﻿152 NEW YORK STATE MUSEUM 



stratification and passing by evidences of less and less decay into 

 the disintegrating layers of the sandstone and thence into the solid 

 rock. A typical section of the soil is given in this sketch, taken from 

 the excavation for Miss Shea's hotel which was being dug at the 

 time of my visit, on Mt Gridley, Amherst island. This includes a 

 section j' 4" from the surface, there being, from above down: 



(1) 6" of dark brown plant mold 



(2) 8" pure white sand 



(3) 8" deep black mold 



(4) 3' deep red residual soil retaining stratification lines and 

 pebbles (rotted) in place 



(5) 2' 6" reddish passing into yellow soil, running downward into 

 the rotting rock fragments and finally to the solid rock. 



White sand. In nearly every soil section on the red rocks 

 the eye is struck by the persistent thin layer of pure white glistening 

 sand not far beneath the surface. It occurs on all the islands, so far 

 as I have visited them. This sand is doubtless the original red sand 

 decolored by the organic acids which run downward from the vege- 

 table mold, have dissolved the iron oxid and perhaps by transfer- 

 ence have given the dark color to the layers which immediately 

 underlie. These highly pure quartz sands are so interesting in their 

 association and in their relation to this residual decomposition that 

 I present here analyses of them made by Dr E. W. Morley, who 

 precedes his report upon them by a statement of his mode of 

 treatment. He says : 



I first sifted the two samples, with as little friction as possible, 

 through meshes of 20, 40, 60, 80 and 100 to the linear inch. The table 

 inclosed shows the result. Then the two coarser educts from the 

 white sand were gently pressed with the finger, and the sifting 

 of this sample repeated, with the result shown. The coarser part 

 of the red sand consisted of small fragments of sandstone but 

 the fragments of the white sand were friable and fell into powder 

 finer than 100 to the linear inch. This renders highly probable 

 your suspicion as to the relation of the two sands. 



On analyses, the composition was found as in the first and 

 second columns of the table. It may be said that a trace of silica 

 was not separated from the alumina, that potash and soda were 

 not separated and that water was determined simply as loss. In 

 other respects the analyses were as accurate as can be made. 



In columns 3 and 4 the analyses have been recomputed as per- 

 centages of the w r eight found for silica. It is seen that every 

 soluble constituent of the white sand is less than in the red sand. 

 As the calcium oxid and sulfuric acid were in both cases equiva- 

 lent within the errors of determination, they have been entered 

 as calcium sulfate. 



