( 11' ) 



The olfactometric measurements showed: 



1. thai the volatilised muscon adheres strongly to the glass walls 

 along which ii passes. 



2. that rubbing such a ulass wall with cotton wool »ïves rise, 

 instead of an odour of muscon, to a smell, reminding of muse. 



This smell of muse was also noticed with niass wool, cotton wool. 

 feathers or paper, placed in the path, but not with asbestos wool 

 and platinum sponge, the time of exposition in all these cases having 

 been about 1 / t minute. 



This led to a closer investigation, which I undertook the more 

 readily, since an investigation by «1. Aitkkn in 1905 showed that 

 the odorous principle of muse must be regarded as a gas 1 ). Thus 

 the above-mentioned olfactometric cylinder, containing 0,627 % 

 muscon in nivristic acid anil having a length of 10 cm. and a 

 diameter of 0.8 cm., was connected by means of a short brass piece 

 with equally long and wide tubes of all sorts of material, in such 

 a way that these tubes could, if required, be kept at a predetermined 

 temperature by a water-jacket. The thus formed canal passed into 

 an aerodromometer 2 ), i.e. a vertical glass tube in which an aluminium 

 disc is suspended between two spiral springs, the displacement of 

 which indicates the velocity of the air-current by means of an 

 empirical scale. After the aerodromometer finally followed a large tin 

 cone in which an electrically driven fan maintained a suction from 

 the narrow towards the wide end. The connection between the 

 different pieces could be removed and re-established in a moment. 



The air, passing through this system, went successively through: 



1. the olfactometric cylinder over its full length of 10 cm. 



2. the tube of which the adsorption is to be examined. 



3. the aerodromometer. 



In the experiments here mentioned the velocity of the air-current 

 was perfectly constant; 84 cm.' passed per second. Each exposition 

 lasted accurately 5 minutes. Between the experiments the olfactometric 



lumen, i.e. "> cM 2 cross-section). Gf. on this point Physiol, des Geruchs, Leipzig 

 1895, p. 185. The significance of this coefficient, which rises and falls with the 

 smelling power of a substance, is at once seen, when one recognises the close 



d 



relation between it and the quantity b in Fechner s celebrated formula 7 = k log 



b 



(Psychophysik II, p. 13;. It deserves notice that the odorimetric coefficient of 



muscon in liquid paraffine is zero. 



') J. Aitken. Evaporation of musk and other odorous substances. Proc. Roy. Soc. 

 Vol. 25, p. 894, 1905. 



a ) H. Zwaakoemaker. Arch, f. Anat. u. Physiol. (Physiol Abth.). 1902, p. 417. 



