12 EULLETIN OF THE UNIVERSITY OF WISCONSIN. 



gentleman, were about sixty and sixty-three years old respec- 

 tively. All were in excellent health and were practically total 

 abstainers from the use of intoxicating liquors and tobacco. 



The solutions, which were prepared with distilled water that 

 was practically tasteless, contained chemically equivalent quan- 

 tities, i. e., they were so-called normal solutions. I chose the 

 solutions of such strength that they would give me distinct im- 

 pressions of taste, not sufficiently strong, however, to produce 

 in any case lasting disagreeable or painful sensations. A por- 

 tion of each of these solutions was then diluted with water to 

 one-half its former strength; a portion of each of the solutions 

 thus obtained was again diluted with water to one-half its 

 strength, and so on until a solution was obtained, the taste of 

 which I could not distinguish from distilled water. About 

 200 cc of each dilution was prepared. The solutions were kept 

 in flasks thoroughly cleaned and steamed; they were labeled in 

 cipher known only to me. This w T as done because many of the- 

 persons tested were conversant with eheim'cal symbols, and it 

 was my purpose to have them entirely ignorant of the contents 

 of the solutions they were tasting, so that they would report the 

 sensations they received without being biased by thoughts as to 

 how the solution ought to taste. The chemicals used were of 

 the chemically pure kind of reliable makers. The distilled 

 water was ahvays used as a check. 



The subject was first given an opportunity to thoroughly rinse 

 the mouth with distilled water so as to remove any excess of 

 mucous. Seated with his back toward the table on which were 

 the flasks containing the solutions, the subject took from a por- 

 celain spoon about four cubic centimeters of the solution to be 

 tasted. The individual held this in the mouth for a few mo- 

 ments, being permitted to move the tongue and lips at will so 

 as to spread the liquid over the entire cavity of the mouth, and 

 bring the liquid into more immediate contact with the mem- 

 branes by friction. The solution was then ejected, the report 

 given, and the mouth generally rinsed with a little distilled water 



