18 THE GBAPE. 



It was probably a mistake which led Crasso in an 

 earlier examination which he made of vine branches 

 of one and two years standing, with respect to the 

 ash constituents, to imagine that he found more 

 lime than potash.* 



The tables above given are of importance, both as 

 exhibiting the respective proportions of the compo- 

 nent parts named, and also in connexion with the 

 previous summary of the incombustible constituents 

 of the vine. In the first place, we see what appears 

 remarkable, that soda, which constitutes a large por- 

 tion of the ashes of the wood, diminishes considerably 

 in every part of the fruit, and is entirely wanting in 

 the stones; whereas the potash plainly increases in 

 quantity, though to a less degree, in the skins than 

 in the juice, so that two-thirds of the ashes consist 

 of potash. 



In Nos. 2, 3, and 4, we have the analyses of the un- 

 fermented grape juice, and I wish to direct attention 

 particularly to it. We find in it oxides of iron and 

 manganese, which pass partially into the wine, also a 

 a large quantity of phosphoric acid, which belongs to 

 the albuminous substances of the grape juice, silicic 

 acid, sulphuric acid, chloride of lime, magnesia, and a 

 small proportion of soda, and sodium, combined with 

 chloride, as muriate of soda. 



In the juice of the unripe grape, Nos. 1 and 2, and 

 in the constituents of the ash, we perceive no remark - 



* Ann. Bd. 57, s. 67. 



