Usefully

adv. [f. prec. + -LY².] In a useful manner; so as to be of use; to a useful end; beneficially, profitably, serviceably.

1634.  Massinger, Very Woman, III. ii. Serve usefully, Serve all with diligence.

1656.  Cowley, Davideis, III. 281. How the kind Sun usefully comes and goes.

1711.  Steele, Spect., No. 145, ¶ 2. You cannot employ yourself more usefully.

1781.  Gibbon, Decl. & F., xxx. III. 175. Whose arms would have been more usefully employed to maintain the Roman limits.

1807.  G. Chalmers, Caledonia, I. III. v. § 3. 357. The notices of topography come in here, usefully, to illustrate the obscurity of history.

1868.  Kinglake, Crimea, III. 144. It was hardly one which could be usefully submitted to a numerous assembly.