Chemical examination of the Hop. 307 
See re ae REDE ee eee 
ewrmiractive metic, 5 isc es 2st os he AO 
mbiited DRinciple, |i: 5, aw +, eid 4) oc wri we RES 
Me Bs ies ie ta og 4 sk 2 gua ag Sg 
Resin, . . ai oikcshi pe 
_A woody fibrous substance, or Lignin, .... 46 
‘ep. 12.—Two drachms of the leaves,* from which all 
the lupulin had been separated, were digested twelve hours 
in six ounces of boiling water. The infusion was bitter, 
and exceedingly unpleasant to the taste ; it possessed none 
of the aromatic flavour and peculiar bitter of the lupulin. 
When filtered and evaporated, it yielded five grains of nau- 
seous extract. ‘The same leaves were again digested in six 
ounces of proof spirit: after twelve hours, the infusion was 
filtrated, and, by evaporation, yielded five grains of extract, 
similar to the last. ‘The same leaves were digested twenty- 
four hours in alcohol ; the infusions manifested none of the 
grain , 
ter obtained from the leaves was sufficiently characteristic of 
the hop to designate that it was obtained from that article.} 
From this, and other similar experiments, leading to the 
Same results, I think it is conclusively proved, that the vir- 
tue of the hop resides exclusively in the lupulin; that the 
leaves contain a nauseous extractive matter, which is im- 
parted to water and to alcohol, and which, instead of adding 
to the bitter and aromatic fiavor of the lupulin, partially 
neutralizes or destroys it. 
e obvious inference from these results was, that the 
lupulin was the only part of the hop essential to economi- 
cal purposes; an inference so little anticipated, that it be- 
Came an important subject of enquiry, whether that part of 
the plant was duly estimated by practical brewers—wheth- 
er it had been regarded by authors as preferable to the 
leaves, and if so, what impediment or what consideration 
Prevented its being separated from the chaff. 
*It will be understood that by the leaves are meant the calices which form. 
