130 Report of Schimmel 8* Co. 1922. 



Chemical Notes. 



In a paper entitled, "Some constituents of essential oils and their structural 

 relations", J. W. D. Hackh 1 ) endeavours to give an outline of the structural relation of 

 the above-mentioned constituents, and to illustrate by practical application the advantages 

 of structure symbols, the new chemical notation of organic compounds, the present 

 method of notation occupying a vastly greater space and annoying the printer in a 

 high degree. The old formulae are replaced by geometrical devices which eliminate 

 the customary symbols C, H, 6, N and represent their atoms by points from which 

 one, two, three, or four lines, respectively radiate. A straight line^— stards for hydrogen 

 (H— H, assuming one atom of hydrogen at either and of the stretch), an angle > 



represents water (u/O), the sign — < stands for ammonia (H— N\h)> and a cross -f~, 



H 



for methane I H— C— H I . Where two stretches meet, one atom of oxygen is located, 



(H-C-H I 



where three or four meet, an atom of nitrogen, or carbon, respectively^ Each organic 

 compound belongs to a different type and a different class, such as hydrocarbons 

 (o— , or R— H, the circle standing for the radical), alcohols (o—y, or R— OH), aldehydes 

 (o-/?, or R— CHO), §c. The type of the compound indicates its chemical character and 

 reactivity, the class its general structural characteristics, either saturated or unsaturated, 

 aliphatic or aromatic. Expressed by the new notation, ~\ — (- stands for ethane CH 3 — CH 3 , 



)<Z>> for ethylene CH 2 =CH 2 , I | for hexamethylene C 6 Hi 2 , (| for benzene 



C 6 H 6 , j J for menthane, and |++| for camphor, 8jc. 



+++ + 



These examples seem sufficient to give the reader an idea of Hackh's notation. 

 Those who are interested in the study of the new system may resort to the original 

 paper, where the notation of 157 compounds occurring in essential oils is given and 

 their structural relation is detailed. 



The salts of the higher fatty acids, when in solution, crystallise in the shape of 

 a spongy mass which, according to C. A. Cofman-Nicoresti 2 ), shows a great power for 

 absorbing volatile oils. As little as 5 per cent, of the salts was sufficient for obtaining 

 such "solid solutions". 



Hydrocarbons. 



A process for obtaining aromatic hydrocarbons has been devised by A. S. Ramage 3 ): — 

 Hydrocarbons containing one or more alkyl groups are treated, in the presence of a catalyst, 

 such as ferrous oxide, with hydrogen. The alkyl groups are hereby replaced by hydrogen. 



A process for the preparation of polycyclic hydrocarbons of the terpene series, for 

 which a patent is applied by the firm of Schering, of Berlin 4 ) consists in heating the 



*) Journ. Amer. pharm. Ass. 9 (1920), 948. As per a separate copy kindly forwarded to us. — 2 ) Chemist 

 and Druggist 95 (1921), 854. — 3 ) Am. Pat. 1365849 of Jan. 18 th , 1921. As per Chem. Zentralbl. 1921, II. 558. 

 - *) Germ. Pat. Appl. C/29518, published Jan. 12™, 1922. 



