COUNTRY VILLAS. 



163 



summer; and thus to prevent the sand from 



being carried along the drain, and in a few 



years choking it up. Once a year, the 



grating at top is taken off, and the deposit 



of sand taken out with a spade having a 



kneed bUide; and by this means not only 



may the drains be kept quite clear and 



effective for many years, but much smaller 



and less expensive drains may be made at 



first. Where the subsoil is sandy, gravelly, 



or rocky, and where it is not considered 



essential to use the walks immediatel)' after 



rain, drains of the box or barrel kind may be dispensed with, and common 



rubble drains formed by filling up a trench with round stones, to within a 



few inches of the surface, as mjig. 79., and terminating 



it by a somewhat coarser portion of the common gravel 



used in forming the walk, through which the water 



will percolate, throughout the whole length of the 



drain. In flower-gardens, and indeed in extensive 



shrubberies, brick traps of the kind described above 



may be dispensed with, and the bell-trap represented 



in fig. 73., or some other trap of the kind, may be 



made use of; but, in this case, these traps must be 



cleaned out after every shower of rain. 



252. Drainage map, — In all extensive establishments, and even in small 

 ones, where the drainage is in any degree intricate, it is desirable to have a 

 map exclusively devoted to the under-drains, which should be accurately laid 

 down on it, and accompanied by sections and dimensions, taken in different 

 parts of the course of the drains, and projected on the plan alongside of the 

 points where they were taken. Every successive addition and alteration sliould 

 be introduced in the plan when made, and accompanied by the date. The 

 use of such a plan is twofold: 1. to show the precise situation of the drains 

 already existing, when any new drain is to be made ; and, 2., as a guide when 

 any drain becomes stopped up, and the point of stoppage is uncertain. By 

 penetrating into the suspected drains at different distances, though only with 

 a boring augei', or even in some cases with a crowbar, an immense deal of 

 labour may be saved in detecting the seat of the evil ; especially in cases 

 where the principal servants have been changed since the drains were last 

 opened. 



253. The pleusiire-groiinds, in places of only two or three acres in extent, 

 may generally be considered as including the whole of the grounds, with the 

 exception of the space occupied by the house and offices, and by the kitchen- 

 garden. The number and the direction of the walks through this space will 

 depend on various circumstances, but chiefly on the taste of the family for 

 flowers and shrubs, and the annual expense which they are willing to incur 

 in keeping the grounds in order. In general, the walks should be so far apart, 

 or so hidden or disguised by undulations of the surface or by planting, that 

 more than one walk shall never be seen at a time. In irregular surfaces, 

 therefore, it is obvious that the walks may be much more numerous tlian in 

 such as are even or flat ; and, in surfaces richly varied by groups of t;ees or 



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