tee, 
a a a 
| 
122 
the change of matter; their nitrogen appears in 
the urine, and along with it the mineral ele- 
ments previously combined with the organic 
matter, such as mercury, copper, &c. When 
such substances enter into combination with 
organised parts, the functions of those parts 
must be disturbed, and must take an abnormal 
direction, producing morbid phenomena. The 
action of corrosive sublimate and arsenious acid 
is very remarkable in this respect. It is known 
that these substances possess, in an eminent de- 
gree, the property of entering into combination 
with all parts of animal and vegetable bodies, 
rendering them at the same time insusceptible 
of decay or putrefaction; it is further known 
that the parts of a body which come in contact 
with these substances during poisoning, and 
which therefore enter into combination with 
them, do not afterwards putrefy; so that there 
can be no doubt regarding the cause of their 
poisonous qualities. It is obvious that if they 
are not prevented by the vital principle from 
entering into combination with the component 
parts of the body, and consequently from render- 
ing them incapable of decay and putrefaction, 
they must deprive the organs of the principal 
property which appertains to their vital condi- 
tion, viz., that of suffering and effecting trans- 
formations; or, in other words, organic life must 
be destroyed. If the poisoning is merely super- 
ficial, and the quantity of the poison so small 
that only individual parts of the body capable of 
being regenerated have entered into combination 
with it, then eschars are produced—a pheno- 
menon of a secondary kind—the compounds of 
the dead tissues with the poison being thrown 
off by the healthy parts.” [Liebig’s Chemist hy 
of Agriculture and Physiology. | 
Many salts are constituents of soils and of 
manures, and play an essential and highly im- 
portant part in the nutrition of plants. Some 
are the sole ingredients in special manures; some 
are invariable and mighty ingredients in organic 
manures; not a few occur or are formed in all 
fertile soils; and many, either in themselves, or 
in their bases, or acids, or elements, or recom- 
binations, contribute the whole or very nearly 
the whole of the inorganic principles or incom- 
bustible parts both of wild plants and of cul- 
tivated crops. Some, such as the carbonate of 
ammonia, the carbonate of lime, the sulphate of 
lime, the nitrate of soda, the nitrate of potash, 
the phosphate of lime, and the phosphate of mag- 
nesia, perform offices within the soil and in vege- 
tation which constitute the main difference be- 
tween barrenness and activity; and some, such 
as several of those just named and also the sili- 
cate of potash, the carbonate of potash, the car- 
bonate of soda, the carbonate of magnesia, the 
oxalate of potash, the oxalate of lime, the malate 
of potash, the malate of lime, and many more 
are essential constituents of many of the most 
valuable or best known plants of either the gar- 
ne hen ad at lt pl cee nt 
SALT. 
cn eh an nme 
den, the field, or the wilderness. The carbonate 
of lime, for example, occurs in pease, vetches, 
wheat, barley, timber trees, and many other 
plants; the carbonate of magnesia is often as- 
sociated in plants with the carbonate of lime; 
the sulphate of lime occurs in small quantities 
in clover, lucern, sainfoin, turnips, and potatoes ; 
the nitrate of soda occurs in barley; the nitrate 
of potash, in woad, horse-radish, sunflower, and 
common nettle; the phosphates, in the seeds of 
the cereal grasses and of the sarcolobous legumes; | 
the silicate of potash, in the culms of grasses; 
the carbonate of potash, in potatoes and in many 
shrubs and timber trees; the carbonate of soda, 
in fuci, salsolas, and most land- plants which 
grow near the sea; the oxalate of potash, in sorrel 
and some fuci; the oxalate of lime, in rhubarb, 
parsley, spinach, squills, fennel, and tormentil ; 
the malate of potash, in rue, madder, nasturtium, 
lilac, and garden purslane; and the malate of 
lime, in wake-robin, houseleek, and mignionette. 
Some salts, also, occur in the roots, some in the 
stem, some in the leaves, and some in the seeds 
of the same plant; and several or even many 
sometimes occur, in a common association, either 
throughout an entire plant or throughout some 
of its parts. For example, no fewer than fifteen 
salts, besides some binary salt-like bodies, have 
been found in two of the most common fuci of 
the British shores,—the sulphate of potash, the 
oxalate of potash, the silicate of potash, the hy- 
driodate of potash, the malate of potash, the 
muriate of potash, the carbonate of potash, the 
sulphate of soda, the carbonate of soda, the 
muriate of soda, the sulphate of magnesia, the 
muriate of magnesia, the phosphate of magnesia, 
the oxalate of lime, and the phosphate of lime. 
The multiplicity and importance of the range of 
saline action in the way of supplying direct nu- 
triment to vegetables may be sufficiently inferred 
from our articles Manure and Foop or Puants; 
the width and power and diversity of that action, 
in the way of preparatory or digestive transmu- 
tation of substances for the service of vegetation, 
may be partly conjectured from our articles Ma- 
NURE, ALKALIES, Lime, AMMoniA, and NITRATES; 
and the particular action or actions of some 
of the most important salts, or of their con- 
stituent principles, either directly or indirectly 
or by recombination, may be learned from our 
articles Manure, ALKALIES, ALUMINA, Acips, Sopa, 
PorasH, Lime, CHALK, Gypsum, Ammonia, Mac- 
NESIA, CARBONATES, NitRATES, PHOSPHATES, SILI- 
ca, and AsHEs. 
Many salts perform the whole of their fer- 
tilizing action, and others perform a main or 
considerable part of it, by undergoing decom- 
position, and letting loose their bases and their 
acids, to work out results independently of each 
other, and according to their respective nature ; 
and in not a few instances, they set up a recipro- 
cating process between decompositions and re- 
combinations within the soil and decompositions 
