xxii INTRODUCTORY CHAPTER. 



There is moreover a very extensive quarry of pozzolana on the 

 eastern side of James's valley, about a mile from the sea. In the 

 year 1807, my predecessor, Governor Patton, to whose talents 

 and indefatigable exertions the island is much indebted, first in- 

 troduced this valuable ingredient in mortar cements. It v»^as 

 pointed out to his notice by M. Joinville, who had been attached 

 to the suite of the Honourable Frederick North at Ceylon. This 

 pozzolana, mixed Avith one-third of Sandy Bay lime, hardens in 

 sea-water, and has withstood the beating of the waves for several 

 years without being in the least degree diminished or affected. 

 Even when used without any admixture of lime, or water, but 

 merely after spreading it dry, and beating it well together, it 

 soon consolidates after being moistened with rain into a mass 

 almost resembling stone. In some parts of James's Town it has 

 been used as a substitute for paving, and has been found to 

 answer that purpose, not being liable to crack ; nor is it in the 

 least affected by the heaviest wheel carriages. 



Limestone of excellent quality is in the greatest abundance.* 

 It is said to be a concretion of shells and sand, and sometimes of 

 clay. In consistence it is not harder than a sugar loaf, and is there- 

 fore easily calcined ; one bushel of coals producing ten of lime. 

 The mountains close to Sandy Bay, and not far above the level of 

 the sea, are chiefly composed of it. Lot's Wife Beach, adjoining 

 those mountains, is covered with a white sand, which consists 

 almost wholly of small fragments of limestone. On the opposite 

 side of the island, lime has also been discovered, particularly 

 near Banks's Battery, and at Rupert's Bay, and, it is said, 

 in Breakneck Valley. But there are neither shells, nor lime, nor 

 any calcareous matter in the interior of the island. 



At Rupert's Bay the limestone rocks project into the sea. It 

 would seem that sea-water has a tendency to harden, or perhaps 



* Part 1. Sec. I. page 2. 



