LIGHT-HOUSES. 5Q5 



rally reduced by an elegant curve, concave (o the eye, to a diame- 

 ter less by at least one-third, and sometimes to half its original 

 base. From thence, its taper diminishing more slowly, its sides 

 by degrees come into a perpendicular, and for some height form a 

 cylinder. After that, a preparation of more circumference be. 

 comes necessary, for the strong insertion and establishment of the 

 principal boughs, ivhich produces a swelling of its diameter. Now 

 we can hardly doubt, but that every section of the tree is nearly of 

 an equal strength in proportion to what it has to r< sist ; and were we 

 to lop off its principal boughs, and expose it in that state to a rapid 

 current of water, we should Hud it as capable of resisting the 

 action of the heavier fluid, when divested of the greater part of 

 its clothing, as it was that of the lighter, when all its spreading 

 ornaments were exposed to the fury of the wind : and hence we 

 may derive an idea of what the proper shape of a column of the 

 greatest stability ought to be, to resist the action of external vio 

 lence, when the quantity of matter is given of which it is to be 

 composed." 



With these views as to the proper form of the superstructure, 

 Mr. Smeaton began the work on the 2d of April, 1757, and 

 finished it in August 4, 1759. The rock, which slopes towards the 

 S.W. is cut into horizontal steps, into which are dovetailed, and 

 united by a strong cement, Portland stone and granite. The 

 whole, to the height of thirty-five feet from the foundation, is a 

 solid of stones, engrafted into each other, and united by every 

 means of additional strength. The building has four rooms, one 

 over the other, and at the top a gallery and lantern. The stone 

 floors are flat above, but concave beneath, and are kept from 

 pressing against the sides of the building by a chain let into the 

 walls. It is nearly eighty feet high, and since its completion has 

 been assaulted by the fury of the elements, without suffering the 

 smallest injury. 



We regret that we cannot with propriety trace out the progress 

 of this great work, and shew with what skill and judgment this 

 unparalleled engineer overcame the greatest difficulties: we, how- 

 ever, beg to recommend to our curious readers Mr. Smeaton's 

 own Account of the Eddystone Light. house, not doubting that they 

 will be highly gratified by the perusal. According to the Requisite 

 Tables, this light-house is situated in lat. 60. 8 N. Lon.4. 24 W. 

 of Greenwich, or 4. 18. 23 W. of London. 



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