The Case of the 30-Carat Emerald

The theft of the Emerald occurred under circumstances most
embarrassing to Lawrence Johnson, owner of the 30 Carat Emerald. 
Johnson had been having a house party at his home in Barrington. 
There were five guests: Shirley Simmons, Lawrence’s new girlfriend;
Charles and Patricia Knightley, Charles is President of their Homeowner’s
Association; Michael French, Johnson’s best friend; and Doris Moore,
Michael’s girlfriend.

Lawrence Johnson,
the host, was careless. He had left the emerald in a small black lacquer box on
a table in the living room.  Johnson
had been playing telephone tag all week with someone in New York. When the
person in New York finally reached Johnson he left the lacquer box on the table
and hurried out to the library of the Johnson Mansion to take the call. 
When he returned in five minutes, the box was empty. Mary Dempsey, the
maid, had been in the room during Johnson’s absence. Mary was the maid at the
Johnson Mansion for thirty years and was beyond supposition. Mary said, “That
she saw nothing.”  For two hours
during dinner Mary searched the entire Johnson Mansion on the theory that the
jewel had been accidentally lost.  But
at last, Johnson was compelled to face the truth. 
Someone had taken it.

Johnson would not
call the Barrington Police. Absolving everyone from blame in the matter except
himself and insisting that he must have dropped it from the box, he stopped
further discussion of the subject and Mary cooked up the Bananas Flambé Dessert
tableside. This gave Johnson, who is something of an amateur detective, a chance
to examine the lacquer box carefully in the library.

The black lacquer
box was highly polished.  On the
outer rim of the inside cover he discovered a remarkably clear thumbprint
which was not his own.  He sprinkled
it with the white powder used to bring out fingerprints on surfaces. 
Then he set the box carefully aside.

Johnson knew that
none of the company had laid hands on the inside when he had first shown it to
them.  He figured that this must be
the thumbprint of the thief.

After dessert
Johnson’s dinner guests left. Johnson told Mary to touch nothing. 
Johnson went directly to the dining room to examine the crystal ruby red
water and wine goblets. Each goblet, bearing a different thumb mark, Johnson
dusted the goblets with the white powder.  Each
goblet was labeled for purposes of identification.

Below is a
reproduction of the thumbprint on the lid of the black lacquer box and the
guests thumbprints left on the crystal goblets.