26 



v. Apparatus for Experiments in the Digestive Organs. 



103. Kronecker's incubator, with diffusion apparatus 

 for experiments in artificial digestion. 



Made by Warmbrilnn, Quilitz, $ Co., Berlin. 

 E. 175. 1877. 



The outside metal cylinder is filled with water, and by 

 means of a gas jet and regulator kept constantly at any desired 

 temperature ; it may be emptied by a stop-cock. Within the 

 metal is a glass cylinder, which fits into the centre of the latter 

 and rises up through its lid. From its lower end a glass tube 

 passes out horizontally through the metal cylinder arid ends in 

 a glass stop -cock. The funnel contains a filter of parchment 

 paper, through which the products of digestion diffuse. The 

 upper portion of the glass serves as a kind of Mariotte's bottle 

 for constantly washing away the products of digestion. 



104. Bunsen's filtering pump, by Desaga, Heidelberg. 



Lent by the Biological Laboratory, Royal College of 

 Science. '1878. 



In this apparatus suction is produced by water flowing drop 

 by drop into a tube of such a diameter that the drops com- 

 pletely close it. The tube is connected with the interior of a 

 flask, through the cork of which passes the neck of a funnel 

 containing the liquid to be filtered. The air is carried down 

 between the drops of water, and if a long tube be used a 

 considerable pressure can be obtained. 



vi. Apparatus for Experiments on the Sensory Organs. 



105. A set of five resonance globes with case of 

 tuning forks. 



Lent by the Biological Laboratory, Royal College of 

 Science. 1878. 



Each globe is of such a size that it will resound to a -note 

 of a particular pitch, and hence permit it to be identified when 

 sounded along with others. In this way the harmonics or 

 over- tones of a compound note may be recognised. 



106. Phakoscope for determining the changes in the 

 form of the human crystalline lens during accommoda- 

 tion, designed by Professor Helmholtz. Made by Sittel, 

 Heidelberg. 



Lent by the Biological Laboratory, Royal College of Science. 

 1878. 



