PLYMOUTH BREAKWATER. 191 



sights that can strike a friend to the great works of art. At fixed hours the sound of a 

 bell is heard, in order to announce the blasting of the quarry. The operations instantly 

 cease on all sides ; all becomes silence and solitude. This universal silence renders still 

 more imposing the noise of the explosion, the splitting of the rocks, their ponderous fall, 

 and the prolonged sound of the echoes." 



" The waves," said Rennie, " were the best workmen " in the construction of a 

 breakwater of rough stones, and on the whole his belief was confirmed, for the storms by 

 which his great work was assailed rather helped than hindered it, by showing the most 

 desirable slope on the sea-side, while comparatively little damage was done. The slope of 

 the stone barrier was, however, by their force changed very greatly. An inclination of 

 three to one was altered to about five to one, and Rennie had recommended that the 

 authorities should take a lesson from nature and finish the breakwater according to her 

 teachings. " It would appear/' says Mr. Smiles,* " that Mr. Whidbey, the resident 

 engineer, contrived to finish most of the exterior face at a slope of only three to one, as 

 before; and that it stood without any material interruption until several years after 

 Mr. Rennie's death. By that time nearly the whole of the intended rubble, amounting 

 to 2,381,321 tons, had been deposited, and the main arm, with 200 yards of the west 

 arm, making 1,241 yards in length, had been raised to the required level. The work had 

 .arrived at that stage when it had to experience the full force of another terrific storm, 

 which took place on the 23rd of November, 1824. It blew at first from the south-south- 

 east and then veered round to the south-west, and the effect of this concurrence of winds 

 was to heap together the waters of the Channel between Bolt Head and Lizard Point, and 

 drive them, with terrific force, into the narrow inlet of Plymouth Sound. This storm 

 was not only greatly more violent, but of much longer duration than that of 1817. 

 When the breakwater could be examined it was found that out of the 1,241 yards of the 

 upper part, which had been completed with a slope of three to one, 796 yards had been 

 altered as in the previous storm, and the immense blocks of stone which formed the sea- 

 face of the work had, by the force of the waves, been rolled over to the landward sides 

 thus reducing the sea-slope, as before, to about five to one. The accuracy of Mr. RenmVs 

 view as to the proper slope which was indicated by the action of the sea itself was thus 

 a second time confirmed;" and a board of eminent engineers reporting in accordance, the 

 work was so finished. When the action of the sea had formed its own slope and had 

 wedged together and settled the great mass of materials which form the breakwater, and 

 when no further movement was apparent, but the whole appeared consolidated together, 

 then the slope towards the sea was cased with regular courses of masonry, dove-tailed 

 and cramped together, the diving-bell being brought into requisition for placing the 

 lower courses. A lighthouse has been erected 011 its western extremity, and the work may 

 be regarded as a magnificent success, worthy of a great maritime nation. 



A third leading illustration of a magnificent breakwater is afforded at Portland, and it 

 is deserving of particular mention inasmuch as all authorities agree that it was constructed 

 with little or no waste of the public money. " In the mind of the inquiring tax-payer/' 



* " Lives of the Engineers." 



