He has but one fault, he is somewhat wilful; but really, on referring for the moment to what he said, do you truly believe that Mithridates used these precautions, and that these precautions were efficacious?
"Alas!" exclaimed Mercedes, "if it were so, if I possessed free-will, but without the power to render that will efficacious, it would drive me to despair."
There are no more uses of "efficacious" in the book.
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The drug is safe and efficacious.
He would weep for hours together, and I verily believe that to the very end this spoiled child of life thought his weak tears in some way efficacious.