In the last of these letters, Mr. Lincoln refers to his "duel with Shields." That was another of the disagreeable consequences which flowed from his fatal entanglement with Mary. Not content with managing a timid, although half-frantic and refractory, lover, her restless spirit led her into new fields of adventure. Her pen was too keen to be idle in the political controversies of the time. As a satirical writer, she had no rival of either sex at Springfield, and few, we venture to say, anywhere else. But that is a dangerous talent: the temptations to use it unfairly are numerous and strong; it inflicts so much pain, and almost necessarily so much injustice, upon those against whom it is directed, that its possessor rarely, if ever, escapes from a controversy without suffering from the desperation it provokes. Mary Todd was not disposed to let her genius rust for want of use; and, finding no other victim handy, she turned her attention to James Shields, "Auditor." She had a friend, one Miss Jayne, afterwards Mrs. Trumbull, who helped to keep her literary secrets, and assisted as much as she could in worrying the choleric Irishman. Mr. Francis, the editor, knew very well that Shields was "a fighting-man;" but the "pieces" sent him by the wicked ladies were so uncommonly rich in point and humor, that he yielded to a natural inclination, and printed them, one and all. Below we give a few specimens:-- LETTER FROM THE LOST TOWNSHIPS. Lost Townships, Aug. 27, 1842. Dear Mr. Printer,--I see you printed that long letter I sent you a spell ago: I'm quite encouraged by it, and can't keep from writing again. I think the printing of my letters will be a good thing all round,--it will give me the benefit of being known by the world, and give the world the advantage of knowing what's going on in the Lost Townships, and give your paper respectability besides. So here comes another. Yesterday afternoon I hurried through cleaning up the dinner-dishes, and stepped over to Neighbor S----, to see if his wife Peggy was as well as mought be expected, and hear what they called the baby. Well, when I got there, and just turned round the corner of his log-cabin, there he was setting on the doorstep reading a newspaper. "How are you, Jeff?" says I. He sorter started when he heard me, for he hadn't seen me before. "Why," says he, "I'm mad as the devil, Aunt'Becca!" "What about?" says I: "ain't its hair the right color? None of that nonsense, Jeff: there ain't an honester woman in the Lost Townships than"-- "Than who?" says he: "what the mischief are you about?"