Princeton Swing Bridge, looking southwest
The navigation channel was on the far side of the swing pier.
Photo taken by Robert Thompson in December 2010
BH Photo #191543
Swing bridge truss configurations can be difficult to neatly classify due to the unusual way that forces work in them. However, this bridge is mostly a Warren rather than a Pratt.
The builders plate on the bridge is somewhat misleading. The bridge was built in 1901 when the rail line was extended from Princeton to Marshfield. Early photos show the approach span on the south side supported on wooden legs or piles. That apparently did not work too well and it was replaced by a new approach built on concrete piers. The builders plate is on the new approach and if I recall correctly the date on it is 1909. I do not know of a builders plate on the swing span.
I have not found a name of the actual bridge design, only that it seems to be a combination of Pratt and Warren designs.
Good catch, Jeff! You found the Builder's Plaque; I was in a rush when I documented it, and I didn't think to look closely at the plain rolled I-beam approach spans.
Nice pictures, too.
I was doing a topographic survey along this old RR bed a few years ago and came across this gem. Beautiful winter pictures! I have attached a few I took at the time I surveyed this bridge included the builders plaque, which was located on the west side of the fixed span, south of the main span. According to the builder's plaque it was built by the American Bridge Company of New York, 1908.
I spent a couple of years trying to find this little gem. I only had a vague idea of where it was located; all I had to work from was one old photograph with no caption. Google Earth is a wonderful tool!
When I was in middle and high school back in the 1980s, this bridge was where we had to run to from the school during track practice. The CNW had just pulled up the rails a couple of years earlier and the city had just built its new sewer plant which used the right of way for an easement for their discharge pipe into the Fox River so clear unobstructed views of the entire structure were easy to get from County Highway D.
I can remember my first time crossing this bridge one tie at a time for fear of falling in the river since it had no railings and I knew I would certainly smash my head on a girder on the way down. The fear soon went away though and we would ride across the bare ties with our bikes being very sure to hold those handlebars stiff so the front wheel didn't slip sideways and fall between the ties.
Eventually, I believe it was the snowmobile club that first got the railings installed since the CNW sold almost the entire right of way back to the landowners rather than the state or the county for a trail. It did however become a major snowmobile route. I still think to this day that the people of Green Lake and Waushara County deeply regret their shortsightedness in refusing to make the entire route a bikepath.
It appears a very significant historical piece has been removed from the deck. I distinctly remember in the middle of the deck directly over the center pier was a low profile capstan that stuck up between the ties but would have been below the height of the railhead. When we climbed down under the deck we could see that this capstan was geared to the huge fixed bull gear attached to the center pier. At the time, as 11 and 12 year olds, we believed that they must have had some kind of small engine that a bridge tender would drive onto the bridge and connect to the capstan. Afterall, how else would you move such a massive bridge? Of course, now 30 years later we have realized thaat the railroad probably just hurried one or two strong guys which capstan poles, since the gear ratio would have probably made it possible to manually operate.
It nice to see that the bridge is still there and able to be documented. I still remember the year they demolished the old Hwy 23 drawbridge. We kids all knew how much it shook when the bean and corn trucks rolled over it. The new bridge was wider and solid, however I doubt anyone bothered to document the history that was lost when the navigation channel was permanently shut by another concrete slab bridge.