I've found when reading older literature written by Poe, Tolkien or Dickens that quite often in dialogue and description there will be an exclamation mid-sentence with the sentence continuing afterwards. For example:
Light grew, and lo! the Company passed through another gateway (...) (Lord of the Rings: RotK)
Also common in these books is alas! being mid sentence, with Dickens I recall there being a thank God! as well. Are these kinds of exclamations still used in modern writing or would they be considered archaic?