It has been a year since I recorded some unusual sounds at what I call the Troll Bridge. This bridge is located in rural Greene County, Illinois.
Painting (1915) by John Bauer -  Wikimedia Commons
To familiarize yourself with the incident it would be best to read the three posts from last year.
Troll Under The Bridge, Pt. 1Â
Thoughts on ‎â€Troll Under The Bridgeâ€
The discussion has centered around whether the sound that was recorded:
1. Is the sound bipedal or quadrapedal?
2. Is the sound that of a dog, a horse or unknown?
It must be remembered that I was unable to record either a dog or a man running across the bridge in that neither was heavy enough. I weigh 240 lbs and the recorder did not pick up any sounds at all as I ran back and forth the bridge. It is assumed that whatever was running across the bridge was very heavy. I was unable to find anyone living close to the bridge that raised horses. Therefore, I was unable to record a horse galloping across the bridge. However I found a couple of horse sound samples on the net.
Although I can not the answer the question as to the source of the recording  I can provide several other recordings for comparison, (Copyrighted horse sound clips courtesy of  Soundrangers.com)
1. The original recording of 24 Nov 2010. The Troll Under The Bridge
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Clip # 2 – The original file (shortened to 13 seconds) showing just the running sounds.
Click here to listen to sound clip: Â Â The Bridge Runner – 24th of November 2010
Waveform and Spectral View
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Clip # 2 – A recording of my dog Belle running up the wooden stairs between the deck and patio of our home.
Click here to listen to sound clip: Â Â Belle_Running_Up_Stairs
Waveform and Spectral View
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Clip # 3 - A recording of  a horse galloping on dirt.
Click here to listen to sound clip: Â Â Horse Galloping on Dirt # 1
Copyrighted sound clip courtesy of  Soundrangers.com
Waveform and Spectral View
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Clip # 4 - A second recording of  a horse galloping on dirt.
Click here to listen to sound clip: Â Â Horse Galloping on Dirt # 2
Copyrighted sound clip courtesy of  Soundrangers.comÂ
Waveform and Spectral View
It is my opinion that it sounds like a horse. The average horse weighs around 1000 pounds, it either has hooves or metal shoes, and the amount of weight distributed by area on each hoof would be more than a man, dog, or Sasquatch. You can hear horses galloping on sand here:
http://www.youtube.com/watch?v=23YD_wRVGDo
In my opinion a Sasquatch, especially in all four mode, would be quieter due to the size and padding on the hands and feet. I think it would exert less weight per square inch than a horse, and thus be much more muted.
I really don't think it sounds like a horse (lifelong rider here). A galloping or cantering horse makes a distinctive ba-da-BUMP ba-da-BUMP sound, as the gallop is a three-phase gait. After the stressed "bump", a horse is briefly airborne while it brings its legs up and forward again during the suspension phase. Whatever is running through the bridge makes a thump-thump thump-thump, and the sound is more muffled/padded than hooves on wood would be.
Another factor: you said this was recorded at night, I believe. Horses, like humans, rely a great deal on their eyesight, and are easily spooked by enclosed or dark spaces, as anyone who has tried to get a jittery horse into a trailer can attest. There is no way in the world, IMO, that a loose horse galloping around at night would unerringly aim itself into the darkness of a covered bridge unless it knew the bridge very well, was being pursued, or was desperate to get to whatever was on the other side as quickly as possible. A horse under saddle could probably be aimed into the bridge but it would, again IMO, be quite dangerous for a rider to do that at night, assuming the bridge is tall enough to safely accommodate a horse and rider. Finally, I don't hear it snorting or breathing the way a horse would, either… 🙂