What is the safest pistol on the legal market?

First let me say thank you to the people who say guns can be dangerous. I agree. If you want to make a heart felt comment please put it on a bumper sticker. What I mean is a real gun on a scale from one to ten. One being a gun made of transparent material so that the user can see the bullet go inside of the chamber and has a trigger that takes a weight lifter to pull . Ten being an all camouflaged- touch the handle with you're pinky and it shoots eleven times- gun. The safest that I know of would be an antique revolver. You can't see if anything is in the chamber but at least you can see where the rest of the bullets are. On the safety scale does anything compare with great grandpa's WWI..... what's it called?