VI. CIRCULATION AND RESPIRATION. 947 



3763. Fneumatometer. Prof. Dr. Weldunburg, Berlin. 



This instrument consists of a manometer, one limb of Avhich 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 pneumatoineter 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. Several may be put into action, either singly or together. An 

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

 Two other similar signal apparatus serve in connexion with two differently con- 

 structed electric double keys for marking the beginning or end of the electric 

 shocks, or other effects. The rapidity of the movement of the blackened 

 paper is variable within Avide limits. 



3765. Apparatus for Artificial Inspiration and Ex- 

 piration. Physiological Institution, Prague. 



Two pumps working synchronously, one of which is devoted to inspiration, 

 the other to expiration. The number and depth of the respiratory acts are 

 variable within wide limits. The apparatus allows also the employment of 

 mixtures of gases and the preservation of the air expired without loss. 



3766. Portable Injection Apparatus, with constant pres- 

 sure, for artificially filling the blood and lymph vessels. 



Physiological Institution, Prague. 



By means of this apparatus every pressure between 2 and 300 mm. of 

 mercury can be produced, and it remains unaltered during the whole con- 

 tinuance of the injection. The apparatus may be used for the simultaneous 

 injection of two groups of vessels. 



3767. Scheme of the Circulation. 



Physiological Institution, Prague. 



The apparatus consists of two glass cylinders, communicating by a horizontal 

 tube, one representing the arterial, the other the venous, system. In the 

 horizontal tube there is, in imitation of the capillary system, a sponge, in 

 which the resistance to the current may be diminished or increased at will 

 by means of a screw. A small pump brings the fluid with the desired force, 

 or in the desired quantity, from the venous into the arterial system. 



302 



