SINAPIS ALBA. 
7 
medicinal purposes, and as a young salad herb. In some counties 
it is so common in many corn fields as to become as troublesome a 
weed as the arvensis, or charluck, and for which it is not unfre- 
quently mistaken. It may however be distinguished from the latter, 
by the leaves of the former being more jagged, and from the 
Sinapis Nigra, by the stalks of the former being finely grooved and 
strongly haired. This annual plant flowers in June ; and rises with 
a branched hairy stalk, two feet in height ; the flowers grow in loose 
terminal spikes • the blossoms stand on horizontal foot stalks, com- 
posed of four yellow petals ; stamina six, greenish ; anthers yellow, 
upright, and somewhat arrow shaped; germen inversely ovate, slightly 
angular, (hispid when magnified) stile tapering and two-edged ; 
stigma obtuse ; glands four; calyx perianthium, four-leaved, spread- 
ing, deciduous; leaves petioled, alternate, and mostly pinnated, 
slightly hirsute on both sides, composed of three or four pair of 
pinnae, lowermost one very small, terminal one often three-lobed, 
and all of them variously indented. 
Properties. Mustard seed has but little smell ; taste warm 
and pungent, and somewhat bitter; the sifted powder is more 
pungent than the bruised seeds : an essential oil is obtained by 
distillation, heavier than water, excessively pungent and penetrating. 
The oil obtained from the seeds by expression, retains none of the 
acrid or pungent principles; it being bland and insipid, but soon 
grows rank by keeping. An infusion of the seeds has a warm, 
pungent, acrid, and somewhat sweet taste ; colour pale and opaline ; 
it is not changed by sulphate of iron. Alcohol extracts less of the 
pungent principle than water. The Sinapis Nigra, contains more of 
the pungent principle than i\m Sinapis Alba ; the former is cultivated 
in large quantities, for manufacturing the flour of mustard ; which 
has been long in general use as a condiment. 
The flour of mustard, like most other articles of general con- 
sumption, is frequently adulterated; its pungency is increased by 
the addition of Cayenne peppier ; and its price reduced by salt, and 
rye or pea flour. The cake remaining from the hulls, when the oil 
is expressed, is more pungent than the whole seeds, this when 
ground has been long in use for reducing ground pepper; and 
known by the dealers, under the name of P. D. (i. e. pepper-dust). 
Medical Properties an o Uses.* The general eflfects of 
* The medicinal properties of the black and while mustard are the same, although 
the latter is generally preferred for internal tisg. 
