242 JOURNAL Of THE ROYAL HORTICULTURAL SOCIETY. 
All these tests at best, however, merely afford rough indications 
and give but little idea of the extent of the deficiency. If an accurate 
estimation is required, the only known means is a chemical estimation 
by analysis. In view of the fact that within our own islands the lime 
contents of the soil may vary from 60 per cent, to *i per cent, (or one 
tenth of 1 per cent.), it will seem that an accurate determination is 
essential. As Hall says in his well-known book on manures : — " Every 
farmer should find out by analysis the amount of lime in the soil, 
as the whole scheme of manuring should depend upon it." 
The Table shows the extraordinary variations in the lime content 
of different soils taken from various parts of the country. 
Lime Content of Various Soils. 
No. 
Per cent, of Free Lime 
as Carbonate 
Remarks 
I 
2-0 
Soil in high state of fertility. 
2 
•273 
Hereford — soil sour — wanted draining — responds 
to lime. 
3 
I.38 
•6 9 
Worcester — hop soil. 
4 
Pershore — intensive cultivation. 
5 
45'77 
North Kent — fruit soil. 
6 
•678 
Worcester — old pasture. 
7 
•345 
Romney Marsh soil. 
8 
6.9 
East Kent — good potato soil. 
9 
•805 
Average Guernsey soil. 
10 
i-86 
Kent. 
11 
•48 
Middlesex — market-garden ground — infested 
with club-root. 
12 
2-68 
Middlesex — market-garden ground — no club — 
very healthy crops. 
Some difference of opinion exists as to the percentage of lime 
that should be present in the soil, and it is impossible to fix any definite 
limits, but it is probably accurate to say that, at all events in the case 
of highly -manured soils, -5 per cent, is the lowest limit and is necessary 
for the health of vegetation, and to get the best results it should not 
be less than 2 per cent., but this largely depends on the fine state of 
division in which the lime is present. 
When it has been proved by one or more of the above tests that 
the soil is deficient in lime, the next considerations are, first, the type 
of lime to use, and, secondly, the method of application. With regard 
to the first point, it is obvious that the ground carbonate, owing to 
the simple method of production, is considerably cheaper than any 
of the forms of caustic lime, and it will therefore be more economical 
to use it when either form will give equally good results. 
It has been proved that in acid soils, as long as there is absolute 
acidity to counteract, carbonate of lime is as effective in neutralizing 
the acidity as the more expensive caustic form. On peaty soils, there- 
fore, and sour pastures, and all soils that give a definite acid reaction, 
carbonate should be used. On soils very rich in humus, as most old 
garden soils are, carbonate will be the more economical, as the intense 
chemical activity of the caustic form will result on such soils in a loss 
