CHAP. X. 



PLYMOUTH BREAKWATER. 



263 



rubble deposited to the end of 1848 when the work 

 may be said to have been completed was 3,670,444 tons, 

 besides 22,149 cubic yards of masonry, or an amount of 

 material at least equal to that contained in the Great 

 Pyramid. The whole cost of this magnificent work was 

 a- bout a million and a half sterling, including a conve- 

 nient and spacious watering place at Bovesand Bay. 



As forming a convenient and secure haven of refuge 

 for merchant ships passing up and down Channel, along 

 the great highway between England, America, and 

 India as a capacious harbour for vessels of war, wherein 

 fifty ships of the line, besides frigates and smaller vessels, 

 can at all times find safe anchorage Plymouth Break- 

 water may in all respects be regarded as a magnificent 

 work, worthy of a great maritime nation. 



jacent, the lower parts of the granite 

 bonding courses being laid level, but 

 the upper parts forming part of the 

 slope- . It was still found that there 

 was a difficulty in preventing the 

 outer edge or base of the sea slope, 

 where the main lower granite bonding 

 courses were placed, from being under- 

 mined by the waves ; and it was de- 

 termined to place a trenching or fore- 

 shore on the outside of the sea slope, 

 40 feet wide in the centre of the 

 Breakwater, increasing to 50 feet wide 

 at the commencement of the western 

 arm, and diminishing towards the 

 eastern arm to the width of only 

 30 feet. This foreshore was about 

 2 feet above the level of low water 

 of spring tides next to the toe or 

 base; and the surface was roughly 



paved with rubble well wedged toge- 

 ther. The whole of the slope was 

 paved with well-dressed courses of 

 ashlar masonry without mortar, 3 feet 

 6 inches deep, well bedded down 

 upon the rubble below. The ex- 

 tremity of the western arm was fur- 

 nished with a solid head of circular 

 masomy, 75 feet diameter at the top, 

 with slopes of 5 to 1 all round. At 

 the point at which the lighthouse has 

 since been placed, an inverted arch of 

 solid blocks was formed, the whole 

 well bonded, dovetailed, and dowelled 

 together, and firmly united with the 

 other parts of the solid rock. These 

 works answered admirably, and Ply- 

 mouth Breakwater now rests as firm 

 as a rock upon the bottom of the 



SECTION OF THE BREAKWATER A3 FINISHED 



