IndustryQuincy Smelting Works

The Combo Furnace (p1)

When the Quincy Smelter was first built, its compliment of four reverberatory furnaces was more than adequate in meeting the company’s needs. Over the ensuing years, however, the smelter’s capacities would become strained as the complex began handling an increased workload from not only the Quincy Mine itself, but also a dozen or so independent mines that were also using the smelter for its own copper. In response the company was forced to erect a new furnace along with a new building to house it. Built just to the east of the old furnace building, this new furnace was known as the No. 5.

The No.5 furnace would go through several changes during the course of the smelter’s life, evolving to meet the constantly changing needs of the complex. In 1910 the furnace was rebuilt, this time on the building’s northern end. During this change the No.5 building was joined to the old furnace building and the two became one. In 1919 the furnace would be rebuilt yet again, but this time it would be joined with a similarly rebuilt No.3 furnace next door to create a combined “mega” furnace capable of refining over 130 thousand pounds of copper in a single charge.

This new combo furnace divided up the work of smelting between the two furnaces, allowing for essentially two charges to be smelted at the same time. In this configuration the first furnace (the No.3) would perform the first half of the smelting process – the melting and skimming of the copper – while the new No. 5 would perform the second half – the rabbling and poling of the copper. The two furnaces were connected with a launder which allowed molten copper from the first furnace to be transferred into the second. This way the first furnace could be at work on another charge while the second furnace was finishing up the first.

This new configuration required a major refit of both the old furnace building and the new No.5 building as well. The most telling of these changes was the addition of a third story to the old furnace building (a renovation we covered in the post about the exterior of the furnace building) as well as the addition of a new casting plant on the east side of the No.5 building. In the photo above – taken in the 1970s – you can clearly see these changes in the roof line of the structures.

It is these alterations that are responsible for the current configuration of the furnace building’s interior as we encountered it on our tour. The only old-school furnace still standing in the furnace building today is the one we featured last week, tucked into the south-west corner of the structure. The remaining three furnaces had all been removed at some point in the smelter’s history, replaced by the new No.3 which now takes up a sizable portion of the furnace building’s north-east corner. Its that furnace that we set our sights on next.

Unfortunately there isn’t a whole lot of the No.3 furnace to see, at least without putting yourself at some risk. Due to the incorporation of several automatic loading systems the entire furnace is surrounded by a spiderweb of steel girders and platforms. Only a small portion of the furnace’s brick work can be seen here on the left side of the photo. Up to the right can also be glimpsed its chimney, which sits atop a steel platform of its own. To get a better idea of what exactly this furnace looked like we have to take a look at its original plans…

Here’s a side view of the furnace in question, as seen from the neighboring No.5 furnace. The furnace’s hearth sits in the center of the photo, topped by two large charging doors through which the copper would have been loaded. The firebox stands to the right, loaded from an overhead coal bin. The coal bin itself was loaded by means of an overhead trestle, which was also used dump mineral into the furnace’s loading doors.

Peering up into the grid work of steel and iron I can make out the base of the No.3’s chimney, a rather large and robust brick monstrosity at that.

And here’s the top of that stack, as it currently stands protruding up out of the furnace building’s roof. From here it would have been topped by a length of steel stack as well. That steel stack is no longer standing however.

Or is it? Sitting next to the bast of the No.3 stack is this item – which appears to be a steel stack. But its odd angle seems to suggest its just sitting there, and a closer look at its base doesn’t seem to suggest its actually connected to anything – furnace or otherwise. I wonder if this is that upper portion of steel stack that was once attached to the top of the No. 3’s brick chimney?

Before heading off to the neighboring No.5 furnace, we took a wide look around at the neighboring space around the No.3 furnace. Here the building soars up into the rafters, in a large open area taken up primarily by an overhead crane system. (the crane sits just off to the right in this photo). The crane was used to charge the furnace as well as assist in any repair and maintenance it may need. Also seen in this photo is second-floor trestle (top left) used to transport slag / coal to and from the furnace.

With our exploration of the old furnace building and No.3 furnace now complete, we turned our attention next door to the other half of the combo furnace – the No.5.

To learn more about the No.3 furnace and its history be sure to visit the Quincy Smelter Blog for their own virtual tour.

Don’t forget if you have any photos of your own of the smelter or wish to contribute your own exploration stories, make sure to post them over at the Copper Country forum’s Quincy Smelter Thread!

Show More


  1. That building can be such a nightmare for photography (lighting and safety reduce what you can do) but you managed to get some good shots.

    Enjoying it all.

  2. Great image of the connection between No.3 and No.5. I’ve also never managed to notice that stack section just sitting there. Btw, the brick furnace base is so robust because it’s actually a 300 h.p. Cook waste heat boiler (you’ll note that the original elevation lists it as the “No.3 melter and boiler”). They used it to generate power with the waste gases from the furnace below.

  3. Thanks Craig for the info! I thought the thing looked odd, and I knew it noted “boiler” in the elevations but I couldn’t figure out where the heck that boiler was. So I just ignored it in the hopes it would go away.

    Also, I forgot to link back to the Quincy Smelter Blog when I first put this post up. So for those of you who missed it, make sure to head on over to the Quincy Smelter Blog to learn more about the No.3 furnace (including about the boiler which I didn’t mention!)

    And SMG, thanks for the compliments. It was a tough shoot in there, but I’ve been to worse. But I’m not exactly going to win any photography awards either. . But for more professional types like dcclark I’m sure it was a fun challenge to say the least!

  4. wow, i had never noticed that overhead crane before. what a weird setup; definitely unique from any other ive seen…im used to the kind who run along a track and support system that is shared with the structure of the building itself, as in auto plants, or steel mills, etc

Leave a Reply

Your email address will not be published. Required fields are marked *