CHAP. VIII. THE BELL ROCK LIGHTHOUSE. 227 



of the base. He further pointed out that the pillar 

 should be surrounded by such an extent of rock as to 

 diminish the force of the waves breaking at its foot. 

 He also proposed that the floor of the lower room of 

 the lighthouse should be 50 feet above the level of the 

 rock, and from thence to the top of the platform 3 5 feet ; 

 making a total height of 85 feet to the platform or 

 gallery. He recommended that argand lights should be 

 employed, with parabolic reflectors ; and he suggested 

 for consideration the employment of carburetted hydro- 

 gen gas, then coming into extensive use for lighting 

 purposes. The cost of the lighthouse, so constructed, 

 he estimated at about 42,000. 



The Commissioners adopted Mr. Rennie's report, 

 and proceeded to Parliament for the requisite powers, 

 which were obtained in the session of 1806; after 

 which (on the 3rd of December following) they unani- 

 mously appointed him the chief engineer for conduct- 

 ing the work. At his recommendation Mr. Stevenson 

 was appointed the assistant-engineer to superintend the 

 operations on the spot, and under him were placed two 

 able foremen superintendents, Mr. Peter Logan over the 

 masons, and Mr. Francis Watt over the joiners employed 

 upon the lighthouse. Mr. Rennie was then requested to 

 report further in detail, with plans and specifications of 

 the various work, which he prepared and duly submitted 

 to the Board. In his second report of the 26th December 

 following, he entered at great length into the description 

 of stone to be used in the building, based upon a per- 

 sonal inspection of the quarries at Mylnefield near 

 Dundee, at Arbroath, and at Aberdeen ; and on his 

 recommendation it was determined to use blocks from 

 the Rubieslaw quarry at Aberdeen for the outer, and 

 Dundee stone for the inner masonry. He also repeated 

 his advice, that in carrying out the work, the plan of 

 construction adopted by Smeaton in the building on the 

 Eddystone should be mainly followed ; one of the few 



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