“ They are plainly within its spirit, and, in our opinion, fairly within its words, 'any tribe of Indians.' Although sedentary, industrious, and disposed to peace, they are Indians in race, customs, and domestic government, always have lived in isolated communities, and are a simple, uninformed people, ill-prepared to cope with the intelligence and greed of other races. It therefore is difficult to believe that Congress in 1851 was not intending to protect them, but only the nomadic and savage Indians then living in New Mexico. ”