I clambered out upon the sill, but I hesitated to jump until I should have heard what passed between my savior and the ruffian who pursued me. If she were ill-used, then at any risks I was determined to go back to her assistance. [. . .]
Doyle, Arthur Conan [. . .]
Could you please explain why subjunctive “were” is used here? I don’t think it indicates something counterfactual.
It is an interesting specimen. Please keep in mind that it was written quite some time ago. I understand this conditional as a Type 2, but from the perspective of the past. That is, the speaker is inviting us into his past thoughts.
It is as though the speaker is saying that he thought at the time that he would go back to her assistance if she were ill-used: "If she were ill-used, I would go back to her assistance." He conceives of her being ill-used by his pursuer as unlikely.
Compare: "I thought at the time, 'If she should be ill-used, I would go back.'"