A rich man named Stuart Laidlaw had been counting his money. 
When he finished, he accidentally left a $1000.00 bill on his 
desk but when he returned for it a short while later, it was 
gone. Only two other persons could have seen the bill. One was 
the cook; the other was the gardener. The cook told him that she 
had hidden it for safekeeping under a green book that was on the 
desk. But when they looked the bill was not there.  The gardener 
said he had found the bill where the cook had left it. He had 
placed it inside the book, where he thought there was less 
chance that somebody would find it. He had written down the page 
numbers so that he would not forget them. The bill was between 
pages 45 and 46, he said.  But when they looked, there was no 
money in the book. After Mr. Laidlaw had talked to the cook and 
the gardener, he called the police. He was sure he knew who had 
taken the money. Who was it, and how did he know?

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