She hadn't thought about his feelings or motive to help.
There was a practical motive for using this weapon.
She wanted to find, and still seeks, some secret motive in our actions.
In particular that conception which regarded "ambition" as the guiding motive in his career has been dispelled by a more intimate and accurate knowledge of his life; this shows him to have been very little the creator of his own career, which was largely the result of circumstances outside his control, the influence of past events and of the actions of others, the pressure of the national will, the natural superiority of his own genius.
Steam is an extremely useful motive power for all cranes that are not worked off a central power station.