About jumping car - Connection Negative

I don't know if it is true or not,but I once read that Positive is really Negative and Negavite is really Positive.Maybe the Brits have it right? Visit a scrap metal yard once in a while where they buy old car batteries and you will probally see some batteries that have blown up,it isn't a pretty sight.When jumping another car battery,if you cover both batteries with a damp cloth,that is suppose to lessen the chance of a battery exploding.And be carefull when carrying a battery in your hands,just letting a battery drop on a hard surface can cause it to explode. cuhulin