Roars

I'm almost finished with Mary Roach's excellent book Spook. It's exactly the kind of book that the psuedo-scientific religious find extremely unconfortable because it comes up with rational pedestrian explainations for things which many report to be evidence of the supernatural. It's done in a non-condecending, humorous tone and Mary, like me and many others, want to believe in some of this stuff but can't find any reason to.

Part of Spook focuses on ghosts and hauntings and, at least so far, is one of the best parts of the book. Disclaimer: When I was young, until about the age of 11 or 12, I saw ghosts from time to time. I vividly remember them when I was 5 or 6 and would still hear things/feel things at night into my teen years. Mary goes through this pretty throughly and does a great job talking about how humans precieve infrasound and how we react. Infrasound is the term for an acoustic (longitudinal) wave with a frequency between 10 and 20 hertz, just below the threshold for hearing. You still precieve sounds this low, you just don't hear them. What do you do? Well, you panic a little.
It turns out that a lot of animals communicate by infrasound, especially ones with large territories to defend. The beauty of low frequency waves is that they travel for fucking ever, so if your an elephant or a rhino or a whale, infrasound is a good investment for you.

Or, if you're a tiger.

It turns out tigers communiate a lot through infrasound and humans (or at least soem humans who have not yet ruined their ears by playing the Yes Album at 120db for 18 hours a day) respond rather strongly to this.

It also turns out that your PC speakers can do a pretty good approximation of sounds in this range.

So, I went to a site Mary suggested here, read through and scrolled down to the first speaker. I hit the button, fully prepared to hear a tiger roar. And I did. What I was not prepared for, so much so that I burst out laughing afterwards at my foolishness, was the little spike of pure fear that came with it. I litterally got goosebumps. I played it a few more times and realized that part of what I felt was the little dark feeling of something in the room I had when I was a kid. Add to that the dark, too much imagination and some religion classes and I am fully satisfied I understand the creepiness feeling.

Now I want to do two things: 1) I want to watch Ghost Hunters again on Sci-Fi. I watched a few times hoping they would find something, but they never seemed to come up with anything convincing. I want to see if they are in environments which are likely to be good ultrasound resonators. and 2)


I want to play these sounds for the cats...