450 
handspike, the man forces down the piston, and 
expresses the clay through the die. The pipe is 
received by a boy on a stick, loosely fitting its 
bore, which also gauges the length of each pipe; 
and it is then cut off by a wire, placed on a hand- 
barrow, and carried to the adjoining drying-shed 
by another boy. One man and two boys make 
about 1,800 per day of the smallest sized pipe. 
It is requisite that the clay be well washed and 
sieved before pugging, for the manufacture of 
these tiles, or the operation of drawing them, 
would be greatly impeded by having to remove 
stones from the small space surrounding the die 
which determines the thickness of the pipe. But, 
it results from this necessary washing, that the 
substance of the pipe is uniformly and extremely 
dense, which consequently gives to it immense 
strength, and ensures a durability which cannot 
belong to a more porous though thicker tile. 
The clay is brought from the pug-mill so dry 
that, when squeezed through the machine, not 
a drop of water exudes; moisture is, indeed, 
scarcely apparent on the surface of the raw pipe. 
Hence, the tiles undergo little or no change of 
figure whilst drying, which takes place very ra- 
pidly by reason of their form and slight sub- 
stance. They are placed in the kiln when con- 
taining only about 12 per cent. of moisture, in 
consequence of which there is but trifling loss 
in the burning ; and each shrinks about 15 per 
cent. in its length between its raw state from 
the press and when burnt; yet these particulars 
will vary a little with the nature of the clay 
used. A manufactory of pipe-tiles may be added 
to any existing brick-field, at an expense of about 
£100, and for a less sum where kilns and pug- 
mills are in use. ‘This estimate includes the 
machine with a single die, a pug-mill, washing 
apparatus, kiln, and drying-shed. The manufac- 
ture might be carried on throughout the winter 
by securing the raw pipes against frost. This 
would necessarily occasion some additional out- 
lay, but it is thought would not enhance the cost 
of the tiles, as the hands would not lie idle. It 
is a consequence arising from the small dimen- 
sions and weight, together with the comparative 
dryness of the tile when produced, which pro- 
perties diminish to a minimum the bulk of the 
material used, and the space required for manu- 
facturing and drying. Such an establishment 
would suffice for the annual production of 540,000 
tiles, which is equivalent to the annual drainage 
of about 240 acres of land, from 30 to 36 inches 
in depth, at a mean of about 20 feet between the 
drains, and at a cost not exceeding £3 per acre 
in clays and firm-bottomed soils, unencumbered 
with stones. Other important advantages at- 
tending the cylindric figure and light weight of 
the pipe-tiles, are the diminished cost of carriage, 
and the faculty of conveying them into the field 
by hand. 
Time is the only criterion for forming a per- 
fect estimate of the durability of such an article 
TILE. 
as the drain-tile; but density and toughness are 
acknowledged tests of good pottery; and it can 
scarcely be questioned that the densest tile will 
endure the longest in the ground. After a care- 
ful investigation of the solid contents and weights 
of the tiles registered in the table, the following 
facts appear as regards their density :— 
. Weight. 
Oz. 
T weeddale, 0:973 per cubic inch of matter. 
Etheredge, 1:091 ate 
Read, No. 1, 1°'138 5 
50 2, 1:174 55 
29 3, 1:204 a 
ie 4, 1°322 ees 
99 2, 1°401 99 
These results seem to be in strict conformity 
with the degree of preparation of the earth, as 
well as with the nature and amount of the force 
to which the respective tiles are subjected in the 
apparatus employed; and it is seen that the den- 
sity of the cylindric tile increases in the inverse 
ratio of the magnitude of the orifice through 
which the clay is expressed from the cylinder. 
It must, however, be borne in mind that, in 
order to render comparisons of this kind free 
from error, the clay of differently made tiles 
should be alike. 
An establishment, with all requisite appur- 
tenances, for making drain-tiles with Hatcher’s 
machine—a considerably different one from any 
of those already glanced at—may be set up on 
any estate or farm at a cost of £25 for the ma- 
chine, £10 for the pug-mill, £5 for the kiln, and 
£10 for the sheds and straw, or of £50 for the 
whole; and whenever the proprietor has made 
as many tiles as he wants for his own use, he 
may either continue the manufactory for the 
sale of tiles to others at a profit to himself, or 
sell his machine and his pug-mill_ at very nearly 
their original price. The machine, too, makes 
roofing-tiles of prime quality, at less than half 
the price of those made by hand, and of a much 
lighter, closer, and straighter character; and, in 
general, it highly recommends itself both by the 
simplicity of its construction, and by the small 
amount of hand-iabour required to work it. All 
clay intended for use throughout any season must 
be dug as early as possible in winter, in order 
that it may undergo the most thorough exposure 
to the action of air and frost and snow. Care 
must be taken if there are small stones in it, to 
dig it in small spits, and cast out the stones as 
much as possible, and also to mix well the top 
and the bottom of the bed together. It is almost 
impossible to give minute directions as to mix- 
ing clay with loam, or with marl when necessary, 
for the better working of it afterwards, as the 
difference of the clays in purity and tenacity is 
such as to require distinct management in this 
respect in various localities. But all the clay 
dug for tile-making will require to be wheeled 
to the place where the pug-mill is to work it; 
and it must be there well turned and mixed in 
Ee ee i ee EE) 
