25 



iv. Apparatus for Experiments on the Respiratory Organs. 



99. Pulmonograph, devised by Marey, for the investi- 

 gation of respiratory movements in man. 



Lent by the Biological Laboratory, Royal College of 

 Science. 1878. 



This instrument is essentially similar to the cardiograph above 

 described, except that it registers the movements of the wall 

 of the chest. 1 The apparatus passes round the chest and 

 rests firmly against the middle of the back. A knob which 

 actuates the membrane of a drum rests upon the front wall of 

 the chest, and its movements are transferred to a small drum 

 with a writing lever, precisely as in the cardiograph. 



100. Double stethograph, devised by Dr. Riegel. 

 E. 246. 1877. Made by A. Weber, Wurzburg. 



The instrument consists of a framework supporting two pads, 

 which rest one upon either side of the chest ; these are con- 

 nected with levers writing upon a strip of paper carried forward 

 by clockwork, so that the respiratory motions of the two sides 

 of the chest can be compared simultaneously. 



101. Volt's apparatus for investigating the gases given 

 off in the respiration of small animals. In glass case 

 9 ft. 7 in X 3 ft. 8 in. X 3 ft. 3 in. 



E. 247. 1877. Made by C. Stollnreuther, Munich. 



The animal under investigation is placed in the small glass 

 chamber, through which a current of air is slowly drawn by 

 means of the water-wheel. The air passes through meters, 

 which determine its quantity, and through drying tubes to 

 remove the aqueous vapour, and tubes containing potash to 

 remove the carbonic acid, by means of which the amounts of 

 these constituents are determined. 



102. Drawings (4) of apparatus for testing the products 

 of the perspiration of animals. The larger apparatus 

 is intended for the heavier quadrupeds ; the smaller 

 serves for researches on smaller mammals and birds. 



Lent by Professor Dr. Ignaz Moser, Vienna. 1876. 



This apparatus is similar in principle to No. 101. 



