ABSTRACT OF PROCEEDINGS. 



xlix. 



7. " Note on the Edible Earth from Fiji," by the Hon. B. G. 

 CoRNEY,M.D.,Prof. David, b.a., F.G.s.,and F. B. Guthrie, f.c.s. 



The sample of edible earth, a soft, pale pink, clayey material, 

 with occasional lumps of chalcedony was collected by Dr. Corney, 

 near the northern coast of Vanua Levu. In addition to the 

 chalcedony it contains numerous angular and rounded quartz 

 crystals, from J" to J" in diameter, and small octahedral crystals 

 of magnetite. The earth is probably formed by decomposition of 

 a dacite tuff. Its analysis, by F. B. Guthrie, gave the following 

 results : — 



Moisture at 120° C 2-45 



Combined water 



Silica 



Alumina 



Oxide of Iron, Fe 2 3 



12-78 



41-53 



3509 



7-66 



99-51 



The oxide of iron can be dissolved out with hydrochloric acid. 

 The silica, alumina and combined, water are present in approxi- 

 mately the proportion required by the formula Al 2 3 (Si0 2 ) 2 (H 2 0) 2 ; 

 the substance appears therefore, to be a silicate of that composition 

 — probably kaolinite — with about 7'6 per cent, of uncombined 

 ferric oxide as mechanical impurity. 



exhibits. 



Mr. J. L. C. Rae exhibited portion of a pipe conducting water 

 down Birthday Shaft, Balmain, from the "water ring," shewing 

 the pipe incrusted with calcium and barium carbonates. The 

 incrustations had formed in about two weeks. 



Professor David exhibited a Phillips Maximum Thermometer, 

 with copper case, for observing and recording rock temperatures. 

 At the Balmain Shaft similar protecting cases of copper and glass 

 are used, but the thermometers are Negretti and Zambra's maxi- 

 mum type, recommended by the Underground Temperature Com- 

 mittee of the British Association. 



d— Dec. 6, 1899. 



