l8 NEW YORK STATE MUSEUM 



irregularly, usually around the individual grains. In the Peeks- 

 kill sample (3) this cracking went so far as to cause the stone to be 

 broken into fragments the size of the mineral particles making up 

 the rock. The very coarse sample from Northville (14) suffered 

 badly. 



In the flame test one of the cubes, Nyack (4) remained intact 

 and most of the others were but slightly injured. The fine grained 

 granite from Grindstone Island (9) was the most visibly affected, 

 having a large piece broken off from the corner against which the 

 flame was directed. The gneiss, Little Falls (n), besides having 

 a small corner broken off developed some cracks parallel to the 

 banding. 



Under the action of the flame and water none of the cubes 

 remained uninjured, though in the Keeseville (7) and Northville (14) 

 samples only small cracks were developed. The Pine Island gran- 

 ite (i) was badly cracked, yet only a few grains came off the edge. 

 The Peekskill granite (3) was disintegrated, breaking up into its 

 individual grains and the Little Falls gneiss (n) was very badly 

 affected. The samples from Garrison (2), Nyack (4) and Grind- 

 stone island (9) were quite badly injured, while the coarse grained 

 Grindstone island stone (10) was less affected. 



