We found this adorable old puzzle made out of a NUT & BOLT!
This is the actual puzzle - it's so cool!
The trick involves holding it by the threaded end and turning the nut, instead of turning the head (I don't know why it makes a difference but that's the trick.) It is super easy to undo BUT to put it BACK together was hard! So I'm not undoing it again...not even to take a photo to display (sorry.) And it's cute this way so I'm leaving it alone.
So you don't get pinched getting caught without your green
We've got green grounding screws for you!
Do you know what 'green' grounding screws are?
A green chromate finish identifies these screws as grounding screws.
They have Type F threads and a slotted hex-washer head that's formed as one piece to provide a large flat bearing surface. Green grounding screws are used in electrical junction boxes to provide a solid grounding.
New research has found that humans were not the first species to invent the nut and bolt mechanism for screwing one thing to another: weevils do the same to attach their legs to their bodies instead of using the more familiar ball-and-socket joint. ~ from www.PhysOrg.com
This is so amazing that you have to see the photos.
These are weevils.
The article explains that scientist discovered that the top section of weevils' legs are attached to the body via the trochanter, which screws into another small body part called the coxa, which is equivalent to a hip. The inside of the coxa and external surface of the trochanter features threads like those found in nuts and bolts (shocking!)
The muscles turn the legs on the screw threads, an arrangement that allows the weevils to twist their hind and middle legs through 130 degrees, and their front legs through 90 degrees. The joint is more difficult to dislocate than a ball-and-socket joint.
Both parts of the weevil's hip joint fit like screw and nut which increases the mobility of the leg.
* All of the info and photos were taken from the article at www.PhysOrg.com from July of 2011 which we highly recommend.