> There used to be flash cubes called "Magicubes". I
> don't know why they worked, but they didn't require electricity! You
> could buy one, take it out of the wrapper, push a pencil, drinking
> straw (flattened) or anything else into one of the holes in the base,
> and "WHOOSH!" you see a spot in front of your eyes for hours.
>

A spring wire would be released by a lever on the camera that pushed up through that hole, just like you did with the pencil. The wire would strike the base of the flashbulb, which contained small piezo crystals. The shock would cause them to emit a high-voltage spark which ignited the primer and the metal foil in the oxygen-filled tube. 11 years ago I sold MagiCubes for about $3.50 for 3 cubes (12 flashes). GE and Sylvania were the two big names in flash bulbs, and they mostly departed the business since then.

> They are a cube about 7/8 inch square, they used to work with
> the old Kodak Instamatic and 110 Instamatic cameras. Four flashes
> (bulbs) per cube.

> You can buy a strobe for an old 35mm SLR at a garage sale or
> thrift store (flea market) for really cheap. Once you figure out which
> leads on the mounting base to short out (some even had remote trigger
> cords) you are all set for as much night blindness as you can stand.
> Why bother buying a strobe when you can get them for free? The disposable cameras that have built-in flash units can frequently be picked up at one-hour labs for no cost. Just ask the people who run the labs to save you a few of these things.

Caution. These things typically work at 300 volts and store a good sized charge in their capacitors. If you are not sure about proper precautions with this kind of equipment, don't play with it.

For that matter, I wouldn't play with an electronic flash in ANY wet area. If your hands are wet with salt water when you trigger one of these things you can give yourself a severe shock. I had that happen once and I do not want to repeat the pain, thank you.

Cattle prods, and defibrillators--like you see in the Emergency Room on ER, use the same process.

So, if your electronic flash zaps you while you are trying to get the attrention of someone, I think it is best to have a flare on board to signal that you are in distress.

Ever think of signalling with LEDs? How about a $10 double AA maglite flashlight? It is sealed with `o` rings and works on nice, safe, LOW voltage.

Paul Jacobson