The largest explosion in Minneapolis' history was the 1878 explosion of the Washburn "A" Mill in downtown Minneapolis. 'Twas heard 10 miles away in St. Paul.

When I was working in a supermarket in the late 1960s, we kids who worked there would amuse ourselves by taking bags of flour, tearing a big hole in them, lobbing them into the incinerator, and then quickly slamming the steel incinerator door shut.

The resulting explosions were powerful enough to bend the half-inch-thick steel door of the incinerator.

So I shudder to think of a flour warehouse with open-flame lighting. That stuff is dangerous.

EDIT: Here's our good friend, Mr. Wizard, explaining how flour dust can be explosive:
https://www.youtube.com/watch?v=8t5iTunRkO4

Are those gas lamps hanging from a pipe?

it looks to me as at least the fire buckets i can see in the image that none have rounded bottoms all fire buckets i have ever seen had rounded bottoms that i believe the purpose being that it forced one to hang it up and thus readily available for use and not have to search for one. another words hang it up or it tips over and loses its contents and it hung up if itd empty it is deemed useless for fire. anyone have different on what i just said and how it might tie into these buckets being flat i believe.

[leading candidate for this years ee cummings commenting fellowship way to go man - dave]

Made with thin fir staves tongue and groove jointed, and with sapling hoops, these were called slack barrels, and they wouldn't hold a liquid for five minutes. They are indeed flour barrels. A crepe-like paper liner inside each barrel prevented sifting the flour out between the stave joints.

Washburn Crosby Co of Minneapolis produced their Gold Medal Flour in Minneapolis, and eventually became General Mills - still producing Gold Medal Flour a century and a half later.

It's weird to see a warehouse look so light, airy, and neat. Today, forklifts allow warehouse-men to lift items to dizzying heights, making sure that the only light available is artificial. And with rare exceptions, nobody would dare put a wood floor in a warehouse--you'd wear right through it, and quickly, with the tires of your forklifts.

That noted, the frame of the building looks about the same as today. The big difference is you'll get a lot more lights hung from it, and instead of rivets, they're often welded.

I'm no historian of architectural engineering, but the construction of this warehouse must have been state of the art for 1900.

Gold Medal - flour, still today.
I wonder what's in the barrels.

With that many sacks of flour stacked that deep, I hope they have a couple of hungry cats hanging around.

Still a brand today, but, pretty sure, this isn't how it's stacked these days!

Gold Medal Flour was my mother-in-law's favorite brand. My wife still uses it today.

If you take away the barrels, the sacks, the hanging lamps, and the buckets of sand, this warehouse looks uncannily modern. Something about the crisp, even brightness and the light, metal structure.

Can't imagine how many man-hours went into stacking just the sacks on the left, not to mention the thousands of barrels!! I believe I see a couple of them whose efforts helped make this scene so compelling over a century later.

A sand-filled bucket 10 feet off the floor on every column for fire control.