According to Stella H. Day in her book "Builders of Early Millard", and Harriet's diary, Isaac and Hattie owned a livery stable and operated a stage line between Salt Lake City and Bingham. This was in the early 1870’s, when they first moved to Alpine County and then on to Millard County, where daughters Maudie (1871) and Stella (1877) were born (registered at county seat Fillmore).
I have been able to verify that Isaac did run a daily return stage line between Salt lake City and Bingham. The 1873 Salt Lake City Directory, Hannahs & Co, contains the following timetable:
Arrivals and Departures at Wells Fargo & Co’s Office
DEPARTURES For Bingham – via Gandy & Pierce’s stages, at 7. A.M.
From Bingham, daily at 5:30 P.M.
How long the 22 mile journey took depended on the weather and gradient.
Bingham has only one street, squeezed into a mountain gulch, 6 miles (9.7 km) long.
In E.L. Sloan's directory for 1874 Bingham is described as follows:
"The business centre of the West Mountain mining district, is located in Bingham Canon, and is the present terminus of the Bingham Canon and Camp Floyd R.R. Its people are enterprising, and surrounded as it is by immense deposits of silver-bearing lead ores and by gold diggings, there is undoubtedly a prosperous and permanent future before it. Below the town, lower down the Canon, is the smelting works of the Winamuck Company."
Read more about Bingham Canyon and its history here.
Isaac’s stagecoach line is not mentioned in the 1874 Directory, possibly due to the completion of the railway line between Salt Lake City and Bingham Canyon mentioned above. Wells Fargo and Co. did however have an agent in Bingham, L.H.Washburn.
Bingham Canyon is a canyon of the Oquirrh Mountains with an elevation of 6 400 feet (1 951 m), 22 miles (35 km) south west of Salt Lake City. Originally (1848) it was a farm pioneered by Mormons Thomas and Sanford Bingham. In the 1860's it became a booming mining town, dealing in gold then silver and lead and, in the 20th centrury, copper. The world's largest open-pit mine, Kennecott Coirp. Bingham Mine is located in nearby Upper Bingham.