206 BUILDING ST0NE3 OF ST. JOHn's CATHEDRAL, iiRISBANE 



building stone for basements, a favourite combination 

 being sandstone as a super-stiucture on basalt, with which 

 very handsome results are obtained. 



While not in much evidence in the now completed 

 Cathedral, it has been used in parts of the foundations 

 of this building, and, as far as durability and strength are 

 concerned, it has fully proved itself under more severe 

 conditions than exist here. 



St. Patrick's Cathedral in Melbourne is built almost 

 entirely of this stone, with the result that it will long outlive 

 St. Paul's Cathedral, which is built of the Geelong freestone 

 and Waurn Ponds limestone, both of which stones have 

 already very much decayed. The crushing strength of 

 this material on a three-inch cube was found to be 10,5771bs. 

 per square inch, or 680 tons per square foot, a strength 

 more than sufficient for its use in this building. 



Conclusions. 



From the foregoing it will be seen that of the stones 

 in the Cathedral, the Harcourt Granite and Footscray basalt 

 used in the basement are stones of proven quality, and no 

 doubt need be felt of their lasting properties. 



The inside Helidon sandstone, owing to its compression 

 strength, its protection from the weather and its lasting 

 properties even when exposed, also promises a very long 

 existence. 



The outside materials, namely, the local tuff and the 

 Sydney freestone will determine the life of the building ; 

 of these the tuff from its texture and composition and 

 apparently wise choice should weather excellently, whereas 

 if any stones show signs of decay one would expect them 

 to be the Sydney sandstone in exposed conditions, where 

 it is finally carved, and the smooth- dressed tuff. The former 

 will, in the course of time, almost certainly fret in places, 

 as it has done in Sydney buildings, and being smooth- 

 dressed might be expected to exfoliate in other places, 

 that is, thin flakes a fraction of an inch thick, part from 

 the rest of the stone in a direction parallel to the surface, 

 as a result of the disturbances produced by the uniform 

 tapping over the face of the stone during dressing. 



In conclusion, I would like to extend my thanks to 

 Archbishop Donaldson, Mr. R. S. Dods, and Mr. T. Pye, 

 for information afforded me in connection with this paper. 



