In the long hallway of dressing rooms Marilyn stopped, grasping the k.n.o.b of her door. "It'll only take me--" she began.

Then her face went white as the concrete of the floor, and that was immaculate. An expression which might have been fear, or horror, or hate--or all three, spread over her features, transforming her.

Following the direction of her stare, I saw Shirley down the hall, just as he stopped at his own door. He caught her glance suddenly, and his own face went red. I thought that his hands trembled.

Marilyn wheeled about, lips pressed tightly together. Throwing open the door, she dashed into her room, slamming it with a bang which echoed and re-echoed up and down the little hall. She had forgotten our presence altogether.

XIV

ANOTHER CLUE

Kennedy looked at me quizzically. "I guess we'd better not wait for Miss Loring to initiate us to McCann's," he remarked.

We found our way to the courtyard, and were headed for the gate when a young man in chauffeur's cap and uniform intercepted us. I had noticed him start forward from one of the cars parked in the inclosure, but did not recognize him.

"May I speak to you a moment, Professor Kennedy--alone?"

"Mr. Jameson here is a.s.sociated with me, is a.s.sisting me in this case, if it is something concerning the death of Miss Lamar."

"It is, sir. I saw you out at Tarrytown yesterday. McGroarty is my name and I drove one of the cars the company went in. They were pointing you out to me, and I'd read about you, and just now I says to myself there's something I ought to tell you."

"That's right." Kennedy lighted a cigar, offering one to the chauffeur.

"I'm not supernatural and often I'm able to solve a mystery only with the help of all those who, like myself, want justice done."

"Yes, sir! That's my way of looking at it. Well"--McGroarty blew a cloud of smoke, appreciatively--"I do a good bit of driving for these people, and this morning it was cloudy and dull, no good for exteriors, but yet sort of so it might clear at any moment, and so I was ordered.

I brought my car and left it standing here in the yard while I went over to McCann's--the lunch room, you know--for a cup of coffee. When I came back"--again the cigar--"there still was nothing doing, and so I thought--you know how it is--I thought I'd clean up the back of the old boat, to kill time, not saying it wasn't needed. So I took out the cocoa mat to beat it and what do I find on the floor--between the mat and the rear seat it was, I guess--but this."

He handed Kennedy some small object which glinted in the light. Looking closely, I saw that it was a peculiarly shaped little gla.s.s tube.

"An ampulla," Kennedy explained. "It's the technical name the doctors have for such a container."

"It must have been between the mat and the rear seat," the chauffeur repeated. Then he discovered that his cigar was out. He struck a match.

Kennedy turned the bit of gla.s.s over and over in his hand, examining it carefully. I felt rather fearful, wondering if it might not contain some trace of the deadly poison which had so quickly killed Stella Lamar. I even half expected to see Kennedy find some infinitesimal jagged edge or point which could have inflicted the fatal scratch. Then I realized that McGroarty had handled the thing with impunity, perhaps had carried it about half a day.

Kennedy took his scarf pin. On the outside of the little tube there was no trace of a label or marking of any sort. All about, on the inside, however, the gla.s.s was spotted with dried light-yellow incrustations, resembling crystals and at first apt to escape even the sharpest scrutiny. With the pin Kennedy scaled off one of these and put it under his pocket lens. But he came to no conclusion. Rather puzzled and nettled, he dropped the tiny bit of substance back into the tube, then replaced his pin in his scarf, and stowed this latest bit of possible evidence in his pocket carefully.

"How do you suppose it got in the car?" he asked.

"Some one must have dropped it and it must have rolled in that s.p.a.ce by the edge of the mat," replied the chauffeur. "There was just room for it, too! I never would have noticed it without taking up the mat."

"It couldn't be broken, by being trampled on?"

"Nope! Not a chance!"

"How long could it have been there?"

"Two or three or four days--since I cleaned up last."

I remembered the cleverness shown by the guilty person in placing the needle in the curtain. It seemed unlikely that this could be an accident. "Isn't it possible," I suggested, "that this is a plant; that the tube was put there deliberately, to throw us off the track?"

"It's quite likely," he admitted. "On the other hand, Walter, the very smartest criminal will do some foolish little thing, enough to ruin the most careful plans and preparations." He turned to McGroarty. "Who rode in your car yesterday?"

"Mine's the princ.i.p.als' car," boasted McGroarty. "Going out I had Miss Lamar, Miss Loring, Mr. Gordon, Mr. Shirley, and Mr. Werner. Coming back Mr. Werner was with you, and Miss Lamar--well, there was only Miss Loring and Mr. Gordon and Mr. Shirley."

"Did you notice how they acted?"

"They never says a word to each other on all the trip back, but I didn't think it strange after what happened, although usually they're always joking and laughing."

"You brought the three to the studio here?"

"Yes. They had to get out of make-up."

"Did you leave the car then?"

"No, I hit it right for the garage."

"Were you away from the car at Tarrytown?"

"Sure! That was a long wait. Peters, Manton's chauffeur, and I found a couple of horseshoes and we were throwing them most of the time."

"How long was the machine alone here in the yard this morning?"

"A couple of hours, maybe. I knew the old boiler was safe enough, and that if they wanted me they'd look over in McCann's."

"Well," Kennedy extended his hand, "I thank you, and I won't forget you, McGroarty."

As soon as the chauffeur was out of earshot I faced Kennedy rather eagerly, to forestall him if he had arrived at the same conclusion as myself.

"See! It's just as I thought yesterday!"

"How's that, Walter?"

"Werner! He rode out in that machine, but not back. In Manton's car he was worried all the time. He probably knew he had dropped the tube.

Then he hurried up ahead of us and wiped the needle--" I stopped, lamely.

Kennedy smiled. "See, you're jumping at conclusions too fast. You remember now that we decided that the towel has nothing directly to do with the poison. In a way you cannot a.s.sume that this ampulla has, either, although I myself feel sure on that point. But in any case no one is eliminated. It is true Werner did not return in the same automobile. It is also true that he had little opportunity to drop it while others were in the car with him. When McGroarty was away from the car anyone could have lost it, or--as you suggested a moment ago--planted it there deliberately to divert suspicion."

I felt the beginnings of a headache from all these confused threads of the mystery. "Can't--Isn't there anyone we can say is innocent, at least, even if we cannot begin to fasten the guilt upon somebody?" I pleaded.

Kennedy shook his head. "At this stage the one is as hard as the other.

I consider myself lucky to have collected as much material as I have for the a.n.a.lysis of the poison." He tapped his pocket significantly.

"Yoo-hoo!" A frankly shrill call in a feminine voice interrupted. We both turned, to see Marilyn Loring hastening toward us.