Contributions to the Chemistry of Chlorophyll 313 



account of the action of alkalis on chlorophyll. The conclusion he 

 arrives at is that the action induces a complete change in the chloro- 

 phyll, leading to the formation of a distinct substance which he calls 

 " chlorophyllic acid." The compounds of this substance with alkalis 

 show, when in solution, two bands in the red, one of them being very 

 thin. By the action of hydrochloric acid chlorophyllic acid under- 

 goes decomposition ; the ethereal solution of the product of decom- 

 position shows a spectrum which is, apparently, that of phyllocyanin. 



Hansen in his memoir, entitled " Der Chlorophyllfarbstoff," * 

 assumes that chlorophyll undergoes no change by the action of alkalis, 

 and even submits the crude colouring matter to a process of saponi- 

 fication in order to obtain it in a state of purity. The final product 

 obtained by Hansen appeared in spha3rorcrystals, and consisted, 

 according to him, of chlorophyll, or, as he prefers to call it, " chloro- 

 phyll-green," in the highest possible state of purity. The fact that 

 its solutions show the ordinary chlorophyll spectrum would seem to 

 prove the accuracy of this view. Nevertheless, it is evident from the 

 description of its mode of preparation and properties that chlorophyll- 

 green must have been a sodium compound ; and this, indeed, is 

 acknowledged by the author himself who, in a subsequent memoir^f 

 describes a process for obtaining the colouring matter free from 

 sodium, which, from the fact of the substance being very sensitive to 

 the influence of acids, must be conducted with care. 



In a memoir, entitled "Extraction de la Matiere Verte des Feuilles/'J 

 Guignet describes a method for obtaining the sodium compound of 

 chlorophyll in dark green, crystalline needles, of which he says that 

 its solutions show exactly the same, absorption bauds as those of 

 ordinary chlorophyll. I have repeated the experiments of Hansen 

 and Guignet, but have not succeeded in obtaining a crystalline com- 

 pound as they did, probably from want of manipulative skill on my 

 part. The product prepared by Guignet's process, though amorphous, 

 did, however, on decomposition with acid yield a result which plainly 

 showed that the body acted on was by no means unchanged chloro- 

 phyll ; the product of decomposition gave the reactions not of phyllo- 

 cyanin or phylloxanthin, but of phyllotaonin. 



In order to confirm or otherwise the results arrived at by my pre- 

 decessors, I devised a new and comparatively simple method of pre- 

 paring what has been called "alkaline chlorophyll." The process I 

 adopt may be described as follows : Fresh leaves, preferably of 

 grass, are treated with boiling spirits of wine containing about 80 per 

 cent, of alcohol. The green extract is filtered hot and, after standing 

 for a day or two, yields a dark green voluminous deposit containing 



* ' Arbeiten d. Bot. Instituis in Wurzburg,' vol. 3, p. 1. 

 f ' Arbeiten d. Bot. Institute in Wurzburg,' vol. 3, p. 3. 

 J ' Comptes Rendus,' vol. 100, p. 434. 



