L36 
AMERICAN AGRICULTURIST. 
[April, 
Ihcl that we sell produce and kriug nothing 
back, 1 believe the whole farm will gradually 
increase in productiveness; Tlie plant-food an- 
nually rendered available from the decomposi- 
tion and disintegration of the inert organic and 
mineral matter in the soil will be more than 
equal to that exported from the farm. If the 
soil becomes deficient in anything, it is likely 
iliat it will be m phosphates, and a little super- 
phosphate or bone-dust might at any rate be 
profitably used on the rape, mustard, and turnips. 
The point in good farming is to develop from 
the latent stores in the soil and to accumulate 
enough available plant-food for the production 
of the largest possible yield of those crops which 
we sell. In other words, we want enough avail- 
able plant-food in the soil to grow 40 bushels of 
wheat and 50 bushels of barley. I think the 
firmer who raises 10 tons for every ton h 
ells 
ing left between the bricks to admit the air and 
permit rapid (Irvine When nearly dry, those 
KILN OF BRICKS. 
will soon reach this point,aud when once reached 
it is easy to maintain thi3 degree of fertility, 
Brick-Making. 
"When bricks have been molded, they are car- 
ried by boys from the molding-table in the 
molds to the drying-floor. This is a floor of clay 
and sand, beaten hard with rammers, and made 
perfectly level and smooth. It is dusted with 
fine sand, and the bricks, in their soft state, are 
turned carefully out of the mold on to it (see 
fig. 2), and allowed to remain for a few days 
^ 
Fig. 2.— STACKING BKICKS IN TUB DRIINO TARD 
Until they are partially dry and can be handled 
safely. As soon as this happens, they are re- 
moved and piled up into long narrow heaps, 
similar to low walls (see fig. 3), open spaces be- 
Fig. 3. — ARCHED FLCE OF BRICKS. 
intended for pressed brick are selected and car- 
ried to the press, which is a machine operated 
generally by one man ; 
sometimes, in large 
manufactories, the 
press is worked by 
steam. The brick is 
received on a table, 
the bottom of which 
is of polished metal ; 
polished metal sides 
also surround it. The 
table is carried be- 
neath a die, also of 
polished metal. The 
table is brought up- 
wards by means of a 
cam or eccentric, or a 
combined lever act- 
ing with great force, 
and the inclosed brick 
pressed until the re- 
maining water is 
squeezed from the par- 
tially dried clay, and it is compressed so much 
that even the sides take a smooth face from 
the polished surfaces 
brought into contact with it, 
and the edges are rendered 
sharp and perfectly square. 
These bricks when burned 
are known as Philadelphia 
fronts, or pressed brick, 
and bear a much higher 
price on account of their im- 2S? _ _J_. 
proved appearance. The 
common bricks undergo no process further than 
drying until they are ready for 
burning. They are then piled 
into a kiln, which is a large 
square heap, holding generally 
a hundred thousand or even 
three or four times that quan- 
tity, piled up loosely, so that 
the heat from the flues can 
pass through the interstices 
aud burn the bricks evenly 
and thoroughly. It is im- 
portant that the flues be built 
up properly. Fig. 3 shows the 
method of building the flues, 
which pass through the kiln 
from side to side, and in 
which the fires are placed. 
When the kiln is finished, it 
is plastered over with clay to 
retain the heat, and is gen- 
erally covered over with a 
rough shed, as a protection against the weather. 
This mode of building is adapted for burning 
with wood, forty cords of which, generally dry 
yellow pine or hemlock, is needed for a kiln of a 
hundred thousaud. If coal is used, the flues are 
mere draft-holes, sufficient to hold only enough 
wood to kindle the kiln, and fine slack coal is 
spread in layers between the bricks, and some- 
times mixed in the clay of which the bricks are 
made. Three weeks' constant burning is needed 
to complete the bricks, when they are ready for 
use. Bricks may be made for from four to six 
dollars per thousaud, if in a quantity not less 
than a hundred thousand, and we have known 
of farmers who, intending to build, have made 
a kiln of brick, and sold the residue after sup- 
plying their own wants for as much as the cost 
of the whole. Of course, the services of an ex- 
perienced brick-maker will have to be secured. 
A Wooden Bridge. 
— • — 
Country bridges are always useful, but rarely 
ornamental. Designed for strength, appear- 
ance is sacrificed to utility. It is often the case, 
however, that the ornamental may be combined 
with the useful with advantage. In bridges of 
a certain character this is essentially the case. 
A simple timber laid across a stream as a foun- 
dation for a bridge, although the simplest and 
plainest form of structure, is far from being 
the strongest. The truss of lighter materials is 
stronger than a single heavy beam, while the 
arch may be made lighter yet than the truss, 
with a still further gain in strength. We give 
a cut of a wooden arch, to be made of boards 
fastened together with nails and bolts, which 
may be built readily of materials always at 
hand, and needs no piece longer than twelve 
feet, even for an arch of forty feet span or over. 
Nor is it necessary even to lay a center on 
which to build this arch. It may be built up 
on the ground, a foundation of stakes or posts 
being made on a level place on which to com- 
mence ; or it may be built on a barn-floor, if of 
sufficient size, and when complete moved to its. 
place and set up. 
LLZa 
BRIDGE WITH WOODEN ARCHES. 
The mode of proceeding is as follows : We 
will suppose a bridge of twenty-four feet spaD 
is needed. The first necessity is to make the 
foundations for the arches. These should be 
built firmly of s' one or timber, and well backed, 
and steps made to receive the feet of the arches. 
If the bridge is to be twelve feet wide, three 
arches will be necessary. These are made of 
spruce boards, preferable as being elastic and 
tough, or, wanting them, pine or hemlock will 
answer, and twelve inches wide and one inch 
thick. The form of the arch is laid out on say 
the barn-floor, and a scantling tacked down 
for the base, with studs reaching from it to thfl 
line of the arch. A board is then tacked to tho 
end of the scantling, and bent round on to the 
ends of the studs, and tacked to them to hold 
it into its place ; another board is put to the 
end of this, until the other end of the scantling 
is reached, and the figure of the arch is com- 
plete. Other boards are then placed over the 
first ones, and wrought-nails driven through 
and clinched. The joints must in all cases be 
broken. Boards are nailed on in succession 
until a sufficient thickness is secured — twelve 
to twenty inches, as may be needed for a bridge 
