cited and discussed by Professor Bohlen in 25 Harvard Law Review, 401, et seq. From his discussion and the cases referred to by him, and from the later decisions of the English courts, the rule has been established, as we consider in accordance with sound reason, that the employer’s liability in such cases depends upon whether the conveyance has been provided by him, after the real beginning of the employment, in compliance with one of the implied or express terms of the contract of employment, for the mere use of the employees, and is one which the employees are required, or as a matter of right are permitted, to use by virtue of that contract. See Davies v. Rhymney Iron Co. 16 T. L. R. 329; Holmes v. Great Northern Railway, [1900] 2 Q. B. 409; Whitbread v. Arnold, 99 L. T. 103; Cremins v. Guest, Keen & Nettlefolds, [1908] 1 K. B. 469; Gane v. Norton Hill Colliery Co. [1909] 2 K. B. 539; Hoskins v. J. Lancaster, 3 B. W. C. C. 476; Parker v. Pout, 105 L. T. 493; Walters v. Staveley Coal & Iron Co. 105 L. T. 119, and 4 B. W. C. C. 89 and 303; Greene v. Shaw, [1912] 2 Ir. 430, and 5 B. W. C. C. 530; Mole v. Wadworth, 6 B. W. C. C. 128; Edwards v. Wingham Agricultural Implements Co. [1913] 3 K. B. 596, and 6 B. W. C. C. 511; Walton v. Tredegar Iron & Coal Co. 6 B. W. C. C. 592.
The, finding of the Industrial Accident Board that Donovan’s transportation was “incidental to his employment” fairly means, in the connection in which it was used, that it was one of the incidents of his employment, that it was an accessory, collateral or subsidiary part of his contract of employment, something added to the principal part of that contract as a minor, but none the less a real feature or detail of the contract. Whatever has been uniformly done in the execution of such a contract by both of the parties to it well may be regarded as having been adopted by them as one of its terms. Especially is this so where none of the provisions of the contract has been shown by either party, but everything is left to be inferred from their conduct. That was the reasoning of this court in such cases as Gillshannon v. Stony Brook Railroad, 10 Cush. 228, 231; McGuirk v. Shattuck, 160 Mass. 45, 47; Boyle v. Columbian Fire Proofing Co. 182 Mass. 93, 98; Kilduff v. Boston Elevated Railway, 195 Mass. 307; and Feneff v. Boston & Maine Railroad, 196 Mass. 575, 577.
Accordingly we are of opinion that the Industrial Accident