〃
Kent considered a moment； then sat down by the telephone and gave a number to Central。
〃That you； Sylvester？〃 he called into the mouth…piece。 〃If Mrs。 Brewster comes to the office； telephone me at Mr。 Rochester's apartment； Franklin 52。 Don't let Mrs。 Brewster leave until I have seen her。〃
〃Yes； sir；〃 came the reply； and Kent hung up the receiver。
〃Had any luncheon？〃 he asked Nelson as the man loitered around。
〃Not yet〃 … Nelson's eyes brightened at the word。 It was long past his usual meal hour。
〃Run down to the caf on the first floor and tell the head waiter to give you a square meal and charge it to me；〃 Kent directed。 〃Order something substantial； you must be used up。〃
The man hung back。 〃Thank you； Mr。 Kent； but I don't like to leave here until my relief comes；〃 he objected。
〃That's all right； I'll stay in the apartment until you return；〃 and Kent settled the question by opening the door leading into the outer corridor。 〃Ferguson will be around shortly； so hurry。〃
Kent watched the man scurry toward the elevator shaft； then returned to Rochester's apartment and once more took up the telephone。 The operative's reluctance to leave the apartment unguarded had altered his plans somewhat。
〃Is this Dr。 Stone's office？〃 he asked a moment later； as a faint 〃hello；〃 came over the wire。 〃Oh； doctor； this is Kent。 Please come over to Rochester's apartment； I would like to consult you in regard to an important matter。 You'll come now？ Thanks。〃
The doctor kept Kent waiting less than five minutes。 The clock was striking one when he appeared； bland and smiling。 Hardly waiting for him to select a seat Kent flung himself into a chair in front of Rochester's desk and laid the pill box on the writing pad。
〃Now； doctor；〃 he began； and his manner gained in seriousness； 〃what； in your opinion； killed Jimmie Turnbull？〃
〃The post…mortem examination proved that he had swallowed aconitine in sufficient quantity to cause death；〃 Stone replied。 〃He undoubtedly died from the effects of that poison。〃
〃Is aconitine difficult to procure？〃 asked Kent。
〃It is often prescribed for fevers。〃 Stone made himself comfortable in a near…by chair。 〃Aconitine is the alkaloid of aconite。 I believe that in India it is frequently employed； not only for the destruction of wild beasts； but for criminal purposes。 The India variety is known as the Bish poison。〃
Kent started … Bish poison … was he never to get away from the letter 〃B〃？
〃Can you procure Bish in this country？〃 he asked。
Stone considered the question。 〃You might be able to purchase it from some Hindoo residing or traveling in the United States；〃 he said； after a pause。 〃 I doubt if you could buy it in a drug store。〃
Kent heaved a sigh of relief as he hitched his chair closer to the physician。
〃Did you prescribe a dose of aconitine for Mrs。 Brewster recently？〃 he asked。
〃I did； for an attack of rheumatic neuralgia。〃 Stone eyed him curiously。 〃What then； Kent？〃
〃Is this the box the medicine came in？〃 and Kent placed the cover in Stone's hand。
Stone turned the paste…board over and studied the defaced label。 〃I cannot answer that question positively；〃 he said。 〃The label bears my name and that of the druggist； but the directions are missing。〃
〃But the number's on it；〃 put in Kent swiftly。 〃Come； Stone； call up the druggist； repeat the number to him； and ask if it calls for your aconitine prescription。〃
Stone hesitated as if about to speak； then； reaching out his hand； he picked up the telephone and held a short conversation with the drug clerk of the Thompson Pharmacy。
〃That is the box which contained the aconitine pills for Mrs。 Brewster；〃 he said； when he had replaced the telephone。 〃Now； Kent； I have secured the information you wished； kindly tell me your reasons for desiring it。〃
It was Kent's turn to hesitate。 〃Do you know many instances where aconitine was used by murderers？〃 he questioned。
〃N…no。 I believe it was the drug used in the celebrated Lamson poison case；〃 replied the physician slowly。 〃I cannot recall any others just at the moment。〃
〃How about suicides？〃
〃It is seldom； if ever； used for suicides。〃 Stone spoke with more assurance。 〃I have found in my practice； Kent； that suicides can be classed as follows： drowning by the young； pistols by the adult； and hanging by the aged； women generally prefer asphyxiation； using illuminating gas。 But this is beside the question； unless〃 … bending a penetrating look at his companion …〃 unless you believe Jimmie Turnbull committed suicide。〃
