“I will now cut one of these pills in two,” said Holmes, and drawing his penknife he suited the action to the word. “One half we return into the box for future purposes. The other half I will place in this wine glass, in which is a teaspoonful of water. You perceive that our friend, the Doctor, is right, and that it readily dissolves.”

“This may be very interesting,” said Lestrade, in the injured tone of one who suspects that he is being laughed at, “I cannot see, however, what it has to do with the death of Mr. Joseph Stangerson.”

“Patience, my friend, patience! You will find in time that it has everything to do with it. I shall now add a little milk to make the mixture palatable, and on presenting it to the dog we find that he laps it up readily enough.”