Buarr.—On the Building Materials of Otago. 159 
the habitation of the living man; I find, however, that Mon. Coiquet, who 
has had more experience than anyone else, does not build excessively thin 
walls: those of a house of six floors and a cellar, erected by him in Paris, com- 
mence with a thickness of 19.8 inches, and terminate at the topmost story 
with 9.8 inches; the average being 13} inches, which is within three-quarters 
of an inch of the thickness required by the Metropolitan Buildings’ Act, for 
the wall of the same house in brick or stone. Concrete buildings in 
London are generally built to the same standard as brick; the walls of 
extensive carriage and engine sheds, lately erected for the Metropolitan 
District Railway Company, although only one storey in height, are eighteen 
inches thick, with piers at short intervals. From all this, it may be 
inferred that full advantage cannot be taken of the extra strength obtained 
by substituting concrete for brickwork, we must therefore rest satisfied in 
having raised the standard, by getting a stronger and more durable article. 
till, I think some little allowance might be made in the thickness of 
walls, perhaps the following would be a fair proportion to adopt, in building 
with the materials at present commonly used in Otago :— 
Concrete and betou ae cae eas 12 inches. 
Ashlar masonry ae we es ry eer 
Brickwork a a etd sis 18} |, 
Rubble masonry ... 1 
The increased thickness of walle 3 in fabbls masonry is dnt determined 
by deficient strength, but by the difficulty in building thin walls with rough 
stone. 
Cost. 
Having now discussed the properties of stone, bricks, and concrete, the 
materials of which the walls of our buildings are composed, I shall consider 
shortly their relative cost. Of course, timber is still in general use for 
walls as well as its more legitimate functions of roofing, and internal 
fittings ; but having properties and uses peculiar to itself it will be treated 
at length in another chapter. I shall, however, at this stage compare the 
cost of timber in the walls of buildings with those of the other materials 
mentioned. 
It is impossible to determine a general rule on the subject of cost and 
suitability, as they depend so much on the resources of the locality, and the 
purpose in view, not to mention the wider range of individual tastes. The 
following conclusions are applicable to Dunedin, but they will give at least, 
indications of results in other parts of the province, by making the 
allowance due to a difference in the value of materials and labour. 
It is authoratively stated that the cost of concrete in London is only 
one-half that of brickwork for the same thickness of wall, and the betou 
