AXD CHEMISTRY OF HOPS. O 



During the first year they retain their bright green colour 

 and fine, strong aromatic smell, and the Inpuline is bright 

 yellow. 



The second year they become darker, more dead-like, losing 

 their bright colour, and have a sweet, slightly cheesy odour, 

 which is di^ to the oxidation of the volatile oil, converting it 

 into valerianic acid. The lupuline is of a golden yellow colour. 



The third year the colour is not much changed, but the 

 odour becomes faint, with the same cheesy smell. The 

 lupuline is of a dark yellow or reddish tint. 



The female plant, which is the object of careful cultivation, 

 on account of its bitter and odorous strobiles employed in 

 brewing, is much richer in principles than the male plant, 

 from which it is distinguished by its aromatic, tonic, and 

 narcotic properties ; qualities which are combined in no other 

 substance. \ 



Economic Uses of Hops. The roots and the stem of this 

 plant merit also attention, as they furnish a raw material, 

 presenting the planter with a secondary useful product. 



The roots removed with the plant in the course of pluck- 

 ing, and which are generally thrown away, not only contain 

 a starchy substance, which may be converted into glucose and 

 alcohol, but also a large proportion of tannin, which the tan- 

 neries might use with advantage. This substance also offers a 

 good material for making excellent paper-pulp and cardboard. 



The stem possesses useful qualities ; vegetable wax can be 

 obtained from it, also a sap from which a durable reddish- 

 brown can be made, and its ash is used in the manufacture of 

 the Bohemian glass. Like the roots, it furnishes a very 

 solid pulp for paper and cardboard. The useful part of 



