20 



NEW YORK STATE MUSEUM 



Fire tests on sandstones 



After having been heated to 5 50 none of the samples remained 

 uninjured, though in all cases, on slow cooling, the cracks 

 which developed were very slight and along the bed. The Warsaw 

 bluestone (19) was changed to a deep brown color and besides 

 cracking slightly along the bed, also showed some small transverse 

 cracks. The Oxford sandstone (16) also took on a brown tinge 

 because of the change in the condition of the iron present in the 

 stone. The sudden cooling damaged the stones to a slightly greater 

 extent. The Medina sandstone (17) seems to have suffered the 

 most, for it not only developed cracks along the bed, but split in 

 two and showed some transverse cracks. 



In the 850 tests all of the cubes except the Warsaw bluestone 

 (19) split in two along the bed, both after slow and sudden cooling, 

 and in all cases, except in the sample from Warsaw, slight trans- 

 verse cracks were developed. The Warsaw stone was not very 

 badly affected on slow cooling, but upon fast cooling developed one 

 open crack around three sides, along the bed. The lamination 

 planes of the Potsdam stone (8) were made more prominent as the 

 heat was increased. 



Under the action of the flame, but one sample, Oxford (16), 

 came through without losing a piece from the corner, but around 

 the corner were two series of cracks. The sandstones from Medina 

 (17) and Warsaw (19) had small pieces broken off, while the Pots- 

 dam sample lost a large piece. In no cases were any cracks devel- 

 oped along the bed. 



Under the action of the flame and water the cubes all suffered 

 the loss of the corners. The Warsaw sample (19) was split into 

 eight parallel plates. The Potsdam cube (8), besides being badly 

 broken at the corner, split in two along the bed. The Oxford stone 

 (16) lost a large part from the corner and upper edge and the sample 

 from Medina (17) lost a small portion from an upper edge, but devel- 

 oped a crack around three sides and along the bed. 



