KANSAS ACADEMY OF SCIENCE. 



some of the mixed excitations of these assumed nerves of smell must be outside of 

 our experience, and consequently the corresponding sensations do not exist, and 

 they would probably be found wanting even if by any artificial means the mixed ex- 

 citement in question could be produced. Considering the discreteness of the chem- 

 ical properties of compounds, it seems questionable whether a number of specific 

 end organs could, by each responding more or less to the action of different com- 

 pounds, give mixed excitements characteristic of these compounds. 



Hence it seems that the sensations of smell must form a discrete manifoldness 

 in any case, and it seems also that there must be a large number of specific groups 

 of olfactory nerves, each corresponding to a characteristic odor forming an element 

 of the above manifoldness, though probably each characteristic odor may be tbe 

 nucleus of a limited region of continuity. 



The existence of a large number of specific nerve groups is not without example 

 among the several senses. For the auditory apparatus comprehends as many as 

 sixteen to twenty thousand specific elements, each with an end organ adapted to the 

 disturbing influence of a particular case of external stimulus. However, in any case 

 the arrangement of a large number of specific end organs so as to prevent confu- 

 sion is a difficult problem (remembering that the strongest argument in a case like 

 the present is to show the possibility). Histology, indeed, recognizes but one type 

 of end organ in the regio olfactoria, but we must remember that the character of the 

 external stimuli active in the sense of smell requires the distinctive feature of these 

 end organs to depend upon molecular structure, so that the microscope cannot dis- 

 tinguish between them. On the other hand, the character of the external stimuli of 

 sound requires form to be the distinctive feature of the specific end organs of hear- 

 ing. The present usefulness of the sense of smell to man scarcely seems to warrant 

 the existence of a highly-organized apparatus of smell, yet there can be no doubt 

 but that there may have been a period in our development when this sense was 

 vastly more important. Indeed, there are indications of the degeneration of this 

 sense in man. 



All the experimental results in this field, although perfectly powerless in the di- 

 rection in which the investigators have attempted to apply them, viz., toward the 

 establishment of a systematic arrangement of odors, are cumulative evidence of the 

 discontinuous nature of the sensations of smell, and of the existence of a large num- 

 ber of independent (nearly) groups of specific olfactory nerves. 



Then, too, the fact that contrast effects are not known in odors as they are in 

 colors, and the fact that fatigue for one odor leaves the sense delicate for another, 

 both partake of the nature of positive evidence in this direction. If the large 

 amount of patient and careful research in this field had been applied as evidence of 

 this view of the subject, it might not have been so entirely fruitless, although it is 

 difficult to see how positive evidence in this direction is to be reached, at least until 

 histology is able to attack molecular structure, and chemistry has cleared away the 

 mist still hanging over the nature of the "odorous particles." 



NOTES ON MAGNETIC DECLINATION IN KANSAS. 



BY PROF. F. 0. MARVIN, STATE UNIVERSITY, LAWRENCE. 



By Kansas law, each county surveyor in the State is required to observe the decli- 

 nation of the magnetic needle four times in each year — in the months of January, 

 April, July, and October — and to report the results to the office of the Secretary of 

 State and to the Chancellor of the University. No compensation is fixed for the 



