At some time or the other the mercury in your candy thermometer is going to separate heres how to fix it:

Get a pan full of water and ice add 1/4 cup rubbing alcohol. Have handy a thick paperback book or notepad.Place the thermometer in the ice water until the separated portion stops dropping. Take it out and tap it numerous times on the book or pad. You will know you are being effective when the separated mercury starts to break up and begin looking almost like a barber pole. Keep doing this process until all the separated mercury has returned to the bottom of the thermometer you will have to re-calibrate the thermometer after you do this.

Too Calibrate:
Place the thermometer in a pot of water. Bring the water to a boil. Watch your thermometer to see at what temp the water boils. Altitude variations
are going to effective at what temp the water boils. Boiling water temp is 212F. At my altitude I have to subtract 12 degrees from my recipe temp.
So if for example your water boils at 204 than you need to add 8 degrees to your recipe temp.

I know this is boring info and proably no one cares but I just wanted to let everyone know of the problems I have and how I corrected them so they won't have the same problem agian.

Darn good info there SugarCreations. Think I will print it and save for future use never had the problem but aye who knows.