Sir, I received this morning the enclosed communication from U.S. Attorney General of this Territory. My friend, the Attorney General is quite sick, but will so soon as he recovers, institute proceedings against certain white men in the Southern part of the Territory, who, it is believed, and indeed, I know, are the guilty parties in the perpetration of the unparalleled massacre. By diligent inquiry during the last eight months, and while on my late visit south, and since, I have gathered many important facts in relation to the terrible massacre in September, 1857: more perhaps than any one else. I will, in a very few days (by next mail,) furnish you with a full statement of all the material facts concerning the massacre in question. I hope to get the children started to-morrow, when I will expect a short breathing time again. The two boys, which are retained, and in my possession, are I judge, about eight or nine years old, and both remarkably intellectual and, in my opinion, competent witnesses. I am unable to say when the court will be held in the Southern portion of the Territory.