416 Mr Gustav Mann on the 



Methods employed by different Observers to Extract 

 THEIR Pure Chlorophyll. 



I here add a list of the different methods employed for 

 the extraction of what each writer considers pure chloro- 

 phyll. The methods mentioned are those of Gautier, 

 Hansen, Hoppe-Seyler, A. Meyer, Pringsheim, Sachsse, 

 Schunk, and Tschirch ; along with Detmer's method of 

 preparing a crude chlorophyll extract. 



Detmer's Method of 'preyaritig a Crude Chlorophyll Extract.^ 



Young wheat plants or Elodca canadensis are boiled for 

 a quarter to half an hour in distilled water. The water is 

 then poured off, and the plants are washed in water, and 

 extracted with strong alcohol. To quicken the process, the 

 alcohol may be warmed. 



Gautier's Method.f 



1. Green leaves are triturated with sodium carbonate and 

 alcohol, and the green alcoholic product is treated with 

 animal charcoal, which takes up the colouring-matter and 

 leaves the impurities behind. 



2. The charcoal is extracted with alcohol, which removes 

 a yellow colouring-matter. 



3. Next, the charcoal on treatment with common ether or 

 petrol ether should give a green solution, which, on evapora- 

 tion, allows the green colouring-matter to crystallise out. A. 

 Hansen repeated the process, but was unable to get the 

 same results, the charcoal not giving up the colouring-matter 

 on treatment with ether or petroleum ether. 



Er Adolph Hansen's Method of preparing " Chlorophyll-green. 



»+ 



The material used is grass, because it contains no resins, 

 tannin, turpenes, &c. 



1, Boil a quantity of grass to get rid of soluble substances 

 and yellow and brown colouring-matters, which on evapora- 

 tion form a brown extract. 



* Das Pflanzen physiologische Practicum. 



+ Comptcs Rendus, Ixxxix. 861. 



+ Arhcitcn d. But. InditiUs in TVilrzhurg, iii. 123, 430. 



