Although this route would have brought the emigrants to California about 200 miles south of the gold fields, they knew it was too close to winter to attempt a crossing of the central Sierra Nevada over Donner Pass.
Unfortunately for these emigrants, the east–west mountain range shown on the map turned out to be a figment of the map-maker's imagination, and for three weeks the team's westward travel was through barren sagebrush desert with hardly any drinkable water and even less forage for the oxen and horses.
The route they were following began to descend along a dry arroyo that is today known as Furnace Creek Wash, which deposited the teams in the bottom of Death Valley, with the Panamint Range blocking any further progress westward.
Two young men volunteered to make this attempt, William Lewis Manly and John Rogers, and they were provided with enough provisions for about two weeks, and all of the money in the camp - about $30 - with which to buy supplies and animals if such could be found.
Manly and Rogers started southwest, and after two weeks of walking through the Mojave Desert, with little more than a few pounds of dried meat and a makeshift canteen made of gunpowder cans, they stumbled into a settlement, Rancho San Fernando, 30 miles or so northeast of Los Angeles near Tejon Pass.