204 THE BERMUDA ISLANDS. 



diameter. "Tliis will give an area of about 600,000 square 

 yartls, and supposing the water to be 3 feet deep and only one- 

 sixth part of this to be in actual contact with the dead coral, 

 we have 100,000 tons exerting its solvent action. This would 

 give, were the sixth part of the lagoon water to be expelled 

 and replaced with fresh sea-water at each tide, and taking the 

 solvent action at only 10 ounces to each ton, an amount of car- 

 bonate of lime removed equal to about 3000 tons each year." 



Mr Irvine curiously asserts that while he does " not insist 

 that such an amount of carbonate of lime must year by year 

 be removed from the lagoon," he yet thinks that the " experi- 

 ments show that the carbonate of lime so removed may easily 

 exceed any additions to the lagoon by secretions of animals 

 living in it, or by coral sand carried into it by wind and waves 

 from the outer edge in the same space of time, and therefore 

 I think the balance of evidence is in favor of Mr. Murray's ex- 

 planation of lagoon formation." 



But Mr. Irvine does not inform us on what grounds he as- 

 sumes that this internal waste may exceed accumulation or 

 accretion by growth. The argument is of that nature which 

 assumes that a " large " figure can accomplish anything, or 

 cover a multitude of omissions. The removal of 3000 tons of 

 material annually from a comparatively small basin appears 

 like a large amount, but when this quantity is closely scru- 

 tinized its vastness largely disappears. A ton of limestone, 

 allowing a weight of 150 pounds to a cubic foot, is the equiv- 

 alent in a general way of 15 cubic feet ; 3000 tons will there- 

 fore represent 45,000 cubic feet of material. This amount dis- 

 tributed over an area of 5,400,000 square feet (600,000 yards, as 

 assumed by Mr. Irvine) would cover it to a depth of the rh of 

 ii foot, or the tV of an inch. In other words, this iv inch rep- 

 resents the annual waste according to Irvine; it is the equiv- 

 alents of a cubical block of rock of 36 feet dimensions. Whether 

 this amount is sufficient to satisfy the demands of the " solution- 

 ists " or not, I am not in a position to say ; but from my observa- 

 tions of the waste of the Bermuda-lagoon shores, and the organic 



