DRAIXIXG RUNNIXG SANDS. 127 



same way as when tlie common tiles are used. But on 

 account of the land having- been but recently drained by 

 them, my observations are not sufficiently matured to justify 

 me in saying' that they are in all respects equally good with 

 the common tiles. I lind it sometimes diificult to get them 

 to fit close enough to each other, the ends not being quite 

 straight, and some of them curved in the middle ; therefore, 

 it is necessary to apply clay to most of the joinings. 



Of these running sands I have drained about 500 acres, 

 and when the plan which has been stated here at large was 

 adopted, which has generally been the case, the average cost 

 per acre was about 5/. 5.*?. ; that is to say, 1000 tiles, at 26.s. 

 per thousand ; 3000 bottoms, at lis. per thousand ; cutting", 

 1/. lO.y. ; and incidental expenses, 3s. : total, 5/. os. 



I shall now conclude these remarks by stating the result 

 of these operations in draining-, which indeed must be con- 

 sidered in conjunction with marling. The land in question 

 was an enclosure of barren heath, and had been considered, 

 and really was, previous to being- drained and marled, worth- 

 less. It has now become profitable tillage-land, and is 

 advantgeously cultivated under the four-course system. 

 But to attempt such a work witliout carrying out the two 

 great parts of agricultural improvement which these soils 

 invariably require, namelv, draining- and marling-, is, I think, 

 superficial and unwise, and is always attended with dis- 

 appointment and loss. 



Journal of the R. A. S. E., vol. vii. part i. 



Art. XXXI.— the PRINCIPLES OF DRAINING. 

 By Mr. Hewitt Davis. 



Experience had long- shown to me the important difference 

 between drains of 2^ and 4 feet in depth. Man}- 3'ears before 

 Mr. Parkes had written on the subject, and so satisfactorily 

 removed all doubts by his conclusive reasonings and experi- 

 ments, I had found out that the deepest drains were the 

 cheapest, most durable, and far more efl'ectual in all soils : 

 hence in all my practice I have long- since abandoned put- 

 ting- in any in arable land at less than 4 feet. I have re- 



