Physiology. — “On Smelling during complete Exhaustion (resp. 
adaptation) for a given odour.” By K. Komuro (Nagasaki). 
(Communicated by Prof. H. ZWAARDEMAKER.) 
(Communicated at the meeting of March 26, 1921). 
A rather considerable number of qualities (so-called specific ener- 
gies) is to be distinguished in the sense of smell. This is borne out 
by exhaustion-experiments performed long ago by FROHLICH, ARON- 
SOHN, ZWAARDEMAKER, HERMANIDES. 
FrOuHLIcH') first fatigued his olfactory organ by a given odorous 
substance and then tried to find out whether this organ was still 
sensitive to other smells. In his discourse he wrote: “Wenn z. B. 
Valeriana Celtica gerochen wurde, so wurde darauf der so nahe 
stehende Geruch von Patchouli nicht wahrgenommen; wohl aber 
erregte Valeriana nach Patchouli noch einen sehr lebhaften EKindruck.”’ 
ARONSOHN’) has made a more careful study of the subject. He 
used some phials filled with different odorous substances. He kept 
smelling at them until his sense-organ had absolutely been blunted 
for the scent. Then he took another phial and tried to smell its 
odour, if possible, and he determined its intensity. 
By their intensity he groups the odorous substances into three 
classes, viz. 1°. those of insistent intensity; 2°. those of decreased 
intensity, and 3°. those that become inodorous. When e.g. his sense- 
organ was exhausted for the tincture of iodine, it was still fully 
sensitive to the stimulus of ethereal oils and also ether; only faintly 
so to that of oil of citron, of sage, of nutmeg-blossom, of turpentine, 
of bergamot and of cloves. Nothing was smelled, however, of balsam 
of copaiba and of spiritus. Some more exhaustion-experiments were 
made for sulphammonium, camhpor and oleum juniperi. He describes 
his result as follows: ‘‘Verschiedene Geruchsqualitäten afficiren ver- 
schiedene Bezirke der Geruchsnerven derart, dass eine Classe von 
Riechstoffen einen Bezirk maximal erregt, einen zweiten Bezirk in 
niederen Grade, einen dritten gar nicht erregt.” 
Similar experiments have been performed by ZwAsaRDEMAKER*) in 
1) FROHLICH, E. Sitzungsber. d. Kaiserl. Akad. d. Wissensch. Wien. Bd. 
Vins. 2322. 
*) ARONSOHN, E. Archiv. f. Anat. u. Physiol. 1886. S. 361. 
3) ZWAARDEMAKER, H. Die Physiologie des Geruchs. Leipzig. Engelmann. 
S. 255. 1895. 
