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Show --- kj o 1 Fw rv WV Vvvv ANi VWj tfWw A AWV V) A AWV ywuW WAjo ftftBn jf&Hm ygfo&vx p At Left the New Electrocardiograph Electro-cardiograph Which Detects Sounds Heretofore Inaudible and Records Them on Phonograph Kecords and on a Graph. Below The Human Heart W hich Has Four Chambers, Two Auricles or Receiving Chambers and Two Ventricles or Driving Chambers. RA, Right Auricle; SVC, Superior Venae Cavae; IVC, Inferior Vena Cava; RV, Right v Auricle; PA, Pulmonary ; Arteries; PV, Pulmonary .?. Veins; LA, Left Auricle; LV; Left Ventricle; SAy Systemic Arch; C, Carotid; SCL, Left Subclavian; DA, ' Dorsal Aorta; Tit, Windpipe; BR, Bron- -Tv ial Tube; BV, Blood-Asf" Vessel. KjxV - -- " Sir m: .m Above-Cardiograms Showing: How the Heart S hips and Jumps Under Three nifferent E"i"tio: (1) Over-Exerlion, (2) Nicotine roisoning, (3) Anger. Below-Normal Heartbeat as Registered W by the Electrocardiograph. A so. ? -r-x. t nol3e Makmg ; heart liiroos; ries noises other than its own 'jit through vibration. Put y"ur car to 'ifc this desk. Hear that noise? Now ''jK try that wall put your ear close to it. Do you hear that dull roar? Put the end of your finger in your ear do you hear that roar? Well, that's the muscle noise of your V fingers, j y' "This was the problem that confronted con-fronted us when the experiments icgan the problem of separating the loises of the heart from all other sounds, n certain forms of heart disease the lelicate murmurs which make the pres- "Furthermore, the phonographic records makes "Nl it possible to record the patient's heart sounds pe" over a long period of time. Suppose a doctor S. examines a patient he has not seen for a ye.".r. Is his heart sound the same as before? Until now this has been a matter of memory. With M- phonographic records of the electrical atetlio- jk., scope he can secure an exact comparison. "Again these doctors who are confmtitM ? ::. F unusual heart conditions for the r?.t tiic no longer compare the actual soun i v.'.tii i- feeble representation in a book lie '..iii t;-rr . on j his phonographic record-part of his te'-'t b-'.c and will hear accurately the her.rt souiid ol tho - ( disease he is searching for. "The electric stethoscope, its equipment com- f ' bining the latest lessons of radio and t'le;hony, can be rolled into the room like a t- cart, for ,j portability is one of its features. Again, when a patient cannot be moved an electrical con- (Vyi nection from his bedside will permit students in the lecture room to hear his heart beats." I y kl." AF disease, death's most n I effective agent, which, dur-1 dur-1 f ing the jjast twenty-five I I years has shown for some sections Tell ike Secrets) sounds and recording them on phemograph iD A records so delicately constructed that only the heart sounds can be heard when the special records are played. The electro-cardioeraoh. which is oDerated ence or. the disease evident are annosi ciuaKtu by the other noises made by the muscles of the patient or the operator's fingers, and so on. "The electric stethoscope employs a filter to strain out these extra noises and a vacuum tube amplifier to amplify the sounds it is designed to retain. This permits the smallest heart sound to be heard. A-sT I of the country e.u increase in its P"Vi number of victims as high as sixty per cent, nviy now be checked in its ravages by jX f'sC ft d'3C0vcry acclaimed by the medical world as J-rN( Jj one of the most important steps taken by sci- r"Nx enlists since Harvey discovered the circulation o ?Vv the blood m arly tluve hundred years ago. y With the aid of a new electrical stethoscope combined with the features of both the cardiograph cardio-graph and the phonograph physicians can now y ir tnc i'hst time in the history of the world Uf? listen to the full sound of a human heart throb TyJjC at the same time that the actual movement of the organ is being recorded. fJST" The instrument that makes all this possible 's the Product of seven years' work by a number of physicians in co-operation with other scientists. VVcf By its us:- physicians expect to be able to reduce 4 by the thousamls the number of deaths from heart di pease through an early diagnosis and treatment two prima factors in the fight ; against this deadly malady. This new electrical stethoscope coupled with an amplifier that can increase sound one hundred million times was recently demonstrated before the members of the New York Electrical Society by H. Clyde Snook, a staff engineer of the Bell Telephone Lab ora tones. Those present said that they listened to heart beats that sounded like blows of trip hammers and moving muscles fibres that roared like subway trains. Mr. Snook produced the noises by the simple expedient ex-pedient of holding the stethoscope against his chest and jaw in succession. Others said that at times the heart throbs sounded like a portly woman of middle age walking upstairs in her bedroom bed-room slippers. Although the demonstration was entirely a serious procedure broad grins spread over the faces of the engineers and physicians as they heard the ludicrously graphic soiiilJs 1uX came from the loud speaker. Phonograph records were also ir.rf'.n o humsn heart beats by Dr. Richard Cabot, of i : vi'vard Universityt working in conjunction v.v,l". . . j. J. Gamble, of Johns Hopkins, and Mr. Sno k. These scientists have specialized on li:r- w-paratus w-paratus for separating heart sounds fiont oLiur somev.'hat on the principle by which photographs are sent by telephone, plays a needle of light up and down over the surface of a smoked drum, so that the movements of the heart are visible and are permanently recorded on paper graphs. Physicians who treat heart disease say that in many cases they have always found it most difficult diffi-cult to jud'ie ih?. exact condition of a patient's heart, vIJc'i could not be seen, by sounds which could bo heard by but one person at a time. The electrical stethoscope and its auxiliaries, however, how-ever, have now removed all such obstacles that prevented the making of an1 immediate and correct cor-rect diagnosis. The ordinary stethoscope, the experimenters point out, never has been able to transmit all heart sounds accurately on account of numerous other noises. Up to the present physicians in recording re-cording data about cases of heart disease have had only a "tone" of heart sounds based on a ea' 1 'rmrvl cf the opening and closing of the letL'r "V'' a rough method, indeed. "The old acoufac stethoscope is to the electric one what a vatcr pipe is to a telephone line," sjiys iWr. KiMrk in do.-cribing the instrument and its auxiliaL-;, You've heard a boy talk through a waterspout, yo'ln: down from the roof. The sound was mufiied and distorted by passing through the pipe. "Vibration exiss everywhere. Everything has its particular noise, speaking generally, and car- |