April 13, 1876] 



NATURE 



471 



facturers are beginning to feel indifferent with regard to 

 exhibitions, that the Vienna Exhibition in the past and 

 the Philadelphia Exhibition in the present years, have 

 been absorbing their energies, the Committee think that 

 they have reason to be contented with the results ob- 

 tained. This view is strengthened by comparing the above 

 numbers with those of 127 exhibitors only who repre- 

 sented German science at Vienna. The Committee express 

 themselves greatly obliged for the assistance given by 

 the Lord President of the Council of Education, the Duke 

 of Richmond and Gordon, the Vice-President, Viscount 

 Sandon, the Director of the South Kensington Museum, 



Mr. Cunliffe Owen, and to the Government and Officers 

 of the German Empire and of Prussia, notably to the 

 Ministers of Education, Dr. Falk, of Commerce, Dr. 

 Achenbach, of War, General von Kamecke, of Marine, 

 to the head of the General Staff, Count Moltke, to 

 the Postmaster- General, Dr. Stephan, and also to the 

 Royal Library, to the Royal Academy of Science, and to 

 the German Chemical Society. The Committee con- 

 clude by claiming the assistance of the German Empire 

 for the production of a systematic and critical report on 

 the scientific treasures of all nations that will be exhibited 

 in London. 



ON A MODIFIED CARDIOGRAPH 



Tr\R. A. L. GALABIN, whose investigations with the 

 -*-^ sphygmograph and cardiograph we have had the 

 opportunity of noticing on former occasions {vide Nature, 

 vol. xii. p. 275), has introduced a modification of the car- 

 diograph, a woodcut drawing of which, through the kind- 

 ness of the Council of the Royal Medico- Chirurgical 

 Society, we are able to reproduce from their " Transac- 

 tions." 



The cardiograph of Marey is too well known to require 



description ; suffice it to say that it depends for its action 

 on the transmission through air-filled tubes of movements 

 from one stretched elastic membrane to another. In it, 

 therefore, errors originating in the tubes are introduced ; 

 and these, from practical experience, are found to be con- 

 siderable. More than one physiologist has obtained far 

 more satisfactory " cardiograms " by applying the sphyg- 

 mograph, which was originally constructed by its in- 

 ventor — SL Marey — for the purpose of recordin;^ the 

 movements of the pulse at the wrist, upon the chest-wall, 

 in the intercostal spaces. This instrument, when thus 



applied, reproduces in a most faithful manner the move- 

 ments of the chest-walls as there produced by the sub- 

 jacent heart in action ; and in the healthy subject any 

 accessory apparatus is rarely reeded for the satisfactory 

 production of the tracings. 



In many pathological conditions, and in the healthy 

 subject when the cardiac movements are more than ordi- 

 narily powerful, the movements of the heart are trans- 

 mitted to the neighbouring ribs, on which the sphygmo- 

 graph has to be supported, as well as to the more yielding 

 intercostal tissues. Under these circumstances it is far 

 better to employ, as supports for the instrument, more 



fixed points, which must, from the nature of the chest- 

 wall, be at some distance from the centre of cardiac 

 movement. Dr. Galabin's apparatus supplies us with the 

 means needed. It is an expanded framework constructed 

 in a manner which allows of its being firmly applied to a 

 considerable expanse of the irregularly-shaped chest. 

 From the drawing its principle can be best understood 

 (See Figure). 



In the middle of the figure the sphygmograph is seen. 

 It differs from M. Marey's original in one or two minor 

 details, which are decided improvements. The most im- 

 portant of these is that the brass bar A b, on which the 



