276 RED COLOUR OF LEAF 



be no doubt that green tea is manufactured at a 

 higher temperature than black. But in China 

 Paochong tea, which is a black tea, is submitted 

 for a few seconds to the red-heat of iron. Thus 

 it is obvious that the difference and apparent 

 blackness of colour of black tea must depend on 

 other causes than high or low temperature, or any 

 management of heat. 



This able chemist proceeds to state, that a sub- 

 stance which he describes and terms "Apothem " 

 is obtained from " Extractive." It is found in 

 black tea, but not in green ; and it is this product 

 which gives the colouring matter, and red or brown 

 infusion to black tea. He further adds, that it is 

 not the product of analysis, but is due to manipu- 

 lation and high temperature : also that the proper- 

 ties of the extractive of black and green teas are 

 different. (lb. p. 639.) 



But the red or brown colouring matter of black 

 tea, and the red infusion, have been shown to arise 

 from a particular treatment of the leaves by expo- 

 sure to sun and air, like hay (To Ching), previously 

 to roasting ; and that corresponding results have 

 been produced by exposure to sun, without the 

 action of fire. (P. 148. §§ 1 & 6.) 



Again, so far from the black, brown and red 

 appearance of the dried leaves being the effect of 

 high temperature, even a moderate degree of heat, 

 if more than the aqueous condition of the leaves 

 can bear, has the effect of turning them pallid and 



