Day after day， a small blue truck speeds along the roads of Denmark's island of Funen. A big dark dog sits beside the driver， looking at him as if listening to his instructions. Whenever the truck goes by， the people of Funen turn and stare， some in wonder， others in recognition. For on its side are printed the words Sporhunden Rolf (Rolf， the Tracking Dog) and a telephone number.
Yes， the passenger in the blue truck is Rolf， a dog that is hired to find things people have lost. Within seven years， Rolf and his owner have found close to $400，000 worth of missing items. Among them are watches， jewelry， tools， money， cows， geese， pigs and other dogs. And what is Rolf's secret? His sensitive nose!
The owner of that nose is a ten-year-old German Shepherd. And the owner of the German Shepherd is Svend Anderson. Together they answer the 600 to 700 calls for help that they get each year. Four out of five times they find what they are asked to look for.
Whenever the telephone rings in Anderson's house， Rolf is instantly alert. He dashes to the truck， eager to be off.
On the way， Svend repeats again and again the name of what they are going to look for. So， by the time they arrive， Rolf is ready to get to work. He circles， backtracks and circles again. This he continues until he picks up the faint scent of an object lying in a spot where it doesn't belong.
One spring I went to Funen to make sure that Rolf's detective work was not some kind of fairy story. Over coffee and cakes Svend and I talked and watched Rolf. The dog's stare was mysterious. He seemed alert yet calm. The telephone rang， and then I heard Svend saying， "A wallet? I can't promise， but we'll do our best."
An hour later we were in a park， tramping among the trees with Axel Jensen， the man who had phoned. Jensen had lost his wallet wouldn't be easy!
For half an hour Rolf roamed in wide， broken zigzags. Ocationally， Svend would call him back or tell him to keep looking. No wallet was found.
We drove to another part of the forest. Again Rolf roamed with his nose to the boggy earth. Svend encouraged him from time to time. I don't know at what moment we began to notice that Rolf was padding about in small circles. Svend was now standing at the edge of a ditch. He was tense， as if giving orders that only Rolf could hear.
Suddenly， Rolf began to paw the soft earth. He stopped， looked about and scratched again a few feet away. Then he changed his mind and began to dig further to the right， All at once he trotted out of the bog， head high. He was holding sth dark in his mouth. It was the wallet! Jensen roared with surprise and joy.
"Tell me， Svend，" I said later， "how on earth does a dog go about finding a wallet five by seven inches in a huge forest covered with undergrowth?"
Svend smiled as he replied， "I knew there was nothing in the first 75 acres because of Rolf's lack of interest. But in the swamp I could tell from the way Rolf acted that he had picked up a trail. The scent had reached him through the air from the spot where the wallet was dropped ten days ago."
How did Svend come to own this dog with a detective's nose? He picked Rolf from a litter of seven pups because Rolf had the biggest head and snuffled more eagerly along the ground.
When he was only five months old， Rolf found his first missing object. It was a neighbor's watch. After a year's careful training， Rolf became a professional， ready for work.
One time Svend had an unusual call. A visitor to a cattle show sneesed so hard that he lost a gold filling. Did Rolf find it? Of course! And the speck of gold lay several yards from the place of the sneeze， in ground that had been trampled by hundreds of feet.
Another time Rolf saved an 11-year-old girl from a stern scolding. She was playing with her grandmother's fine watch when she lost it in ahaystack. About 50 childen were turned loose to look for it. No luck. Next day the police came with two dogs， both failed.
Nine days later， Rolf was sent for. Paying no attention to the haystack， Rolf began to nose about in a pit some distance away. He found the watch in a matter of minutes. Someone had dumped a forkful of hay from the stack into the pit.
Rolf does not always meet with success， but he tries very hard. Sometimes he tries too hard. Once when Svend scolded him sharply for failing to find a lost watch， Rolf crept away. He returned a little later in triumph with a watch in his mouth. Close behind him was an angry， half naked man. He shouted： "I was getting dressed when this dog poked his head in the door and lifed my watch from the table. He's a thief!"
Nothing ever gets lost in the Andersen house. Rolf picks up coins， nails， buttons， all without being told. To show me this， Svend put a spoon on the floor and then called Rolf in from the next room. The dog was ordered to lie down. We went on talking. Rolf couldn't stand it. In a few minutes he got up， seized the spoon in his mouth and brought it to his master.
Andersen and Rolf definitely are partners. Between them there is a deep understanding. When Rolf fails on a job， Svend lies awake that night. In his mind he goes over and over the ground they seached. Often he gets out of bed and drivers with Rolf to the scene of their failure. There they go hunting again by flashlight.
"The night is quiet，" he says， "It's a good time to hunt a thing that is lost." Often they find it. "When we find something，" says Andersen， "there's no feeling like it. I don't know who is happier， Rolf or me. Then I can just relex-until the telephone rings again!"