KAHLENBERG — ACTION OP SOLUTIONS ON TASTE. 23 



duce this bitter taste, which is characteristic of all potassium salts, 

 it is clearly to be ascribed to the potassium ions. The mobility 

 of potassium ions is about one and one-half that of sodium ions so 

 that their diffusion is more rapid. The taste of potassium ions 

 being fairly pronounced, it is not as readily masked as that of so- 

 dium ions. Thus it is possible to distinguish solutions of KC1 

 from NaCl and KI from Xal; the iodine ion not having as 

 strong a salty taste as the chlorine ion, the difference in taste be- 

 tween the potassium and sodium ions comes out fairly distinctly 

 in dilute solutions of the last named salts. Sulfate of potassium 

 solutions have the characteristic bitter, disagreeable taste of the 

 potassium ions; these solutions lack the sharp taste of the N0 3 

 ions, which we have in strong solutions of KN0 3 and other ni- 

 trates when these are applied to the tip of the tongue. Solu- 

 tions of KC10 3 do not have the salty taste of the chlorine ions. 

 The bitter taste of the potassium ion is somewhat masked by 

 the effect of the C10 3 ion, the latter acts especially on the tip 

 and edges of the tongue creating its own characteristic sharp 

 taste. Solutions of XaBr0 3 were incidentally tested in this 

 connection; they have but a slight taste which is not salty. The 

 Br0 3 ion has a taste similar to that of the C10 3 ion, which would 

 naturally be expected. The tip of the tongue is quite suscep- 

 tible to irritation by various salts, many of them giving that 

 peculiar sharp or burning sensation, which is different from the 

 taste of hydrogen ions; thus, KI, Nal, NaCl, NH 4 C1, etc., 

 besides the nitrates when applied in strong solutions on the very 

 tip of the tongue cause a burning sensation, which they do not 

 produce on other parts of the organ. 



Lithium ions appear to have but little taste. A •£ solu- 

 tions of Li N"0 3 was very difficult to detect by taste ; £% gave 

 a rather alkaline smooth impression, and -fa a sharp taste like 

 a solution of jSTaK0 3 of equivalent concentration. This 

 sharp taste is probably due to the action of the nitrate on 

 the tip of the tongue and is to be ascribed to the action of the 

 N0 3 ion. The mobility of the lithium ion is only a little over 

 one half that of the potassium ion, hence its diffusion is slower, 



