Contributions to the Chemistry of Chlorophyll. 303 



evaporated. During evaporation it deposits an amorphous red powder, 

 which is filtered off and washed with a little cold alcohol. This red 

 powder is a zinc compound ; when burnt it leaves a residue of zinc oxide. 

 On being treated with hot alcohol to which a little hydrochloric 

 acid is added the powder dissolves, yielding a crimson solution, which 

 after adding water and shaking up with ether divides into two layers, 

 an upper brown ethereal one and a lower one which is acid and has a 

 bright crimson colour. The two liquids having been separated, the 

 upper one is found to leave on evaporation a brown amorphous 

 residue, while the lower one, after partial evaporation, gives with 

 water a brown precipitate. The latter, having been filtered off, is 

 dissolved in boiling alcohol ; the alcoholic solution deposits on stand- 

 ing fine lustrous crystalline needles. 



The properties of the substance prepared as just described are as 

 follows : In mass it appears plum-coloured, and shows much lustre. 

 Under the microscope it is seen to consist of small, regular, prismatic 

 crystals, which are reddish-brown by transmitted light. Heated on 

 platinum it melts to a brown mass, which on being further heated 

 burns, leaving much charcoal. When heated in a tube it gives off 

 fumes, but yields no crystalline sublimate. It is soluble in boiling 

 alcohol and ether, the solution having a red colour inclining io 

 crimson. It is also soluble in chloroform, but insoluble in carbon di- 

 sulphide even on boiling. It dissolves in glacial acetic acid and in 

 concentrated hydrochloric acid, the solutions exhibiting a fine crimson 

 colour. The solutions show well-defined absorption bands, but their 

 spectra differ inter se ; those of the alcoholic and ethereal solutions 

 are nearly, alike, but that of the solution in hydrochloric acid is very 

 different. The spectra are remarkable for the entire absence of bands 

 at the red end, but they need not be further described, as they are 

 represented on the plate accompanying this paper. 



I give no name to this substance, as it may possibly turn out to be 

 identical with one or other of the bodies obtained by Hoppe-Seyler 

 as products of the action of caustic potash on his chlorophyllan,* one 

 of which he has named "dichromatic acid," while to another he 

 applies the term " phylloporphyrin." I may state that the spectrum 

 of the hydrochloric acid solution of my substance corresponds exactly 

 with that of a purple-coloured solution (containing unfortunately 

 very little substance) labelled " phylloporphyrin," which I owe to the 

 kindness of Dr. Schuchardt, of Goerlitz. The yield of my substance in 

 relation to the quantity of phyllocyanin employed is exceedingly small, 

 as the account of my method of preparing and purifying it would, 

 indeed, lead one to conclude. Large quantities of one or more other 

 substances are formed at the same time, but, being brown, amorphous, 

 and humus-like, they do not invite examination. 



* ' Zeits. f . Phjsiol. Chem.,' vol. 4, Heft 3. 



