July 5, 1883. ] 
JOURNAL OF HORTICULTURE AND COTTAGE GARDENER. 
1 
5 
Tn 
Bath (Boses) ; Eomford Show. 
Sntton (Boses). 
C 
F 
7 
S 
Chiswick Show. Crystal Palace (Boses). 
8 
SUN 
7th Sunday after Trinity. 
9 
M 
[Oxford and Wirral (Boses.) 
10 
TU 
Boyal Horticultural Society; Fruit and Floral Committees at 11 A.M. 
11 
W 
Eoyal Caledonian Society’s Show, Edinburgh ; Hull Show (3 days.) 
GARDEN CHEMISTRY. 
OT long since a professional gentleman, than 
whom no one is better able to judge, in a 
public meeting gave it as his opinion that 
nine-tenths of the agricultural community were 
ignorant of the discoveries and teachings of 
agricultural science, and especially chemistry. 
He also expressed the opinion, that were agri¬ 
cultural chemistry generally understood, our 
agriculture would at once enter upon a period of prosperity 
from which it could not easily be brought down. Truer 
words were never spoken. In spite of evil times, bad seasons, 
and crushing competition, thoroughly educated cultivators 
not only manage to live, but thrive. Many, indeed, are 
doing well under the same skies and subjected to the same 
competitive conditions that send other men, less alive to 
the importance of applying scientific facts, to the wall. 
Among farmers there is both a “ struggle for existence,” 
and also “ a survival of the fittest.” 
What is true of farmers in this respect is also true, 
perhaps to a greater extent, of gardeners. Much attention 
lias, during late years, been devoted to the physiology and 
chemistry of plants and the chemistry of soils and manures; 
but it is only here and there that we meet a gardener well 
informed enough to be able to turn any of this kind of 
knowledge they may possess to practical purposes. Yet 
there cannot be any room for doubting that a knowledge 
of such subjects would pave the way for success by explaining 
the cause of many failures, as well as acting as a guide to 
success; and it cannot be doubted that such knowledge would, 
in a majority of cases, lead to real economy, not only in 
saving, but in wise spending. 
Agriculture has a fairly good literature devoted to such 
subjects, horticulture has none worth the name. The 
energies of many eminent men in our own country, on the 
Continent, and in America, have been devoted to the dis¬ 
covery of facts in vegetable physiology and agricultural 
chemistry, with the consequence that now a* very clearly 
illumined path is before the cultivator. It is with regret 
that we have to add that in the kindred domain of horti¬ 
culture hardly anything has been done. Still the facts that 
have been discovered in agricultural chemistry are, to a 
large extent, available for gardeners; and, scattered here 
and there, for the gathering, are many facts that apply to 
the garden only. For years the writer of this has made 
garden chemistry his study, and has collected much infor¬ 
mation that he now proposes to arrange for the benefit of 
those who may choose to follow him. He believes that many 
young men are anxious to know something of the subject as 
a stepping-stone to future success, and to this class he chiefly 
addresses himself, though he ventures to believe that some 
of their elders may not peruse what he has to say in vain. 
In introducing such subjects it is usual to begin by 
saying something about soils, manures, and the physiology 
of plants first; then to go on to the elements composing 
such plants, soils, and manures, their relation and chemical 
history, and to advance step by step. This plan, when text¬ 
books are in question, is decidedly the best. But were such 
adopted in the present instance, it is feared that numbers, 
who may readily enough read papers on special subjects 
connected with the study, they might at first not be in¬ 
terested enough to wade through such details. It has, 
therefore, been decided to give papers on “ Lime and 
Liming,” “ Phosphates,” &c., to begin with, on each of 
which topics information is being continually sought, and 
which can be treated separately, though also as part of a 
whole. 
LIME AND LIMING. 
Lime exists under many different forms in the geological 
strata of the earth. Apart from limestones proper, marble, 
coral, chalk, marl, and shell sand must be regarded as 
limestones, and all used as manurial applications. All are, 
or have been, formed under water. Chalk, for instance, is 
only an agglomeration of shells not very compactly pressed 
together, as is the harder limestones, which, however, are 
only harder; and although sometimes formed, of compacted 
corals, may be seen in other cases to be composed of minute 
microscopic shells mixed with larger ones. Marble is only 
limestone vitrified by internal heat. Marls are the remains 
of fresh-water shells which have settled in inland lakes and 
in time become covered up with silt, peat, or sometimes only 
mould. Shell sands are the wrecked remains of shells in 
modern seas which are cast up on our shores. Frequently 
corals are cast up on our shore, as in Bantry Bay, and such 
are found of value as manure. 
Limestones are hardly ever pure. Being formed under 
water they generally contain sand and clay. This may 
vary from 0 up to 30 or 40 per cent. When present, 
this foreign matter detracts, of course, from the value of 
the limestone. Even in chalk much clay exists, as may be 
understood when it is remembered that the c’ay soils that 
cover the chalk in many places are but chalk remains from 
which the lime has been dissolved out and washed away by 
rain containing carbonic dioxide; but as limestones are the 
remains of minute animals, they almost invariably contain 
both sulphate and phosphate of lime. In some countries the 
sulphate is largely present, but in this it seldom amounts 
to more than four-fifths per cent., and is generally less 
in this country. In some samples, as in those from Carluke 
(Lanarkshire), phosphate of lime is present to the extent of 
1J per cent., according to Dr. Johnston. This, in the burnt 
lime, is equal to 2^ bbs. in the hundred, and adds consider¬ 
ably to the value of the lime. In the magnesian limestone 
of Durham it seldom exceeds 0-15 per cent., and is gene¬ 
rally only 0-07. In Cumberlandslaire limestone containing 
033 per cent, are found, but in other cases only the merest 
trace. Some of the limestones of the great oolite, as well as 
the Combrash and Stonefield slate, contain about 1 per cent, 
of phosphate. 
Carbonate of magnesia is almost always present. In 
even the purest limestone it amounts to 1 or 2 per cent., 
and in impure varieties from 40 to 50. Many of the beds 
in the old red sandstone contain much magnesia. Mountain 
limestone, otherwise known as dolomite, contain, when toler¬ 
ably free from clay or sand, as much as from 40 to 45 per 
cent. 
Lime containing much magnesia possesses burning or 
scorching qualities; indeed, magnesia in whatever com¬ 
bination has this quality. Yet there may be instances when 
it may be wanting in the soil, and such lime made from 
magnesian limestone may be peculiarly valuable. Such 
lime is preferred on the hill pastures of the highlands of 
Galloway, but on ordinary soil it is well not to apply such 
either liberally or extensively. A portion sparingly dressed 
will tell in a year or two whether magnesia may then be 
given with advantage. If not, it will be better to procure 
the purest lime possible, for magnesian lime cannot be 
applied with safety in quantities sufficient to such soils as 
most need liming. 
Lime is applied burnt and unburnt. Marls and chalk, 
