Sam L. Mitchill has, tho perhaps indiscreetly, ventured to entertain a Sentiment that the speedy cessation of his Senatorial functions might coincide with the President’s wish to find a man that would answer to represent this country in a diplomatic capacity at St. Petersburgh. He therefore ventures to suggest the hint, not obtrusively, but with the intention of signifying his willingness to act, if thought worthy of employment on this occasion.