Materials for the Construction of Cottages. 
563 
another ; but that is not always the case ; the cause is frequently to be 
found in the surface on which tlie tile rested, causing it to sink 
slightly, leaving another more exposed, in consequence, to wear. Nov^ 
the tiles exhibited rested one. ujion another on thin flanges representing 
a level platform, and the paving kept its level much better than when 
it rested solely on the soil. These tiles were made of Staffordshire 
clay, and were kiln-bm-nt ; they were all made in pairs, on the same 
principle as the blocks which he had before described. The com- 
mencing and the finishing tiles were produced from the same die ; and 
it was because of these facilities in manufacture these materials are 
cheaply produced. 
He now came to roofing. Tiling is better for that purpose 
than slating ; but in and around London it is much more costly, 
the difference being 35 per cent., at least. The great advantage 
of slating is that it requires less strength of timber. Ordinary 
plain tiling is nearly three times the weight of slating, because 
it has to be doubled in order to keep out water. A tiled roof is 
much warmer in winter and cooler in summer than a slated roof. 
NoAV, he had invented a roof -which was only half the weight of plain 
tiling, and very little heavier than slating, as it does not require to be 
doubled.* This tile is made with two side flanges, there being notches 
in the flanges. These notches allowed the tile when turned topsy- 
turvy to go down and take a level bearing upon the two side-tiles 
beneath. They also presented a level bed everywhere for the tile to 
rest upon. On the face of the tile there is a nib, which gives the 
gauge, secures the upper tile against the lower one, and when turned 
up is of equal use in keeping one down upon the other. The ridging, 
which is generally the most defective part of slate roofing, is adequately 
provided for in the same manner as the tiling, the ridge being merely 
a continuation of the tile. The upper ridge-tile rests ui^on the under 
ridge-tile, and the under ridge-tile upon the tiling, capping the whole. 
Thus, without any other aid, perfect dryness is secured in the most 
exposed part of the ridge. The ridge is mortared down and bedded in 
the usual way. 
There are many more points of construction to which atten- 
tion is necessary for the prevention of damp in cottages. They 
must have often observed how much window-sills, chimney-cappings, 
and other exposed parts requii-e what is termed weathering. Now, 
for that pm-pose he had formed what he called a drip-band, which is 
suitable in its formation for cottages. This kind of band is used at 
all the stations of the London, Chatham, and Dover Eailway Company, 
and therefore it has been sufiiciently tried. The band has a throat 
beneath it, which projects just far enough to allow any moisture to 
drip fi'om one band on to another, and thus wet is prevented from 
rimning down the face of the wall.. 
Mr. Tatlok said, in reply to an inquiry, that the depth beneath the 
ground-floor of the cottages described varied from six to ten inches, 
which is all that is necessary. The heavy expense required for 
* See Illustration No. 6. 
