VI. CIRCULATION AND RESPIRATION. 799 



logical and pathological conditions. Thus the apparatus is actually intended 

 for purposes different from those of the sphygmographs which have been 

 hitherto described, but it can also be used as a sphygmograph. A descrip- 

 tion of it will shortly be published in a physiological journal. 



3760. New Sphygmograph (Sommerbrodt's). 



Dr. Sommerbrodt, Breslau. 



This sphygmograph transfers the movements of the wall of the blood 

 vessel to a point moving up and down vertically by means of a one-armed 

 weighted lever, and has a contrivance for fixing, which excludes, especially 

 in researches on the radial artery, any vibration of the apparatus. 



The performance of this apparatus in relation to the already known 

 characteristics of the pulse curves surpasses in a striking way that of Marey's 

 sphygmograph, which has hitherto been universally used, and which depends 

 on the action of a spring. Besides, it has been possible, with the help of this 

 apparatus, to make a series of new observations on the pulse curves given by 

 the radial artery, and to discover some completely new features which it 

 presents. The details of these observations are given in a paper published in 

 March of the present year, which bears the following title : " Ein newer 

 Sphygmograph und neue Beobachtungen an den Pulscurven der Radialarterie 

 von Dr. Julius Sommerbrodt. Privatdocent, Breslau. A. Gorschorsky's 

 Verlagsbuchhandlung (Adolf Kiepert). 



3761. Riegel's Double Stethograph. Weber, Wiirzburg. 



The double stethograph as well as the sphygmograph may be used and 

 experimented with a " clinique " under careful direction. As a guide to the 

 stethograph, Dr. Riegel's treatise to " Die Athembewegungen " is added. It 

 can be purchased, bound, for 9 marks. The double stethograph described in 

 it is indeed of less recent construction, and is much dearer, but substantially 

 the description answers perfectly. 



3762. Sphygmograph. Weber, Wiirzburg . 



3763. Pneumatometer. Dr. W^aldenburg, Berlin. 



This instrument c onsists of a manometer, one limb of which is connected 

 by means of a tube with a mask for the face. It is used for measuring the 

 force of inspiration and the force of expiration in healthy and diseased indi- 

 viduals. In persons who suffer from diseases of the organs of respiration, the 

 instrument not only gives the measure of the strength of inhalation and exha- 

 lation as such, but especially records the relative proportion in which each 

 function is modified, so that in certain diseases the force of inhalation is 

 principally or entirely affected ; in others, the force of exhalation ; and in others 

 finally, both are affected. In this way the pneumatometer serves as a new 

 physical expedient for the diagnosis of disease. 



3764. Kymographion, for the registration of the pressure of 

 the blood and of the respiratory movements on a blackened surface 

 of 250 centimetres long and 23 centimetres high, which may be 

 changed for another within half a minute. 



Physiological Institution, Prague. 



Accessory apparatus are used for the blackening and for fixing on the 

 black. Two quicksilver manometers, one spring manometer, and a drum 

 recorder. Many may be put into action, either singly or together. An 

 electro-magnetic signal apparatus marks every single and every fifth second. 



