218 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 
Lime is a constituent of all plants ; its function is connected 
with the building up of the tissues and the formation of cell- 
walls. It is not only a direct plant-food, but is one of the most 
effective manures, and should be studied from many points of 
view. 
(a) Lime acts upon the various ingredients contained in soils. 
It changes those that are inert into plant- foods, and destroys the 
bad qualities of the ingredients that are prejudicial to plants. It 
gives fertility to boggy peats, or organic soils, by neutralising the 
injurious organic acids present in the soil. Therefore lime acts 
as an excellent antidote for " sour " land. 
(b) By decomposing organic matter, lime hastens the process 
of nitrification. 
(c) Lime improves the physical nature of the soil, and has a 
tendency to promote a healthy growth of plants. 
(d) In the working of clay lands lime is very valuable. 
Besides converting insoluble compounds into soluble ones, it 
renders such lands more friable, and thereby facilitates cultiva- 
tion. 
(e) It has also beneficial effect upon sandy soils of a light 
nature. It renders them less porous, therefore better able to 
resist the parching action of the sun's heat during a hot, dry 
summer. Lime also helps to retain moisture in light sandy 
soils. 
Mode of ajojylying Lime. 
On cultivated land, and old gardens in which there is a large 
quantity of humus, a heavy dressing of unslaked lime should 
be applied in order to produce the necessary degree of fermenta- 
tion ; whilst on shallow lands having a few inches of soil only 
a light dressing, occasionally repeated, appears to be the better 
method. The benefit to be derived from lime greatly depends 
upon the nature and condition of the soil. Most lands are much 
improved for two or three crops by lime, but frequent repetition 
will often not have the same good effect. 
A proportion of from three, six, to nine tons of lime per acre 
may be regarded as light, medium, and heavy dressings. 
Gas -Lime. 
Limo is used in the purification of coal-gas. The residue, 
after the purification, is known as gas-lime. It is a mixture of 
