256 J. C. Branner — JEolian Sandstones of 



1. Specimen dried at 110°-115° C. : 



Silica ._ 1*77 per cent. 



Alumina.. 8'81 " 



Ferric oxide.. 6 35 " 



Lime _ _ 0*15 " 



Magnesia 0-13 " 



Calcium phosphate -_ 18*35 " 



Calcium carbonate 41*62 " 



Magnesium carbonate 22*17 " 



Potash 0-12 " 



Soda 0-48 " 



Loss on ignition 1*81 " 



Total 101*76 per cent. 



Water at 110°-115° C. ._ 1*44 " 



Soluble in concentrated nitric acid 95.94 " 



Insoluble in " " " 4-06 " 



Total 100-00 per cent, 



2. From the surface of the aeolian sandstone from Ilha Rapta. 

 Specimen dried at 110°-415° C. : 



Silica and matter insoluble in concen- 

 trated nitric acid _ 0-09 per cent. 



Alumina.. 0'45 " 



Ferric oxide 0-13 " 



Calcium phosphate _ 0-82 " 



Calcium carbonate 98*33 " 



Magnesia.. 0*64 " 



Potash _ 0-10 " 



Soda 0-20 " 



Total 100*76 per cent. 



Water at 110°-115° C 0*17 



Soluble in concentrated nitric acid 99-91 " 



Insoluble in " " " 0*09 " 



Total 100*00 per cent. 



It should be noticed also that the analysis of the very porous 

 rock from the Bahia do Sueste used for making lime shows the 

 presence of phosphate of lime. 



In his report upon the phosphate beds of Ilha Rapta Mr. 

 Derby refers to a piece of a Millepora having been found in 

 the higher parts of the calcareous sandstone beds of that island 

 and from this he seems to infer that they were deposited under 

 water. Of the many pieces of organic remains I have found 

 in this rock I have never seen one whose presence so high 

 above water might not readily be explained by supposing it to 

 have been blown up a gently sloping beach by the wind. The 

 place referred to by Mr. Derby is, however, a peculiar one in 



