KAIILENBERG — ACTION OF SOLUTION'S ON TASTE. 13 



before another solution was tasted. I had the person sit with 

 Ins back toward the table on which the flasks stood, for I found 

 it necessary that, in order to get from liini an unbiased report, 

 he should not know from which flask I was giving' him. In test- 

 ing as to the relative strength of the taste of several solutions, I 

 could thus give the same solution twice in succession or give 

 simply distilled water without the subject's knowledge. I found 

 that this procedure was quite necessary in many eases in order 

 to obtain reliable results. The distilled water and the solutions 

 were of the same temperature, about 23° C. As my purpose 

 was rather to compare the tastes of different solutions than to 

 find out in each case as accurately as possible the moat dilute 

 solution that could still be tasted, I did not deem it necessary to 

 raise the temperature of the liquids to that of the body. 



Each person experimented upon was not detained more than 

 half an hour at a time, and the solutions were always given be- 

 ginning with the weaker and proceeding to the stronger. This 

 was very essential, for preliminary experiments indicated that 

 when a strong solution is first given the effect of it is apt to re- 

 main in the mouth and make other tests difficult for the time 

 being or perhaps even impossible. For the same reason, too, 

 all strong solutions that would be apt to leave a prolonged taste 

 in the mouth were either entirely avoided, or given the subject 

 as the last solution to be tested at that sitting. The solutions 

 used were in all cases perfectly odorless unless otherwise stated. 



The Taste of Solutions of Electrolytes. 



The taste of solutions of electrolytes received attention, first, 

 because these solutions have in many cases very pronounced 

 tastes that render work with them relatively easy; furthermore, 

 when I first began the experiments, it was simply my purpose 

 to investigate the taste of the ions; as the work progressed it 

 took a somewhat wider scope, nevertheless most of the experi- 

 ments were conducted with solutions of electrolytes. 



Sour Taste. As pointed out above the sour taste of acids is 



