> a hn 
a A 
| gon Porrifolius. 
_ genous, biennial, herbaceous plant, of the goat’s- 
a BSA sn SAS 
SALSAFY. 
exotic plants, of the acanthaceous order. The 
scarlet species, S. coccinea, was introduced a few 
years ago from Jamaica to the stoves of Britain ; 
and is a low branching shrub, of very great 
beauty. Its leaves are opposite, peduncled, and 
ovate; and its flowers grow in loose, graceful, 
axillary, and terminal spikes, and stand out from 
them in opposite pairs, and have a tubular shape 
with expanding margin, and are scarlet without 
and white within, and bloom in autumn and 
the early part of winter. 
SAL PRUNELLE. See Nirrarzs. 
SALSAFY, or Sausiry,—botanically Tragopo- 
An ornamental, culinary, indi- 
beard genus, and of the succory division of the 
composite order. It grows wild in the moist 
meadows of some parts of England; and has long 
been cultivated in kitchen gardens. Its roots 
are long, white, and fleshy ; its stems are smooth, 
tender, and about 4 feet high; its leaves are 
_ leek-like and comparatively broad; its calyx is 
| longer than the florets or floral rays; and its 
_ flowers have a dull purple colour, and bloom in 
_ May and June. Its roots have a mild and sweet- 
_ ish flavour, and are boiled and eaten like ear- 
rots; and its young shoots are dressed and used 
in the manner of asparagus. It loves an open 
situation, and a deep soil of rich mould; and 
may be raised from seed sown at any time from 
March till May, either broadcast in beds, or in 
small drills 8 or 10 inches apart. The young 
plants, when 2 or 3 inches high, must be thinned 
out to distances of 6 inches; and the beds or 
drills must be occasionally watered. The roots 
will be fit for gathering from August till Octo- 
ber; and the young shoots, in the following 
spring. 
SALSILLA, See Liny (Earasie Roorep). 
SALSOLA. See Saurworrt. 
SALT. This term was originally employed to 
denote common salt, but was afterwards gen- 
eralized by chemists, and employed by them in 
a very extensive and not very definite sense. 
They understood by it any body which is sapid, 
easily melted, soluble in water, and not com- 
bustible; or a class of substances midway be- 
tween earths and water. Many disputes arose 
concerning what bodies ought to be compre- 
hended under the designation, and what ought 
to be excluded. Acids and alkalies were allowed 
by all to be salts; but the difficulty was, to de- 
termine respecting earths and metals; for several 
of the earths possess all the properties which have 
been ascribed to salts, and the metals are capa- 
ble of entering into combinations which possess 
saline properties. The old chemists, however, 
eventually restricted the term salt to three class- 
es of bodies,—acids, alkalies, and the compounds 
which acids form with alkalies, earths, and me- 
tallic oxides, The salts of the first and second 
of these classes were called simple salts; and 
these of the third class were called compound or 
SALT. 
neutral. This last appellation originated from an 
opinion long entertained by chemists, that acids 
and alkalies, of which the salts are composed, 
were of a contrary nature, and that they coun- 
teracted one another ;. so that the resulting com- 
pounds possessed the properties neither of acids 
nor of alkalies, but properties intermediate be- 
tween the two. The chemists of a later period 
restricted the term sali still more, by tacitly ex- 
cluding acids and alkalies from the class of salts 
altogether; and the definition of it then came 
to be,—a definite compound of an acid and a 
base, each comprising at least two elementary 
substances ; and though this definition excludes 
the whole group of what are called haloid-salts, 
and does not accord with the theories of some 
of the principal modern chemists, it is still, and 
perhaps will long continue, the most convenient 
for all popular and practical purposes. 
The acid constituent of a salt may possess 
any degree of sourness, from an absolute nega- 
tion of it up to the most mighty corrosive- 
ness; and the basic constituent may be either 
an alkali, an alkaline earth, or a metallic oxide. 
Some salts, such as Epsom salt and Glauber’s 
salt or sulphate of magnesia and sulphate of soda, 
are readily recognised by all persons as true salts; 
but others, such as marble, gypsum, bone earth, 
and flint glass, or carbonate of lime, sulphate of 
lime, phosphate of lime, and the double bisilicate 
of potash and bisilicate of lead, are thought by 
untutored observers to be totally different from 
salts. Yet the constitution of the latter is formed 
on exactly the same type as the former; bone 
earth, for example, being a compound of the cor- 
rosive oxygen acid of phosphorus and the earthy 
alkaline oxide of calcium, just as Epsom salt is 
a compound of the corrosive oxygen acid of sul- 
phur and the earthy alkaline oxide of magne- 
sium. Haloid salts, on the other hand, possess a 
truly salt-like appearance, but differ widely from 
all true salts in constitution ; they comprise all 
the metallic chlorides, iodides, and fluorides, and 
are closely akin in nature to the oxides and the 
sulphurets; and they take for their type, the 
chloride of sodium or common salt, which con- 
sists merely of the two elements chlorine and so- 
dium, and whose Greek name, together with a word 
signifying ‘ form,’ furnishes the epithet haloid. 
The new theory regards common salt as the 
type, not only of the haloid salts, but of all salts 
whatever; it views common salt as formed by 
the metal sodium taking the place of the hydro- 
gen of hydrochloric acid; it supposes every acid 
to be ultimately or really a hydrogen one, and 
every salt of each acid to be formed by a metal 
taking the place of its hydrogen; and in order 
to make out its data, it ascribes all the oxygen 
of saline compounds to their acids, and denies 
that any of these acids are hydrates. In the 
case of the alkaline and the earthy sulphates, for 
example, it affirms that they contain, not the 
alkalies and the oxides themselves, but only their 
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