Complex sentence: Carrington sent his most cautious officer, Captain Powell, out of the fort to relieve the wood train with a cavalry company and mounted infantry and explicit orders not to pursue the Indians beyond Lodge Trail Ridge, two miles north of Fort Kearny.
Split into simpler sentences: Carrington sent his most cautious officer, Captain Powell, out of the fort to relieve the wood train with a cavalry company and mounted infantry. He gave explicit orders not to pursue the Indians beyond Lodge Trail Ridge, two miles north of Fort Kearny.