266 



.NATURE 



[December 29, 1910 



and Miiller worked about 1856, Donders about 1872 ; 

 and at last there were the elaborate researches of 

 Engelmann from 1873 to 1877. Gotch and Burdon 

 Sanderson studied the phenomena of inhibition in the 

 heart of the tortoise in 1877; Bernstein, du Bois Rey- 

 mond, Engelmann, Hermann, and Burdon Sanderson 

 used the rheotome between 1868 and 1887. Then followed 

 the invention of the capillary electrometer by Lipp- 

 mann in 1873 ; it was soon used by Engelmann and 

 Mare}', and in 1883 it was employed in research by 

 Burdon Sanderson and Page. Waller, in 1889, was 

 the first to employ the instrument in the investigation 

 of the human heart. The actual oscillations in the 

 tube of the capillary electrometer were photographed 

 on a rapidly moving plate, so as to produce a cardio- 

 gram, and with this invention the names of Burch 

 and Burdon Sanderson will be always associated 

 (1890). In more recent times we have the invention 

 of the string galvanometer by Ader in 1897, ^^^ P^^"- 

 fected by Einthoven, until it must be regarded as by 

 far the most sensitive instrument for the purpose. 

 The instrument, as now constructed, is much more 

 delicate than the original instrument of Ader, while 

 tlie apparatus had been made complete by the photo- 

 graphic registering apparatus made by various in- 

 genious workers in optics and mechanics. 



The accurate interpretation of the electro-cardiogram 

 owes much to Waller, who established important 

 leading principles on which monophasic and diphasic 

 currents can be explained. He also gave a schematic 

 representation of the action currents that can be led 

 off from the living human heart (Fig. 16, p. 45). In 

 the work under notice, there is a full description of 

 the principle and mechanism of the string galvano- 

 meter, and an analysis of the curves produced from 

 it (p. 64). The introduction of the quartz fibre has 

 most materially increased the delicacy of the instru- 

 ment. There can be no doubt that only an expert 

 can use the instrument In a satisfactory manner, as 

 is well illustrated by a study of the diagram of the 

 apparatus in an actual experiment in Fig. 28, p. 89. 

 This method Is much more complicated than the 

 simple galvanometer experiments once in vogue in 

 every physiological class-room or laboratory. 



Kraus and Nicolai then give a thorough analysis 

 of the electrocardiogram, showing in the diphasic 

 effects groups of electrical oscillations In the curve 

 which are associated with the contractions of the 

 auricle, with those of the ventricle, and with changes 

 occurring also during the diastole of the ventricles 

 and the filling of the auricles. The time relations of 

 all those phenomena can also be accurately deter- 

 mined; Indeed, an Insight is obtained Into the 

 phenomena of the living beating human heart not 

 otherwise possible. They also endeavour to show that 

 those phenomena may be explained or accounted for 

 by our knowledge of the muscular arrangements of 

 the walls of the heart. Without mentioning the old 

 researches of Borelll or the more recent dissections of 

 Pettigrew (to be seen in the museum of the Royal 

 College of Surgeons, Lincoln's Inn Fields), they de- 

 scribe the spiral arrangement of the fibres, the relation 

 of many of the fibres to the papillary muscles, the 

 NO. 2148, VOL. 85] 



fibres of Wenckebach (1901) between vena cava and 

 the auricle, and the bundle of His (1893) between auricle 

 and ventricle. Nearly thirty years ago there appeared 

 the classical research of Gaskell (1883) on the heart of 

 the tortoise, which showed the passage of impulses 

 from auricle to ventricle, and was tTie beginning 

 of much work of great clinical as well as physio- 

 logical Importance. The analysis of many electro- 

 cardiograms is given with great care and thoroughness 

 by the authors In chapters vl. to x., and to those the 

 reader must be referred. . 



The second portion of the work relates to the \ 

 clinical use of the string galvanometer in the investi- 

 gation of diseases of the heart and of the circulation. . 

 When one considers that the complete apparatus costs 

 from 200Z. to 250Z., and that a special knowledge of 

 electrical appliances is required, it will be evident 

 that the method cannot be expected to come into 

 general use, even in the wards of a well-appointed 

 hospital. Physicians will depend more on mechanical 

 appliances for registering the movements of the 

 various pulses (both venous and arterial) and of the 

 heart itself, a method of sphygmographic investiga- 

 tion that has received a new lease of life by the 

 labours of Mackenzie and others. At the same time 

 it must be admitted that the electrical phenomena give 

 a glimpse of phenomena actually happening In the 

 heart which would escape detection by the mechanical 

 method, as, for example, slight changes In the beat 

 of the auricles, and some phenomena which may 

 account for want of rhthym, as when the auricles 

 and ventricles do not beat in the normal consecutive 

 order. The time relations can also be accurately 

 noted. The authors give many cardiograms well 

 worthy of the study of physicians. These must not be 

 confounded with the tracings that, by other methods, 

 may be obtained of the vibrations of the sounds of the 

 heart. Science must advance, but It is rather dis- 

 heartening to be obliged to take the view that these 

 elaborate researches have very little to do with the 

 actual treatment of diseases of the heart, and the 

 sufferer whose heart Is beating arhthymically will find 

 cold comfort in the certain knowledge that there is 

 some kind of fatty or other degeneration in the fibres 

 of the bundle of His in his cardiac organ. 



Since the above was written a valuable paper has 

 appeared in Heart by Dr. Thomas Lewis and B. S. 

 and Adele Oppenhelmer on "The Site of Origin of 

 the Mammalian Heart Beat; the Pace-maker in the 

 Dog." The researches have been carried out with 

 the string galvanometer, with special reference to the 

 electrical relations of the collection of specialised 

 tissue at the upper caval end of the sulcus terminalis 

 of His. The tissue, or node, as it may be termed, 

 was discovered by Keith and Flack. Dr. Lewis and 

 his co-workers find electrical evidence to show that 

 it Is the site of primary activity, that Is to say, from 

 it impulses radiate that are the cause of the co- 

 ordinated heart beat. This result, long sought for 

 by other observers, is an important addition to cardiac 

 physiology, while it illustrates the value of the use 

 of the string galvanometer. 



John G. McKendrick. 



