438 



T. M. EEADE ON THE DATE OE THE LAST 



blown over the top, which I am 

 convinced is a large estimate, as 

 very little sand blows on to Burbo 

 Bank Road North, the eastern 

 boundary of the plot, we shall thus 



have 350x10x3=10500 cubic # 



yards of sand deposited in eight ^ 



years on a shore-frontage of 350 £ 



lineal yards — or 3*75 cubic yards ST 



per lineal yard of frontage per b 



annum. g 



Taking this as my unit of mea- % 



sure (and it is an exceptionally ^ 



large one), I find, for the 16 miles §£ 



of coast forming the western © 



boundary of the deposit, it will g. 



give 105,600 cubic yards per an- g" 



num as moved by the wind ; and S 



dividing the 272,588,800 cubic § 



yards contained in the 22 square % 



miles, 12 feet thick, it will give g: 



2580 years as the age of the whole ® 



deposit of blown sand if accumu- % 



lated at the assumed rate. ^ 



Since these calculations were g 



made, I have lately tested their » 

 accuracy in another manner. 



There is another plot in Serpen- * 



tine Boad, having a sea-frontage ,§ 



of 243 lineal yards, and contain- *% 



ing about 6500 square yards. 3 



Serpentine Boad was made from § 

 my sections and under my super- 



intendence in 1866 ; so that I had J 



every opportunity of ascertaining o* 



the respective levels. Taking JJ 



every thing into consideration, I J 



estimate that there has accumu- g 



lated over its whole surface an g* 



average depth of less than 2 yards g 



of sand (very little blows across g 



the road); so I think we may gl 



fairly take an average depth of 2 3 



yards as representing the quantity J 



of sand blown off the shore from cL 

 a frontage of 243 lineal yards. 

 This, extended over fourteen years, 



gives 3-81 cubic yards of sand per ^ 



lineal yard of frontage per annum. >g 



It is quite evident that the sand ° 

 cannot accumulate faster than it 

 sweeps off the shore ; but at other 

 points on the coast the sea is 



Highwatermark. 



Measured accu- 

 mulation of 

 blown sand. 



Dunes. 



Dunes. 



Dunes. 



•to 



1 



Co 



The Warren 

 covered mostly 

 with dwarf wil- 

 lows. 



Railway. 



I' 



Links of the W. 

 Lancashire Golf 

 Club. 



Marsh Lane. 

 Dunes. 



