BUILDING AND ORNAMENTAL STONES OF N.S.W. 



195 



Effect of Heat on New South Wales Building Stones — continued. 



No. Rock Treated. 



Temp, of 

 Furnace 



°C. 



Time in 

 Furnace 

 Minutes. 



How Treated and Remarks. 



30 



31 



32 



33 



34 

 35 



36 



37 



and 



38 



Fernbrook 

 Marble 



695 



Caleula 

 Marble 



695 



35 J) 



695 



Springhill 

 Marble 



656 



5? 55 



Windellama 

 Marble 



656 

 656 



35 3) 



656 



! 



30 



30 



30 



45 



45 



45 



BlueBorenore 648 

 Marble 



45 



30 



The furnace was gradually- 

 heated up to this temperature 

 when the specimen was taken 

 out and a spray of cold water 

 played upon it. The original 

 colour was quite destroyed 

 although the edges remained 

 intact but calcined. 



Ditto, ditto, ditto, colour not so 

 obliterated as 29 and 30, but 

 more edges were calcined. 



Ditto, ditto, but edges still 

 further calcined. 



Similar condition to No. 35, but 

 very much less affected, origi- 

 nal structure still retained and 

 much of the colour. 



Ditto, ditto 



The furnace was gradually 

 heated up to this temperature 

 during this time, when the 

 specimen was taken out and a 

 spray of cold water played on 

 it. The original colour was 

 quite destroyed on the surface 

 and specimen cracked. 



Similar conditions to 35, but 

 after half an hour the speci- 

 men burst with a loud report 

 into four pieces. 



Placed in a furnace heated to 

 this temperature and left for 

 half an hour. Fared badly, for 

 when the stream of cold water 

 was played upon them they 

 cracked in several directions, 

 lost original colour and became 

 almost calcined. 



All the above specimens are now placed permanently in the 

 Technological Museum, Sydney. 



M— Oct. 6, 1909. 



