An intelligent thief

Mr. Grey had a nice shop in the main street of a small town. He sold jewellery, watches, clocks and other things like those. All went well for some years, and then Mr. Grey’s shop was broken into at night twice in a month, and a lot jewellery was stolen each time. The police had still not managed to catch the thief three weeks later. So Mr. Grey decided that he would try to do something about it. He, therefore, bought a camera, fixed it up in his shop so that it would photograph anyone who broke in at night, and put some very cheap jewellery in front of it for the thief. 

A few nights later, the thief did come again, but he did not touch any of cheap jewellery that Mr. Grey had put out of him. He took the camera. It was worth 150 pounds. 

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