November 1, 1883. ] 
JOURNAL OF HORTICULTURE AND COTTAGE GARDENER. 
377 
% 
mnd has settled in the second tub, run it off with an im¬ 
provised syphon made out of gas pipe or other suitable tube. 
1 en dry both deposits separately in an oven hot enough to 
■dissipate all moisture, but not to bake the soil. What settles 
a once is sand, what does not settle for some time is agri- 
cu tmal ciay. If no more of this clay be present than 
' soil would be called sandy soil; if from 
_ to 4J it would be sandy loam; if from 40 to GO it would 
be loam; if from 60 to 80 clayey or heavy loam, and over 
oU clay. 
But soils are not wholly composed of sand and clay. Some 
contain much stony matter, and are called gravel; some contain 
inardry any mineral matter and are called peat. Besides, these 
soils contain a lesser amount of other matters, such as lime, 
potash, phosphates, ammonia, humus, Ac. To illustrate this, 
perhaps a couple of tables will show my meaning better than any 
yei aal description. Clay and sand are merely mechanical matters, 
ime and ammonia are plant-foods. Thus, though sand, clay, or 
peat may form over 90 percent, of the whole, yet the mineral 
matters named as entering into the composition of plants are, 
amatively, of much more importance. 
The substances usually found in fertile soils are— 
r 
mechanical constituents 
plant-food 
Soil 
organic 
'■inorganic 
constituents capable of 
yielding plant-food 
( sand 
1 clay 
(stones 
(ammonia 
j nitrates 
f phosphorus 
| sulphur 
I potash 
I lime 
! magnesia 
“1 silica 
soda 
chlorine 
iron 
(. manganese 
( humus 
organic matter other 
than humus 
undecomposed mine¬ 
rals. 
This table shows that soils are composed of, first, mechanical 
■constituents, and also plant-food prepared and in preparation. 
I will now give an analysis of a fertile soil from the Carse of 
Gowrie by the late. Professor Anderson of Glasgow, to show that 
even in a very fertile soil plant-food forms a small proportion of 
the whole. 
Soil. 
Subsoil. 
Silica . 
6M954 
61-6358 
Peroxide of iron. 
4-8700 
6 2803 
Alumina . 
14-0400 
14-2470 
Lime. 
0-8300 
1-2756 
Magnesia. 
1-0200 
1-3938 
Potash . 
2-8001 
2-1761 
Sulphuric acid. 
0-0911 
0 0396 
Phosphoric acid. 
0-2400 
0-2680 
Chlorine . 
0-0098 
0-0200 
Organic matter . 
8-5508 
6-8270 
Water. 
2-7000 
4-5750 
96-5472 
93 6882 
The part played by the plant-food is elsewhere noticed, but 
this is the proper place to say something of the properties of the 
different mechanical constituents in soil. 
In gardening language clay gives “ body ” to soil, and when it 
is absent sods are generally barren. In chemical language clay 
is an aluminic silicate, and, as we have seen, has its origin in the 
■eruptive rocks, such as granite and whinstone. It is rarely that 
pure clay occurs, and in fertile soils it very generally contains 
potash, often in large quantities, as well as other mineral foods 
for plants. 
If we take liquid manure, in which soluble phosphates, 
■ammonia salts, &c., are dissolved, and filter the solution through 
a potful of loam, it will be found that the water leaves the phos¬ 
phates, ammonia, potash, Ac., behind. The clay in the loam has 
daken them out of the water, and will keep them in its grasp till 
used by the plants, at least in the case of the mineral matters ; 
for, as we have seen, the ammonia becomes changed to nitrates, 
which clay cannot keep. Pure sand cannot do this. If such 
solutions be run through pure sand it will be found that very 
little of the manure is left behind. Besides fixing manurial 
■matter, clay absorbs and retains water. Sand, from which what 
we call superiluous water is allowed to drip, will often contain 
no more than 5 per cent, of water. Clay, on the other hand, 
will hold as much as 50, and yet be apparently dry. Then clay, 
by reason of its superior attraction for water, will remain moist 
because of the water which it attracts from the subsoil in dry 
weather when sands are parching dry. Again, of the moisture 
which sand really does retain when rain falls, most of it evaporates 
very readily. Olay soils do not thus lose theirs so readily. 
