88 
EXPOSITION AT VIENNA. 
try, has becn the supposed difHoulty of setting them prop- 
erly. In the large cities the agents usually keep experi- 
enced inen in their employ, who can lay down the tiles if 
desired. A few simple directions will, however, enable 
any skilful mason to fix them properly. 
The foundatioii must be firm and secure in all cases, so 
that there shall not be any settling or absence of equal 
support under all parts of the pavement. Cemeut mortar, 
without sand, is used in setting the tiles, so that a perfect 
bearing is obtained and all the joints are filled. The fol- 
lowing directions are copied, with ouly slight modifications, 
from those published by Messrs. Minton, Hollins & Co :— 
1. If there is no cellar or otber opening underneath the space 
intended for the tile pavement, the foündation may be brought up to 
within three inches of the proposed surface of the pavement with brick, 
gravel, brolten stone, clean stone clippings, or other solid waste sub- 
stances free from Chips and shavings, so that complete solidity may 
be secured. Upon this substratum a mortar of gravel and cement 
should be spread, leaving a depth of one inch for half-inch tiles, and 
of one and a half inches for one-inch tiles. A floating of cement and 
sand, in eqtial proportions, should then be spread one-quarter of an 
inch thick, over the cement and gravel layer. Upon this, when hard, 
the tiling may be fixed. 
2. The above method is equally applicable, as far as requisite, to 
places above a cellar or other opening below, provided a firm founda- 
tion is given by an archway of brick or stone, or other equally solid 
substance. But when there is only an ordinary floor or floor-joist, 
it is necessaiy that the surface of this floor should be four inches 
lower than the surface of the intended pavement. There being, at 
that depth, a strong flooring of plank dr rough boards, the mixture 
of cement and gravel, as above, may be spread upon it, and finished 
in the same manner. 
3. Wliere it is required to replace boarded flooring by tiles, and 
it is impracticable to lower the joists to the necessary depth, as 
mentioned in 2, the floor boards may be lowered by “ cutting in ” 
betvroen the joists, securing them below bj r Strips nailed to the sides 
of the joist, so as to leave a space three inches deep above the 
boards, and below the top of the joists. The space so obtained is 
then to be filled in. between the joists with the cement and gravel 
mortar, raising it slightly above the joists, and finishing off with 
cement and sancl, as described in 1. A flat, level surface of this last 
coating may be secured by striking off with a straight cd ge* sup-