946 SEC. 18. BIOLOGY. 



3759. Sphygmodynamometer, an apparatus for estimating 

 the blood pressure in the radial artery of man. 



Dr. C. Friedldnder, Strassburg. 



The apparatus is made for determining the variations of the blood pressure 

 in the radial artery in man ; e.g., the diurnal variations, the changes which 

 the blood pressure suffers under the influence of poisons and various physio- 

 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, Brcslau. 



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 traces 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 neuer 

 Sphygmograph und neue Beobachtungen an den Pulscurven der liadialarterie 

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

 Verlagsbuchhandlung (Adolf Kiepert). 



3761. RiegePs Double Stethograph. Weber, Wurzburg. 



3762. Sphygmograph. Weber, Wurzburg. 



628. Portable Pneumatic Apparatus. 



Prof. Dr. Weldunburg, Berlin. 



This apparatus serves for condensing and rarefying air for medico-therapeu- 

 tical and physiological purposes. It is possible by its means 



1. To inspire during its use compressed air whose degree of compression 



remains constant, but the compression of which can be varied to any 

 extent by means of a known weight lying on it. 



2. To exhale into rarefied air whose rarefaction is known and can be varied 



by means of the superimposed weight. 



3. To inspire rarefied air. 



These three methods of action not only produce a certain mechanical effect 

 on the organs of respiration, but also affect the heart and the circulation. The 

 apparatus is therefore adapted for studying the physiological action of com- 

 pressed and rarefied air on the circulation and respiration. 



Its principal applications, however, are to medico-therapeutical objects, for 

 which its mechanical action renders it applicable ; as, 1, the inhalation of 

 compressed air ; 2, exhalation into rarefied air ; and, 3, inhalation of rare- 

 fied air. As a remedy it is suitable for a series of lung and heart diseases ; as, 

 for example, the exhalation into a rarefied atmosphere has been ascertained 

 to be beneficial in many cases of emphysema of the lungs and asthma. 

 The inhalation of compressed air in the treatment of pleuritis, bronchitis, 

 phthisis, &c. 



