The Rockwell hardness tester to measure the hardness of metal measures resistance to penetration like the Brinell test, but in the Rockwell case, the depth of the impression is measured rather than the diametric area. With the Rockwell tester, the hardness is indicated directly on the scale attached to the machine.
(Redirected from Apache Nation) The Apache (/ÉËpÃ¦tÊiË/; French: [a.paÊ]) are culturally related Native American tribes from the Southwestern United States, and have traditionally lived in Eastern Arizona, Northern Mexico (Sonora and Chihuahua), New Mexico, West Texas, and Southern Colorado.
It has been said that they were one of the first tribes to learn how to ride and use horses. By 1700, a large portion of the Apache Indians had migrated to the Kansas plains. They were not accustomed to living and farming on the plains, but made due with some crops such as watermelon, beans, and corn. Eventually, their weakness was overtaken by the Comanche tribe.