872 THE COMPLETE GRAZIER. BOOK ix. 



becomes choked altogether, and destroys the drains. Now, if a sub- 

 stantial stone or brick-built mouth, in the form of a very short culvert, 

 were in all cases put round the farthest out-tile, a little valve provided, 

 and its exact position and everything else described in a book kept for 

 the purpose, it could scarcely be lost sight of, except under the 

 grossest mismanagement. Care should also be taken, in every 

 instance in which the ground at all permits of it, to give a drop of 

 9 or 12 inches from the sole of the outmost tile to the bottom of the 

 open ditch." 



As to the cost of draining operations, much need not be said, as this 

 will depend upon a variety of local circumstances ; consequently the 

 results of experience at one place will be no guide to the probable results 

 at another. " The principal circumstances," says Mr. Spooner, " which 

 determine the cost of drainage works are : The labour of cutting and 

 filling the drains, the material of which the drain itself is formed, and 

 the outlets for the discharge of water. Of these, the last increases 

 in proportion as the ground is steep and irregular or unusually flat, 

 and can only be included in a general estimate where the surface 

 gently undulates ; the material also varies greatly in cost, arising, in 

 the case of tiles, in the supply being near at hand and equal to the 

 demand or otherwise, and, in the case of stones, in the distance of 

 carriage. 



" It was formerly considered that the cost of drainage was equally 

 divided between that of the labour and material ; and in 2| to 3-feet 

 drains filled with stones or horse- shoe tiles, on soles, this is about the 

 case ; but the more general introduction of pipes, and the improved 

 methods of making them, have occasioned a considerable balance in 

 favour of material, while increase of depth has increased the cost of 

 labour. 



" This latter item can be determined with sufficient accuracy by 

 referring it to a standard pretty generally known, viz., the value of 

 moving a solid yard of earth of any one description of hardness ; and to 

 illustrate this I have drawn up the following table, which supposes two 

 sets of drains, the one open for stones, the other for tiles, and at 

 depths of 3 feet, 3| feet, and 4 feet respectively. I have shown the 

 average width of the cutting for each size and sort, the number of 

 lineal yards required to equal a solid yard in each ; and assuming 

 three descriptions of soil, the differences in hardness of which make 

 the cost of moving their solid yard 4d., 6d., and 8d. respective^. I 

 have calculated the labour value per yard and per rod linear of the 

 different depths and sorts : and these will be found to tally very closely 

 with the prices at which the work is done. 



" It is a common remark that the cost of making drains is double 

 by every foot of increased depth given, and the same in proportion for 

 every part of such increase. The following table shows that this is 



