A mathematics grad student in the U.S. spend a semester studying overseas in Germany. When the semester ended he decided to travel to London, England before heading home so he could visit historical sites associated with Isaac Newton, the inventor of Calculus.
Before leaving London he visited a local used book store to check out the mathematics section. He finds a hand written manuscript that appeared to be very old. As he looked through it he realized that the subject covered seemed to be the note on calculus, and the signature appeared to be that of Isaac Newton. He check the price and it was only 2 pounds.
He figures the book is probably worth millions of dollars so he decides to buy the book. He asked the clerk "Why do you have it marked down to just 2 pounds?".
"Well, we have had it on the shelf for years and nobody every bought it. We're just happy to sell it so we can put something else on that shelf."
He finally gets back to the U.S. and he calls his buddies from the airport. "You've got to meet me down at the bar, drinks are on me, and I'll be there in an hour."
So he gets to the bar, meets his buddies and starts to tell them about how he found this handwritten manuscript, signed by the great Isaac Newton. He explains that it is probably worth millions of dollars - and just then he realizes he left the book in the back seat of his car, in plain view. He gets a sinking feeling in his stomach because he knows that someone could break the back window and steal the book. She he goes running out of the bar.
He gets to the parking lot, he sees his car, and sadly notices that the back window is broken out. He is almost afraid to look in the car, but decides he has to look sooner or later anyway. He finally works up his courage to look - and do you knnow what he saw?
Someone had busted out the back window - and threw three more math books into the back seat!