"I thought so. This woman heard your car coming, and later on saw it. She doubtless slipped out of the back room, where she had just stabbed her victim, and had the eye--this seems to be the motive for the commission of the crime--in her pocket. She could not walk into the road without running a chance of meeting you, so she sprang up the stairs yonder"--he pointed to the steps, which clung to the wall on one side and had a light railing on the other--"and took refuge in the bedroom. When she heard you enter the back room, she came down turned the key, and ran away with your car." "Humph!" said I, after a pause, "permit me to put you right on one point, Mr. Inspector. I believe that the woman was in the back room when I entered the shop, for when I tried the door in order to find someone, it was locked." "Really!" Dredge made a hasty note. "Was the key on the outside?" "I don't remember. All I know was that I could not pull open the door." "She would not have had time to change the key from the inside to the outside," mused the Inspector. "I daresay the key all along was on the outside, as it is now." He glanced at the door leading into the back room, and sure enough there was the key. "Possibly, she shot the bolt--there is one on the hither side of the door, as I noticed. Well?" "Well, while I was filling the tank of my car with petrol she must have emerged, and--as you say--unable to escape without observation by the road, she must have slipped upstairs. When I found the door open on trying it for the second time, I entered the back room, attracted by the last moan of the dying woman. Then she--the murderess, I mean--must have come down, and after softly turning the key, have gone off in my car." "But why should she leave the car in a field?" asked Cannington. "To the more easily escape," said Dredge, raising his eyebrows. "A car with a number could easily be traced. She took it as near Murchester as she dared, then abandoned it, and walked to the town. That is my theory, and then she could either remain in Murchester or take the train to some other place. It will be a hard matter to find her, as she has concealed her trail very successfully." "She might have left some evidence behind in the car," I suggested. Dredge shook his head. "I examined the car myself this morning," he remarked. "There is not a vestige to show that any woman occupied it. She has not left even so much as a pin behind." "Pardon me; she left a hat-pin!" "Yes," said the Inspector grimly, "in the heart of the unfortunate Mrs. Caldershaw. But your car is still in that field near Murchester, Mr. Vance, and I shall leave you to take it away. I don't know how much it is injured." "Last night you said that it wasn't much hurt," I said hastily.