mitunnelrat
12-26-2014, 01:04 PM
My uncle just showed me this, and I thought it was a pretty cool trick to show, so I found an article on it.
http://www.wikihow.com/Whistle-Using-an-Acorn-Cap
And it can get loud!
http://www.wikihow.com/Whistle-Using-an-Acorn-Cap
And it can get loud!