Camping

Useful links

• How to Use Peppermint Oil as an Insect Repellent. Peppermint oil, while unusually fragrant to humans, acts as a repellent to most insects, especially mosquitoes and fleas. Either use in concentrated form at focal points on clothing or dilute with alcohol and spray. Mix with lemon eucalyptus oil to extend the length of protection to 5 or 6 hours.
• How-to Make Homemade Essential Oil Insect Repellent Spray. Mixture of: 2 oz water, 1.5 oz witch hazel, 50-75 drops of essential oils (like peppermint and lemon eucalyptus).
• Cobalt Blue Glass Bottle 4 Oz with Black Atomizer (3 Pieces) (4 oz per bottle). From Amazon.

Amphitheater

• Mystery of Greek Amphitheater's Amazing Sound Finally Solved. Now, researchers at the Georgia Institute of Technology have discovered that the limestone material of the seats provide a filtering effect, suppressing low frequencies of voices, thus minimizing background crowd noise. Further, the rows of limestone seats reflect high-frequencies back towards the audience, enhancing the effect. The technical paper: Acoustic diffraction effects at the Hellenistic amphitheater of Epidaurus: Seat rows responsible for the marvelous acoustics. Built according to the Pythagorean theory: (YouTube) The Acoustic Harmony of the Epidaurus Theatre (technical). Recreation graphics: (YouTube) The Epidauros Amphitheatre. Examples of the sound from high up in the theater:
  • (YouTube) Acoustics at the Theatre at Epidavros. Single voice.
  • (YouTube) Epidaurus, Greece. Single singer.
  • (YouTube) Epidaurus. Single instrument.
  • (YouTube) Ancient theatre of Epidaurus, Greece 20091020. At end of video tears a piece of paper.