Upon hearing (September 3, 1969) petitioner asserted the defense of deviation from duties, by reason of which deceased was not within the course of his employment when killed. Aside from argument upon weight of the evidence, petitioner's principal contention is predicated upon our decisions in Cochran v. Maassen Tool Supply Co., 204 Okla. 60, 226 P.2d 953; Bayless v. Sparkman Livestock Sales Co., Okla., 350 P.2d 233; Guthrie, Minor, etc. v. Modern Distributors, Inc., Okla., 350 P.2d 488; Dobson, Admx. v. Commercial Oil Transport, Inc., Okla., 371 P.2d 709. Basis of the decision in Cochran was the oft-quoted rule laid down by Cardozo, J. in Marks Dependents v. Gray (N.Y.), 251 N.Y. 90, 167 N.E. 181. Our decision in that case found claimant's own evidence sufficient to support the conclusion that the employer's business was not a concurrent cause for the trip, and the work performed had no part in creating necessity for travel resulting in injury.

"The burden was upon the claimant to establish by competent evidence that at the time of the accident he was on some mission for his employer or doing something for his employer in the course of his employment at the time the accident occurred. Lane-Wells Co. v. Brewer, Okla., 433 P.2d 959; Platner v. Bill Moore Chevrolet, Okla., 400 P.2d 148; Anderson v. Bills Bakeries, Inc., Okla., 393 P.2d 524; Guthrie v. Modern Distributors, Inc., Okla., 350 P.2d 488."

The burden was upon the claimant to establish by competent evidence that at the time of the accident he was on some mission for his employer or doing something for his employer in the course of his employment at the time the accident occurred. Lane-Wells Co. v. Brewer, Okla., 433 P.2d 959; Platner v. Bill Moore Chevrolet, Okla., 400 P.2d 148; Anderson v. Bills Bakeries, Inc., Okla., 393 P.2d 524; Guthrie v. Modern Distributors, Inc., Okla., 350 P.2d 488. Claimant argues that under the provisions of 85 O.S. 1961 § 27[ 85-27], it is to be presumed that in the absence of substantial evidence to the contrary claimant was working in the course of his employment at the time the accident occurred.

The burden is upon the claimant to establish not only that the deceased was on duty at the time of the accident but also that he was on some mission for his employer or doing something for the benefit of his employer at the time the fatal accident occurred. Anderson v. Bills Bakeries, Inc., Okla., 393 P.2d 524; Guthrie v. Modern Distributors, Inc., Okla., 350 P.2d 488. In Dobson v. Commercial Oil Transport, Inc., supra, the deceased was employed by respondent as a safety advisor and his employer furnished him with a car for use in performance of his duties which included supervision of maintenance of vehicles, supervision of drivers and assistance in transportation difficulties. He was subject to call at all times.

The conclusion therein reached was in accord with the statutory presumption, and in no manner supports the argument that the burden shifts to the employer to prove by substantial evidence that the accidental injury did not arise out of and in the course of the employment. An argument identical to that urged herein was advanced in Guthrie v. Modern Distributors, Inc. et al., Okla., 350 P.2d 488, which proceeding involved a stronger factual situation than is presented herein. In the body of the case we said:

The accident occurred on New Mexico Highway 18, which runs entirely within New Mexico north from the place of the accident to within a few miles of the northern boundary of the State. Decedent had not reached a point on this Highway where he might have turned east to reach Dalhart, Texas, as suggested in the examination of witness Mitchell, but this was no proof on any intention of going to Dalhart. Burden of proof to establish that injury was accidental and arose out of and in the course of employment rests upon a Workmen's Compensation claimant. Magnolia Petroleum Co. v. State Industrial Commission, Okla., 361 P.2d 477; Guthrie et al. v. Modern Distributors et al., Okla., 350 P.2d 488. This burden claimant has failed to meet. In Guthrie et al. v. Modern Distributors et al., supra, we said:

¶ 8 The issue of whether an accidental injury arose out of and in the course of employment presents a question of fact to be determined by the State Industrial Court from the proof adduced in the particular proceeding, and its finding thereon will not be disturbed on review when supported by competent testimony. Terry Motor Co. v. Mixon, Okla., 361 P.2d 180; Magnolia Petroleum Co. v. State Industrial Commission, Okla., 361 P.2d 477; Bayless v. Sparkman Livestock Sales, Okla., 350 P.2d 233; Guthrie v. Modern Distributors, Inc., Okla., 350 P.2d 488. The trial tribunal is at liberty to refuse credence to any portion of the testimony deemed unworthy of belief and is not required to accord credence to the greater amount of evidence as against the lesser. ¶ 9 Although claimant maintained that, when injured, he was on a mission for the employer, he did not testify what persons he saw and where he sought to solicit their business.