Before developers saw to cut and cut the flour mills inside Pillsbury, they stood at the ready beside various purposeful chutes the traversed the floors of between sorters. These machines were belt-driven by the power of Pillsbury’s Mississippi headraces and turbines, the force of which notoriously shook the building’s foundations themselves. The wheels would change the grade of the flour, or the size of the dust produced from crushing the kernels.
Chutes from a hundred machines interconnect to more machines and chutes on a dozen factory floors.
Like a railgun pointed at the Rockies… the boom would direct tailings–junk rock–outside of the dredge pond.
A broken-down wooden grain chute.
With the maintenance door open you can see the buckets on in the vertical conveyor.
A closeup of the now-scrapped steel chute.
On first impression it might look like a funky mailbox, but trust me on this one; it’s a flour bolter chute. In flour milling, “bolting” means sifting the flour through successively smaller screens.
Judging from old pictures and maps, raw ore was dumped through these hatches, stamped into a rough powder, and hastily sorted before sending the best ore to the mill. Mills charged by tons of rock sent to them, so it did not pay to send them obvious tails.