A firefighter came home from work one day and told his wife, "You know, we have a wonderful system at the fire station: Bell 1 rings and we all put on our jackets, Bell 2 rings and we all slide down the pole, Bell 3 rings and we're on the fire truck ready to go.
From now on when I say Bell 1, I want you to strip naked. When say Bell 2, I want you to jump in bed. And when I say Bell 3, we are going to make love all night."

The next night he came home from work and yelled, "Bell 1!"

The wife promptly took all her clothes off.

When he yelled "Bell 2!", the wife jumped into bed.

When he yelled "Bell 3!", they began making love.

After a few minutes the wife yelled "Bell 4!"

"What the hell is Bell 4?" asked the husband.

The wife said, "Roll out more hose. You're nowhere near the fire."