An instance of the way in which one small fact may give conclusive proof that a crime has been committed is afforded by the trial of Swan and Jefferies in the early part of last century. The prisoners, who were indoor servants, had committed a murder and then raised an alarm with the object of throwing the suspicion upon burglars, who they alleged had broken into the house. But an examination of the grass outside the house showed that although dew had fallen heavily through the night there were no indications of its having been disturbed by footsteps. This piece of circumstantial evidence led to their arrest, and they were subsequently convicted and executed. Equally convincing were the clues that led to the arrest of Courvoisier in 1840, for the murder of Lord William Russell, who was then seventy-five years of age. The prisoner had only been in the service of the murdered man for a short time. He stated that on the night before the murder he had left his master reading in bed, as was his frequent custom, and a fact in support of this was that the candle had burned down to the socket. Early in the morning the housemaid found the silver plate scattered about the room, and various articles of value tied up in bundles, as though burglars had broken into the house and had been interrupted in their work. She called Courvoisier, and he appeared almost immediately, fully dressed, and going into the room of Lord William Russell found him with his throat cut. On a door were marks which indicated that it had been broken in by the supposed burglars, but closer examination showed that the damage had been done from the inside. In addition to this, any burglars entering the house through this door must have passed over a wall, and this was found to be thickly coated with dust which had not been disturbed. For a long time no trace of the missing valuables were discovered, but finally after a thorough search of the premises, some of the money was found hidden behind the skirting in the pantry of the accused, while later on the stolen plate was discovered in the keeping of a man with whom Courvoisier had formerly lived. Mainly on the circumstantial evidence of these facts the prisoner was convicted; afterwards he made a full confession of the crime. Clever deductive reasoning was also shown in the following case, in which the author of a shooting outrage that occurred in 1831 at Ayr was discovered in a singular manner. Someone had maliciously fired a gun into a church, and had hoped to escape detection. It was noticed, however, that some of the bullets, after having passed through the windows, had left a mark upon the wall opposite. By drawing a straight line between these marks and the holes in the windows, and extending the line outside the church, the other end was found in a window on the other side of the street. Subsequently other proof was obtained that the gun had been fired from this window.