102 SCIENTIFIC SURVEY OF BLACKPOOL AND DISTRICT 



When a length of about 50 yards of toe has been prepared in this way, the 

 trench is excavated for the toe wall. This wall, which is 3 feet 6 inches wide, 

 is taken into about I foot 6 inches of solid clay, and to form the timber shuttering 

 to the front of the wall a timber waling composed of pitch pine is bolted to the 

 king piles, and close timber sheeting is driven into the clay and spiked to the 

 permanent waling. 



At the same time, a trench to form the main wall which supports the bullnose 

 is commenced, and brought up to the correct level by timber sheeting. This 

 wall is 3 feet 6 inches wide, and is taken down I foot 6 inches into the solid clay. 

 After a period of three days, the shuttering is struck, and profiles are set up to 

 give the stepping of the apron between the toe and the main walls. The sand- 

 filling to form the apron is then deposited in position, and after this has been 

 thoroughly consolidated 9 inches of 6 to 1 Portland cement concrete is placed 

 on the filling to seal the apron thus formed. The timber sheeting to form the 

 steps of the apron is then placed in position, and 6 to 1 concrete is placed and 

 tamped and screeded to give a suitable finish. 



The shuttering for the bullnose is then erected, this being held in position 

 by means of old tram rails let into the apron. Finally, the panelled wall and 

 seating which surmounts the bullnose is erected. 



The steel rails which have been used for the construction of the bullnose are 

 cut off to the required level by oxy-acetylene flame. This process is con- 

 tinued in 48 feet lengths, and the average rate of progress attained was 50 to 

 60 yards of sea-wall per week. At convenient distances bulkhead walls were 

 taken across so that the process of depositing the filling to form the promenade 

 could proceed. This was consolidated by a caterpillar roller, and when a 

 convenient length was completed, the kerbing and construction of the concrete 

 carriage-way and red concrete footpath was proceeded with. 



The greater part of the gravel used for the concrete in this work was re- 

 covered from the shore, and the filling was also obtained mainly from the 

 sandhills and the shore. 



From observation of the foreshore, the level of the gravel adjoining the wall 

 is constantly changing. It has been noticeable that after a severe S.W. gale 

 coinciding with a high tide, the foreshore level has been lowered by as much 

 as 4 feet in some places, so it will be realised that the precautions taken for the 

 protection of the toe, by the construction of the timber sheeting, are necessary. 



The length of promenade thus recently completed is 2,940 yards, and the 

 cost of construction £148,000. 



The writer would like to express his appreciation to Mr. D. J. Bell, the 

 Resident Engineer, and all under him who so ably assisted in carrying out 

 this work. 



In the construction of all these works described, 130 acres of land have been 

 reclaimed from the sea, while the area of the sands at low-water mark of 

 ordinary spring tides is 1,450 acres. 



There is no treacherous bottom or quicksand on any part of the foreshore, 

 but during south-easterly winds there is a deposit of river sludge in low places, 

 such as adjoining the piers. 



