Section 6.--And be it further enacted, that the said several superintendents of posts shall, ex-officia, be Superintendents of Indian Affairs west of the Indian Territory, Neocho, subordinate to and under the full control of the Commissioner-General of Indian affairs at Washington. That they shall by virtue of their offices, be conservators of the peace, with full powers to the extent hereinafter prescribed, in all cases of crimes and misdemeanors, whether committed by citizens of the United States or by Indians within the frontier line aforesaid. That they shall have power to administer oaths, to be valid in the several courts of the United States, to perpetuate testimony to be used in said courts, to take acknowledgments of deeds and other specialties in writing, to take probate of wills and the testaments executed upon the said frontier, of which the testators shall have died in transit between the State of Missouri and the Territory of Oregon, and to do and certify all notarial acts, and to perform the ceremony of marriage, with as legal effect as if the said several acts above enumerated had been performed by the magistrates of any of the States having power to perform the service. That they shall have power to arrest and remove from the line aforesaid all disorderly white persons, and all persons exciting the Indians to hostilities, and to surrender up all fugitives from justice upon the requisition of the Governor of any of the States; that they shall have power to demand of the several tribes within the said frontier line, the surrender of any Indian or Indians committing acts in contradiction of the laws of the United States, and in case of such surrender, to inflict punishment thereon according to the tenor and effect of said laws, without further trial, presuming such offending Indian or Indians to have received the trial and condemnation of the tribe to which he or they may belong; to intercept and seize all articles of contraband trade, whether introduced into their jurisdiction in violation of the acts imposing duties on imports, or of the acts to regulate trade and intercourse with the several Indian tribes, to transmit the same to the Marshal of the Western District of Missouri, together with the proofs necessary for the confiscation thereof, and in every such case the Superintendent shall be entitled to receive one-half the sale value of the said confiscated articles, and the other half be disposed of as in like cases arising under the existing revenue laws. Section 7.--And be it further enacted, that the several Superintendents shall have and keep at their several Posts, seals of office for the legal authentication of their public acts herein enumerated, and that the said seals shall have as a device the spread-eagle, with the words, "U. S. Superintendency of the Frontier," engraved thereon.