Complex sentence: Meanwhile, in their first campaign, the companies of Boling and Dill, followed the natives into the mountains, marching in rain, sleet and 3 to 5 foot snow drifts discovering the Ahwahneechees Yosemite Valley refuge on March 27 but found few natives.
Split into simpler sentences: Meanwhile, in their first campaign, the companies of Boling and Dill followed the natives into the mountains, marching in rain, sleet and 3 to 5 foot snow drifts. They discovered the Ahwahneechees Yosemite Valley refuge on March 27 but found few natives.