58 SMELL, TASTE, ALLIED SENSES 



the organ of smell in an air-inhabiting vertebrate is 

 continued for some time, it is said to result ultimately 

 in the destruction of the olfactory hairs. Thus Schultze 

 (1862) noted that when the olfactory membrane of an air- 

 inhabiting amphibian is flooded with water, the cilia with 

 which it is provided may continue to beat for hours, 

 but the much longer and heavier olfactory hairs vanish 

 almost at once. To minimize this deleterious effect Aron- 

 sohn, therefore, introduced into the nose material dis- 

 solved, not in ordinary water, but in physiological salt 

 solution and at an appropriate temperature. With these 

 precautions he claimed that it was very easy to recognize 

 weak solutions of clove oil. Vaschide in 1901 confirmed 

 Aronsohn's results and pointed out that temperature 

 was a more important factor in carrying out conclusive 

 tests than the composition of the solvent. 



These results, which were in direct opposition to those 

 of Weber, were criticized by Zwaardemaker (1895) and 

 especially by Veress (1903) who showed that the pro- 

 cedure employed by Aronsohn probably resulted in a 

 failure to fill the olfactory cleft. Veress maintained that 

 unless great care was taken at this step, air was very 

 likely to remain in this cleft and thus the solution that 

 was being tested would never really reach the olfactory 

 terminals. Under such circumstances odorous particles 

 would escape from the solution into the air filling the cleft 

 and thus reach the olfactory organ as in ordinary olfac- 

 tion. Thus it became necessary in making a conclusive 

 test to take steps to insure the complete filling of the 

 olfactory cleft with the solution to be tested. After 

 some experimentation on the human cadaver, Veress per- 

 fected a technique whereby this could be accomplished. 