〃That idea has occurred to me；〃 admitted Kent。 〃But it doesn't square with other facts which have developed； nor is it in keeping with the character of the man。〃
〃Men who suffer from a mortal disease sometimes commit desperate acts； not at all in accord with their previous conduct；〃 responded Stone gravely。 〃Come； Kent； you have not answered my question。 Why did you wish information about this box of aconitine pills prescribed for Mrs。 Brewster during her attack of neuralgia？〃
〃You have just stated that aconitine is not usually administered to murder a person；〃 Kent spoke seriously； choosing his words with care。 〃Do you wonder then； that I consider it more than a coincidence that Jimmie Turnbull should have died from a dose of that poison； and that the drug should have been prescribed for one of the inmates of the house he visited shortly before his death？〃
The physician sat upright； his face had grown gray。 〃Mr。 Kent；〃 he commenced indignantly； 〃are you aware what you are insinuating？ Are you； also； aware that Mrs。 Brewster is my cousin； a charming； honorable woman； without a stain on her character？〃
Kent set the bottom of the box containing the pills in front of the doctor。
〃I have found out that this box； with its dangerous drug； was left on the hall table in the McIntyre house； apparently any one had access to its contents； therefore my remarks are not directed against Mrs。 Brewster any more than against any person in the McIntyre household； from the Colonel to the servants。 I found these three pills at the McIntyre house this morning； how many did your prescription call for？〃
Stone picked up the small pills and； as he balanced them in his palm； his manner grew more alert。 Suddenly he dropped two back in the box and touched the third pill with the tip of his tongue； not content with that he crushed it in his fingers； sniffed the drug； and again tested it with his tongue。 His expression was peculiar as he looked up at Kent。
〃These are not aconitine pills；〃 he stated positively。 〃They are nitro…glycerine。 How did they get in this box？〃
Kent rubbed his chin in bewilderment。 The box bearing the aconitine label and the pills had all rolled out of the china umbrella stand； and he had taken it for granted that the pills belonged in the box。
〃I found them loose in the same receptacle；〃 he explained。 〃And concluded they were what remained of the aconitine pills which Grimes； the McIntyre butler； said he left on the hall table Sunday afternoon。〃
Stone smiled with what Kent； who was watching him closely； judged to be an odd mixture of relief and apprehension。
〃You could not have found more dissimilar medicine to go in this pill box； although the two kinds of pills are identical in color and size；〃 he said。 〃Aconitine depresses the heart action while the other stimulates it。〃
The physician's statement fell on deaf ears。 Raising his head after contemplating the pills； Kent had looked across the room and his glance had fallen on a wing chair； standing just inside the doorway of the living room； and thrown partly in shadow by the portieres。 The wing of the chair appeared to move。 Kent rubbed his eyes and looking again； caught the same slight movement。
Bounding toward the chair Kent saw that the brown shape which he had mistaken for part of the tufted upholstery was the sleek brown hair of a man's well…shaped head。 He halted abruptly on meeting the gaze of a pair of mocking eyes。
〃Rochester？〃 he gasped unbelievingly。 〃Rochester！〃
His partner laughed softly as Stone approached。 〃I have been an interested listener；〃 he said。 〃Let me complete the good doctor's argument。 Nitro…glycerine would have benefitted Jimmie Turnbull and his feeble heart； whereas the missing aconitine pills killed him。〃
Stone regarded him with severity。 〃How did you get in this apartment？〃 he demanded； declining the challenge Rochester had offered in addressing his opinion of Turnbull's death directly to him。
Rochester dangled his bunch of keys in the physician's face and smiled at his excited partner。 〃If you two hadn't been so absorbed in your conversation you would have heard me walk in；〃 he remarked。
〃Where have you been？〃 demanded Kent； partly recovering from his astonishment which had deprived him of speech。
〃I decided to take a vacation at a moment's notice。〃 Rochester spoke with the same slow drawl which was characteristic of him。 〃You should be accustomed to my eccentricities by this time； Harry。〃
〃We are；〃 announced Detective Ferguson from the hallway； where he and Nelson had been silent witnesses of the scene。 〃And we'll give you a chance to explain them in the pol