I myself once performed a demonstration in my physics class where I compared a Helium filled balloon to a Carbon Dioxide filled balloon. Of course, one floats and the other falls to the ground (faster than a balloon filled with room air).

I then showed how my voice sounds higher when I inhale Helium due to the fact that the speed of sound is faster in Helium than in air, and the waves pile up as the slow down at the Helium-Air interface.

To be clever, I asked my students what happens when you breathe in Carbon Dioxide and try the same trick. Your voice should sound far lower. What I didn’t count on was that when you breathe pure Carbon Dioxide, it combines with the water in your lung membranes and forms Carbonic Acid. I almost coughed to death during the demo.

Next time Michelle Bachmann says that CO2 is harmless, have her take a breath out of a CO2 balloon!

Kevin Knuth
Albany NY

I find that I love working in silver. The brilliant white color of the metal is far more beautiful than gold. I really love the Byzantine chain weave, and I feel challenged to make them as small as possible. Here is a picture of my Byzantine weave bracelet handwoven with sterling silver and blue anodized niobium rings. It is only 3/8 of an inch wide.

Blue Byzantine Bracelet made with Sterling Silver and Anodized Niobium

I also love the hexagonal patterns of the Japanese weave. I have been playing with variations that involve different sized rings. I won’t show those here quite yet. But below are two necklaces I have made with this weave.

Japanese Chainmaille Necklace

Springtime Necklace features leaves made from a Japanese-style weave

I am now working on integrating gemstones into the maille to obtain some truly unique designs.

The robot appears to be dragging the victim up the ramp by his/her neck.

Very Nice!

This was #8 in a series of photos from a Boston.com News in Photographs piece.   The caption there reads:

Tokyo Fire Department’s rescue robot transfers a mock victim onto itself during an anti-terrorism exercise in the response to a radiological dispersal device in Tokyo, on November 7, 2008. Tokyo Metropolitan government conducted the exercise with eleven organisations including Metropolitan Police Department. (TOSHIFUMI KITAMURA/AFP/Getty Images)