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Analyses made in Colombo of Ceyl&nese Varieties of Ironstone 

 and Limestone. By George Middleton, Esq. Apothecary 

 to the Forces. (Communicated by Sir James M'G rigor.) 



1. Rcniform, or Kidney-shaped, Brown Clay Ironstone. — 

 It occurs massive and globular: sometimes these are hollow, 

 (a hollow globular ball, weighing upwards of 21 lb. is in the 

 Museum at Colombo), surface sometimes marked with impres- 

 sed forms. Fracture conchoidal ; lustre semi-metallic ; ad- 

 heres slightly ttf the tongue ; streak pale-brown. Sp. gr. 

 = 3.793, of a specimen from Matelle, and forwarded by Dr 

 Knox for the museum ; 4.06 of a specimen from the eastern 

 part of the island. The constituent parts, after two careful 

 analyses, are as follows : — Silica, 10 ; alumina, 3 ; lime, 22.5 ; 

 magnesia, 8.5 ; oxide of iron, 50 ; water, 4 ; loss, 2. = 100. 



2. Gramdar Foliated Limestone. — Is white and translucent. 

 Sp. gr. n 2.853 ; constituent parts, lime, 50 ; carbonic acid, 

 42; silica, 2; magnesia, 2; water, 2; loss, 2. =i 100. It is 

 quarried at Kandy, and employed for building purposes. 



3. Common Compact Limestone. — Its colour Is greyish white. 

 Sp. gr. = 2.578 to 2.6 ; constituent parts ; lime, 52 ; carbonic 

 acid, 42; magnesia, 1.5 ; water, 2.5; Loss, 2. = 100. This 

 limestone was brought from Poaeloor Cavern, near Jaffna, and 

 was part of a collection of minerals sent by Governor Sir E. 

 Barnes to the Museum at Colombo. 



We have much pleasure in communicating the preceding 

 analyses to our readers, as they are probably among the first 

 regular analyses of minerals hitherto made in India. We feel 

 confident that Dr CoUier, President of the Colombo Museum, 

 to whom Mr Middleton's communication was addressed, who is 

 an intelhgent naturahst, and active medical officer, will continue 

 to encourage the taste for natural history and chemical minera- 

 logy in the East. 



