Building Materials, 



29 # 



almost any shape, and its cheapness compared to basalt or 

 limestone, render it suitable for cottages or other small build- 

 ings, where there is no great pressure on the walls ; but all 

 building stones of similar properties ought to be rejected in 

 extensive erections. 



The Toorak sandstone, as I am informed, is from the same 

 formation as that of Boroondara. It is composed of very fine 

 water worn quartz grains, and minute plates of white mica, 

 with an argillaceous base. It is deeply tinged with iron 

 oxide in patches and streaks ; none of the specimens in my 

 possession being of a uniform colour. The Aveight of a cubic 

 foot is 145 lbs — the maximum being 147 lbs., and minimum 

 143 lbs. It is easily frangible. It may be Avrought in large 

 masses. It absorbs water very quickly, and to a great extent. 

 It gains 3*952 per cent, by weight if immersed for a few 

 minutes ; and a piece that was placed on its end in water for 

 ninety-six hours showed an increment by weight of 5' 109 

 per cent. In comparing the sandstones, one with another, it 

 will be observed that some very rapidly absorb their maximum 

 quantity of water, and others very slowly. The close grained 

 sandstone from Geelong, for instance, gains "336 by simple 

 immersion, but the actual amount that it will absorb, if 

 sufficient time is allowed, may be stated at 3 "831. 



Subjecting the Toorak stone to the usual tests it is soon 

 destroyed. Such of the specimens as I have met with are not 

 suitable for building purposes, all of them possessing features 

 similar to the above. A small piece that was placed in a 

 vessel containing sufficient water to moisten the lower portion, 

 was soon completely saturated, the cavities of the stone acting 

 like so many capillary tubes. With such a stone for outer 

 walls a house woidd be always damp and cold in winter ; a 

 matter of deep importance to the health and well-being of the 

 occupants, which ought ever to enter into calculations of this 

 kind. 



A deeper section of this quarry may probably afford a less 

 perishable material, and such a discovery would be of the 

 greatest value at the present time. 



For durability, beauty, and economy, the sandstones are 

 undoubtedly of the first class. 



The lightness, and architectural elegance of the buildings 

 in Edinburgh, which are so famous, are due to the circum- 

 stance of the sandstones being there procurable of a superior 

 quality. Perhaps it would be impossible to construct such 

 edifices of any other material, which at once combines hard- 



