I think I remember that on the question whether the court of one district could have an attachment executed in another to compel the attendance of a witness, you satisfied us it could not. will you have the goodness to give me a formal opinion on that question with as little delay as convenient? I presume it could no more enforce the giving a deposition. an existing case may render necessary a reliance on this point of law. I salute you with sincere affection & respect—