kilns may be obtained in a good season,
producing 487,500 1-1/4-inch tiles, and in proportion for the other sizes.

"It requires 2 tons 5 cwt. of good coals to burn the above kiln, full of
tiles."

[Fig. 46 - CLAY-KILN.]

Fig. 46 - CLAY-KILN.

A sectional view of this kiln is shown in Fig. 46, in which _C, C_
represent sections of the outer trench; _A_, one of the three fire-holes;
and _B, B_, sections of a circular passage inside of the wall, connected
with the fire-holes, and serving as a flue for the flames, which, at
suitable intervals, pass through openings into the floor of the kiln. The
whole structure should be covered with a roof of rough boards, placed high
enough to be out of the reach of the fire. A door in the side of the kiln
serves for putting in and removing the tiles, and is built up,
temporarily, with bricks or clay, during the burning. Mr. Hodges estimates
the cost of this kiln, all complete, at less than $25. Concerning its
value, he wrote another letter in 1848, from which the following is
extracted:

"The experience of four years that have elapsed since my letter to the
late Earl Spencer, published in the 5th volume of the proceedings of the
Royal Agricultural Society, page 57, has thoroughly tested the merits of
the temporary clay-kilns for the burning of draining-pipes described in
that letter.

"I am well aware that there were persons, even among those who came to see
it, who pronounced at once upon the construction and duration of the kiln
as unworthy of attention. How far their expectations have been realized,
and what value belongs to their judgment, the following short statement
will exhibit:

"The kiln, in question, was constructed, in 1844, at a cost of L5.

"It was used four times in that year, burning each time between 18,000 and
19,000 draining pipes, of 1-3/4 inches in diameter.

"In 1845, it was used nine times, or about once a fortnight, burning each
time the same quantity of nearly 19,000 pipes.

"In 1846, the same result.

"In 1847, it has been used twelve times, always burning the same quantity.
In the course of the last year a trifling repair in the bottom of the
kiln, costing rather less than 10 shillings, was necessary, and this is
the only cost for repair since its erection. It is now as good as ever,
and might be worked at least once a fortnight through the ensuing season.

"The result of this experiment of