Then sand, of all soil ingredients, least possesses the power of 
absorbing moisture from the air. Clay has a great attraction 
for air-moisture. While sand will, if pure, hardly take in any 
of the moisture which condenses as dew on cool nights, which 
so often succeed hot drying days, clay will absorb a very sensible 
amount. 
Sand, however, is not useless. Pure clay is so adhesive and 
retains so much water, especially in wet seasons, as to be un¬ 
workable. Sand opens them and allows the water to percolate. 
In very heavy soils, which become pasty mud in wet weather 
and compact masses in dry, roots cannot travel either to fix the 
plants or to find food. When sand is present, on the other hand, 
roots run easily, and find the food the clay holds. Because of 
their wetness clay soils are cold. When sand is present this 
wetness can be cured by draining, and so the soil is made warmer. 
While, then, sand on the one hand, and clay on the other, form 
neither of them desirable soils, a mixture of them—loam—without 
the objections of either, combines the virtues of both. But in 
choosing a loam for potting or border-making purposes, some 
care is necessary in order to avoid being deceived. It not un¬ 
commonly happens that in river bottoms, and even in hollows by 
the side of mountain streams, particularly when in Hood, the flats 
are inundated, that what is apparently a medium loam, and is 
called by that name, is no loam, contains no clay, but is medium 
in texture because composed of very fine, what old experienced 
gardeners term dead,” sand. This is about the most objection¬ 
able soil that could be chosen, as it too frequently is. Poor and 
incapable of being enriched, it is also solid, impenetrable, and 
no sand, no grit can open it. The particles clog up everything, 
barring the way of either roots or air. 
Sand when seen through the microscope is composed of round 
polished stone, mostly pure quartz. Gravel, as we wish to be 
understood in our use of the term, is only larger sand, and, though 
capable of trituration, resists weathering and chemical action 
with some obstinacy. But in addition to rounded quartz stones 
(small as sand, large as gravel), much gritty matter exists as 
sandy stony matter, not only capable of being easily disinte¬ 
rgated, but of yielding considerable quantities of plant-food. In 
the case of soils derived from such rocks as trap this is often very 
considerable. The acids generated by decaying vegetation, the 
salts, such as common salts so generally present in rain near the 
sea, and often applied in manure as sulphate of ammonia, 
nitrate of soda, Ac., coupled with the digestive power of roots, 
have a wonderful effect in preparing for plant-food those potas- 
sic silicates, calcic carbonates, Ac., which the disintegrating 
action of frosts and cultivation expose to their action. Not 
only, therefore, are stones mechanical agents in soils, retaining 
moisture as they do and keeping the soil open, but as we have 
named them in conjunction with vegetable remains, not plant- 
food, but capable of yielding it. Stones represent so much 
money value, even though not larger than what constitutes fine 
sand. They are partially disintegrated but not decomposed 
minerals. 
Though iron must be regarded as plant-food, and its 
presence, therefore, a necessity in all soils, it frequently 
happens that as the red oxide it is too plentifully present. No 
better way of finding out whether this is the case or not exists 
than just examining the water. In clear water it imparts the 
well-known taste that the palate can detect. But such water 
will not run in a stream far, nor stand long exposed to the air 
without showing a red deposit. But springs of no great depth 
may show iron while the upper soil is healthily free from it. 
Sand that has long lain dry, even though the subsoil may be red 
or black with iron, is often first-class every way. It is when, 
in wet weather, the water stands on the surface where the land 
is low and undrained, or when apt to be flooded with iron-im- 
piregnated water, that too much iron is to be feared. But even 
such iron-impregnated soils might be of use for mixing with 
others singularly deficient in it. It is said that iron helps the 
colour of many flowers, Roses included. Possibly a little irony 
loam might be of use for such. In many cases iron causes the 
formation of impenetrable pans in the subsoil. How to deal with 
them will be noticed under another heading.— Single-handed. 
FORCING LILY OF THE VALLEY. 
The Lily of the Valley is one of the most generally esteemed 
flowers in cultivation, and on this account the supply of its 
beautiful and sweetly scented sprays of flowers cannot be 
obtained too soon, nor seldom in quantity sufficient to meet 
