OTHER INDISPENSABLE CONDITIONS. 293 



in moisture. From the surface of warm damp soil water is 

 perpetually escaping in the form of invisible vapour; if the 

 soil is freely exposed, that vapour is dispersed as fast as it is 

 formed ; but when it is confined beneath a beU-glass the air is 

 unchanged, and the vapour remains in a state of suspension, 

 bathing and invigorating the whole surface of the cuttings. 

 When this is well managed, the whole of the injurious effects of 

 sun-light are prevented, and all the advantages of it secured. 



But it is not sufficient to place cuttings under a beU-glass 

 with a moist soil and a due supply of bottom-heat. Two other 

 things must be considered : the one is, to preserve the external 

 air in a uniform state ; the other is, to take care that the soil 

 is not too wet. 



If the air on the outside of bell-glasses is not as warm as 

 that beneath them, or warmer, the moisture floating in their 

 interior will condense on the sides of the glass and run down, 

 by which means the air that surrounds the cuttings will 

 fluctuate as to the quantity of water it holds suspended ; and if 

 the external air is much colder than the internal, will, in fact, 

 be dry, instead of damp. In their delicate state tender cuttings 

 will not bear this ; it is of the utmost consequence to them that 

 all the conditions to which they are exposed, except light, 

 should be perfectly steady. 



The condition of the soil as to water is also of infinite! 

 importance. If it is wet, cuttings are apt to rot ; if dry, they I 

 are sure to fade. "When a cutting is placed in a wet medium, it 

 may attract more water than it can digest; in that case its 

 fluids will become putrid, and its solid fabric must decay. It 

 is therefore indispensable, in all delicate operations, that the 

 soil should be of such a nature as to be incapable of holding 

 much water between its particles; and hence the value of silver 

 sand, the most favourable of aU the materials within a gardener's 

 reach. Nevertheless, there are some hard-wooded plants which 

 will not only bear an excess of water, but are the better for it. 

 We have seen the common Ghent Azaleas struck by placing a 

 cutting of the young wood, with a heel to it, in a bottle of water, 

 inclosed within a large Ward's Case, none of the leaves having 

 been removed. In such plants as the Azalea, however, it is to 



