1904 



Journal of Applied Microscopy 



GENERAL PHYSIOLOGY. 



RAYMOND PEARL, University of Michigan. 



Books and Papers for Review should be Sent to Raymond Pearl, Zoological Laboratory, 

 University of Michigan, Ann Arbor, Mich. 



Veress, E. Beitrage zur Kenntniss der Topo- 

 graphic der Warme-Empfindlichkeit. Arch. 

 f. d. ges. Physiol. 89 : i-S6. Taf. I-VI, 1902. 



This very extensive and thorough study 

 of the relative sensitivity of different 

 regions of the human body for warmth 

 is of value both for its new results and on account of its contribution to the 

 technique of the subject. The thermaesthesiometer used in the experiments is 



shown in section in Fig. 1. It consists 

 of a metal cylinder 10 cm. long and 4 

 cm. in diameter, open above and below. 

 Internally it is partially divided into two 

 unequal parts by the metal plate a. 

 From each of these two compartments 

 a short tube extends, through which 

 warm water may flow in and out respect- 

 ively. The lower end of the cylinder is 

 connected with a truncated cone, which 

 ends finally in the end-piece d bearing 

 the stimulating surface e which has a 

 diameter of G mm. Through a cork in 

 the upper end of the cylinder is passed 

 thermometer h graduated to J^ Centi- 

 grade degrees. The bulb of this ther- 

 mometer lies just over the plate e. The 

 purpose of the partition a is to cause a 

 constant flow of the hot water directly 

 over e. When the apparatus was to be 

 used its inlet tube was connected by rub- 

 ber tubing with an " Hugerschoff s port- 

 able water heater," the water supply to 

 which could be controlled by a screw cock, 

 and warm water was allowed to run through. The temperature in the thermaes- 

 thesiometer may be controlled by varying the rate of flow of water through the 

 heater, and also by varying the height of the gas flame which furnishes the heat. 

 When the thermometer registered 38-40° C. (approximately the temperature at 

 which the sensation of warmth is first felt) the surface c was laid lightly on that 

 portion of the surface of the body whose sensibility it was desired to test. The 

 thermometer reading at the moment when the sensation of warmth was first felt 

 was recorded, and then the temi^erature of the thermcesthesiometer was rapidly 

 raised until this sensation gave place to a definite feeling of pain. The temper- 



FlG. 1. 



