far as it affects the Callahan Construction Company, will be reversed,, and the cause to that extent dismissed,- but, in so far' as it affects the Louisville & Nashville Eailroad Company, the judgment of the court below is affirmed.

Reversed..

Affirmed..