124 Report of Schimmel § Co. 1922. 



Hofmann concludes from his observations that most of the odoriferous substances 

 act not only on a single, but on various peripheric receptive organs of different 

 specific energy. Whenever a series of such receptive organs are acted upon and 

 act together, combination smells are generated and the individual smells disappear 

 more or less. The author considers this phenomenon to be the reason why some 

 aromatics, when concentrated, show an odour different from that in diluted state 1 ). 

 By taking for granted that an odoriferous substances acts on several receptive organs 

 it might be readily explained why the odours of many chemically pure substances 

 resemble each other, and why from newly-synthesised bodies specific new odours 

 result which otherwise are not to be found in Nature. 



In a paper entitled, TJber einen historischen Beitrag zur Theorie der Geruchsempfindung 

 (On a historical contribution towards the theory of odour perception), H. Heller 2 ) cites 

 and discusses a passage from a book published, in 1814, by C.W. G. Kastner, professor 

 of physics and chemistry in Halle, and entitled, Einleitung in die neuere Chemie (Intro- 

 duction into modern chemistry). The author proves that already more than one hundred 

 years ago Kastner held views on perception of odour which highly resemble modern 

 theories. Nowadays, we agree with Kastner that the senses of taste and of smell are 

 in close relation to each other, and also that in both cases it is necessary for the 

 actual sensation that the respective active body be virtually present. Likewise, Kastner's 

 opinion is correct insofar that we are only able to smell gases. We are unable to. 

 perceive liquid aromatics by their smell in case they are introduced into the nose. 

 In Kastner's opinion, sensation of odour is due to a disturbance of equilibrium. This, 

 too, is correct. On the mucous membrane of the nose, the content of water in the 

 membrane and in the surrounding air, under normal conditions, are in equilibrium; 

 however, as soon as the inhaled air carries particles of an aromatic, the conditions 

 of osmotic and the chemical equilibrium are upset which makes the basis of sensual 

 perception 3 ). Finally, Kastner maintains that the sensation caused on the nasal mucous 

 membrane is more unequivocal and less subject to errors than the sensation of sight. 

 Heller agrees with this view (hitherto not contradicted) and supports it by proofs, the 

 discussion of which, however, would carry us beyond the scope of our Report. 



The same author 4 ) demonstrates by various instances that chemical compounds 

 which are generally said to show an offensive or unpleasant odour, when in a quite 

 pure state, cause an entirely different and often even pleasant sensation of smell, 

 sometimes, too, none at all. Pure acetylene, pure carbon disulphide, whose impurities 

 show a putrid smell, show a pleasant ethereal odour. Likewise, various alkyl sulphides 

 (isoamyl, ethyl sulphides), even ethyl mercaptane may be freed nearly entirely from 

 their unpleasant smell by heating with copper powder (decomposition being but feeble); 

 the latter adsorbs the evil smell. Hydrogen arsenide, whose garlic-like smell could 

 be hitherto regarded as characteristic for that body, is according to Thorns and Hess 5 ) 

 odourless when quite pure, and when applied to the tongue causes a feeble sweet 

 taste. (Of course these experiments were carried out with infinitesimal quantities.) 



Heller points out that these facts have not received due consideration in some 

 recent investigations, e. g., in those of Kauffmann and of Henning on odour sensations. 

 Hence, Kauffmann's 6 ) theory of the change of odour (with alkylamines, mercaptanes, 





x ) Cfr. the view held by Tschirch, preceding abstract. — 2 ) Deutsche Parfiim.-Ztg. 7 (1921), 83. — 

 3 ) Cf. for this the above-cited paper by Tschirch. — *) Deutsche Parfiim.-Ztg. 1 (1921), 123. — B ) Ber. d. 

 dentsch. pharm. Gas. 30 (1920), 488. — «) Ztschr. f. Psychologie, 2. AM. 1908, 217. 



