lxxvi. Timchri. 



deposits of secondary bauxite in the Christianburg-Akyma district were 

 obtained by me whilst President of this Society in 1897. With Curator J. 

 J. Quelch as our guide, companion, and friend, I and my family spent some 

 time early in that year in the district ; Quelch as usual in search of 

 zoological specimens, I enquiring into the physical nature of the soils, j 

 by chance noticed the occurrence of small blocks and gravel of hard 

 material all along the path from the riverside to the house at the summit 

 of the low hill at Three Friends, Akyma. I also saw that the tiny model 

 fort built by Commissary Thompson King whilst resident at Three Friends 

 was made of it. I collected samples and asked Quelch if he knew what 

 the stuff was. Quelch said that it was an indurated clay (exactly what it 

 is) and that there were very wide areas of it in that district. A few days 

 later Quelch and I recognised the same mineral at Christianburg in the 

 foundation -wall of the saw-mill and along the course of the mill- 

 stream. We also took samples from there. As I thought it was possible 

 the concretionary mineral might be phosphate of alumina similar to that 

 of Connatable, French Guiana, I afterwards analysed the specimens and 

 found that although they did not consist of phosphate of alumiua they 

 contained exceptionally high proportions of a hydrate of alumiua. 



Thus to a chance visit of the then President of the Society, 

 accompanied officially at the expense of the Society by the Curator of its 

 Museum, the colony, and I may add, the Empire and her Allies, are 

 indebted for the finding of the vast surficial deposits of bauxite of the 

 Guiauas. There is a most striking difference between the almost deserted 

 toy-fort crowned hill at Three Friends, Akyma of 1897 and the busy hive 

 of industry in 1918 which has been inaugurated there by the Demerara 

 Bauxite Company. The summit of the hill has disappeared and its 

 former site is now marked by a 1,000 feet of a working quarry-face of 

 bauxite, some 16 to 18 feet in depth of the mineral being in course of 

 exploitation. 



All enquiries tend to prove that Demerara and probably Berbice and 

 Essequibo contain vast reserves of this important ore of aluminium. 



There are also in the colon}' deposits of manganese-ore, of similar 

 lateritic origin to the iron-stone and bauxite, which have been found 

 since 1897. 



Mica. 



There are deposits or pockets of white mica (muscovite) in certain 

 of the pegmatite-dykes which emanate from the great masses of the 

 rauscovite-granite which occur in the near interior. The most promising of 

 these masses as a source of mica is the Makauria — Kalacoon — Penal Settle- 

 ment — Lower Cuyuni River granite. It is possible that the deposits in this 

 district may prove to be of commercial value. 



The pegmatites may also prove to be here, as in other countries, the 

 sources from which supplies of rare minerals of great technical importance 

 may be obtained. Their exploitation in search of such minerals is, how- 

 ever, a problem of the future. 



