— 104 — 



these animals had received hypodermic injections of menthol dissolved 

 in olive oil, a linked menthol compound appears, possibly menthol 

 glucuronic acid. 



Since R. Kobert and E. Levy's experiments had shown that 

 camphocarbonic acid and its esters are physiologically absolutely in- 

 operative, the same scientists 1 ) have also examined some acetyl deriv- 

 atives of camphor for their action on the animal organism. It was 

 then found that oxymethylene camphor behaves like camphocarbonic 

 acid, and has no camphor-action whatever. 



Its bactericide properties are also very slightly developed. Oxy- 

 ethylidene- and oxypropylidene camphors, however, very much resemble 

 laurus camphor, in their physiological action. R. Gottlieb observed 

 on rabbits, after hypodermic injection of the ethylidene compound, 

 a specially rapid and powerful spastic effect. The propylidene com- 

 pound is also a spasm-producing toxin, though less powerful in its 

 action. 



Camphor mono- and di- iodide have been tested for their phy- 

 siological behaviour by Messrs. E. Merck. The former has no decided 

 antiseptic properties, and only irritates sensitive mucosa. It does not 

 give rise to camphor-symptoms. It is non-toxic. Camphor di-iodide 

 is a more powerful irritant than camphor iodide. It has a caustic 

 action on the mucous membrane of the skin and of the stomach. 

 It may possibly be found useful in cases where, in addition to an 

 irritating effect, an absorbing action is desired, for instance in all 

 chronic eczemata and similar affections. 



Physiology of the sense of smell. 



H. Zwaardemaker publishes some interesting treatises on the 

 physiology of the sense of smell. Before entering into details, the 

 olfacto -physiological measuring apparatus (olfactometer) and the unit of 

 measure (olfactia) are described. The olfactometer 2 ) consists essentially 

 of a smelling cylinder (magazine cylinder), and a tube through which 

 the smelling takes place. The magazine cylinder is pushed either 

 completely or only partly over the tube, according to the requirements 

 of the test, and by these means the limits of excitement and of 

 perception are ascertained, that is to say, the position in which an 

 undefined or a qualitative olfactory sensation occurs. In an olfacto- 

 meter, whose magazine cylinder consists of india-rubber, there occurs 

 for example, for a normal organ of smell, an olfactory sensation, when 

 0,7 cm. of the india-rubber cylinder is not covered by the inner tube. 



*) loc. cit. 



2 ) H. Zwaardemaker, The physiology of the sense of smell, Leipzig 1895. 



