Sebring Ohio Historical Society
126 North 15th Street
Sebring, Ohio 44672
In early American pottery of the 17th and 18th century, crude items were turned out by a
local potter, using native clays and crude glazes.  Many tried to emulate the skills of the
English, and many used back stamps that directly copied and gave the impression that a
piece had indeed come from Staffordshire.  Even English materials were used, including
English China and Ball Clays which were shipped over to Atlantic ports.  The first
potteries were in the mid 1600's and in the New York and New Jersey areas.
Legend tells that James Bennett came to America from England in 1834 and worked in a
New Jersey pottery packing house.  After heading west to Indiana, he met a man from East
Liverpool, Ohio and moved there to use the yellow ware clay he sought to produce. The
first kiln operated in 1840 with business partners Anthony Kearns and Benjamin Harker.  
The first kiln produced mugs, from which they made $250.  Part were sold down river and
part sold by wagon.  After each load came out of the kiln, operations were suspended until
the ware was sold. In 1841, he sent for his three brothers to come over, and set up shop in
the south side of Pittsburgh, making the first Rockingham in the US.  He left the area a few
years later, but Harker, Knowles and Laughlin developed white ware in the area.  The
Harker Pottery Plant was abandoned when they had the opportunity of securing the plant in
Chester that was vacated by E.M. Knowles China Company, which in turn relocated in
Newell.  Homer Laughlin is credited with using the first truly American back stamp, an
eagle with a British lion on its back.
In the 1900's, ceramists as we know them today were not being educated at universities.  
Instead they were required to work a certain period in every branch of the business and
came out well rounded.  The industry made huge strides in this century, with great demand
and lower costs driving the market.  Development and use of raw materials became a fine
art in itself, with the advent of the ceramic chemist.
Carloads of grayish blue material was shipped in by train carloads.  Imported English clay
was combined with other chemical elements to form the body of the semi-vitreous
dinnerware.  It was mined in Devonshire, Wareham and Teigngrace, England at a depth of
sixty to eighty feet below the surface.  It was largely an aluminum-silicate composition,
and in preparation, water, flint, spar, lime, magnesium and traces of other chemical are
The loads of clay were dumped from the train cars into large outdoor bins.  It was left in
the rain and sunshine elements which acted as a purifying agent.
Workmen then loaded the material into wheelbarrows, weighed it, and cast it into huge
mixers to be pulverized in the slip-house.  In the slip house a thin paste called slip is made
by adding water.
The material next left the slip-house in the form of very liquid mud.  The water is
extracted, and press cakes are formed.  It is thinly passed over a magnet which removes
the tiny particles of iron, a source of grief to a potter.  Iron liquefies in the kiln, expands,
and makes a colored spot where it isn't desired.
The monopoly in supplying clays to the USA eventually came to an end.  Whiteness had
always been regarded as a mark of the virtue of any dinnerware and was best obtained
through using English China and Ball Clay, which were inclined to burn to a near shade of
white.  Ball Clay is a term used for many clays. Ball clay is actually blue. It is usually
light in color and highly plastic. Unfortunately by itself, it is too slippery and fine for use
unless it is combined with sand, grog or coarser less plastic clays.
The English potters tried bringing out a cream or ivory body as something new.  Imported
to this country, it caught on well.  The reaction of the American Potter was immediate.  
Unfortunately for them, the US had much stronger clays than the English, but didn't use
them because of their inclination to burn to an ivory tone rather than pure white.  This clay
came from Kentucky and Tennessee, and most all USA manufacturers turned to exclusive
use of the kaolin available in North Carolina, Georgia and Florida.  Methods were
developed to remove mica and other impurities.  The kaolin that had been discovered
before the American Revolution in North Carolina was superior to what was currently
available at that time.  
Pug Mill
After the Civil War, potteries were described as One Horse
potteries.  A business would have an old horse who ran a
tread-mill to operate the slip-house where the clay was prepared
for use. Before the invention of  mechanical kneading of clay in a
pug mill, a hefty guy wedged the clay to get it into the proper
working condition by cutting it into sections with a piece of wire
and socking it down on a stone slab and repeating the operation
over and over.  Air bubbles were squeezed out.  After mixing the
batch and once more adding water, the clay is made pliable for the
worker, and is ready to be worked into shapes.
Most of all hollow ware also was the product of pressers, a
man who batted out he clay into a flat cake then pressed it
into each half of the mold by hand.  When the halves were
put together and tightened by a leather strap, he would take
a jolly stick and reached in and smoothed the splice.  This
man would have served an apprenticeship to reach this
skilled level.  He would begin at a discount work rate
where often at the end of a day's work he wouldn't have a
single piece of good ware.  Handles were pressed in a
separate mold and then stuck on after being trimmed and cut
to fit the body of the article.  Cup handles were made in the
same manner until a casting slip was developed in the
The complicated process of glaze preparations simplified over
the passing years.  In the 1900's, a pottery had to have special fritt
kilns, which were fired with coal, in which certain of the glaze
components that were soluble in water were rendered insoluble
by smelting them along with flint, feldspar, etc.  Enough would be
made to last several months at a time.  Glazes that were made to
be opaque and which were not to be stained or used over under
glaze colors contained a portion of tin.  Eventually, companies
specialized in creating fritt, and it arrived at the pottery ready to
use in bags.
A Glost Kiln was used for firing glazed pieces, decal-decorated
pieces, the firing is not as hot as the bisque firing nor as long.
Dipping Room
Originally, pottery was dipped into glaze in a dipping tub.  The dipper
deftly swished a piece of ware and then deposited it on the drip board
and later it was put directly onto the mangle.  A mangle was a system of
moving wire trays that proceeded through heated air to emerge at the
other end in a few minutes dry enough to handle.  The bottom 'foot'
would be sponged relatively free of glaze.  It was then placed again
into the saggers for a second or glost firing.  Pins are placed between
each piece to keep them from sticking.  It left a small mark where the
triangular pin touched the item, and is not to be construed as a defect.
With new methods, glazes are applied to pottery on a belt.  The
operation takes them through a spray of glaze where often a
heavier coating is applied to the face than to the back of the
Unfired dried green ware was placed in fire resisting receptacles
known as saggers. A Sagger is a clay pot or bucket in which pieces
of pottery are placed while inside a kiln to protect them from the
direct effect of flames.
Up to the 1920's, most every plant made its own saggers.  It was a
difficult occupation and was manned by hardy souls.  Special
sagger clay had to be provided and they had to manually put it into
a soaking pit.  After the addition of the proper amount of water it
was  aged or soaked for a few days.  Clay was put in layers with
grog.  The grog was created from broken saggers and clay that has
been fired and then ground into granules of more or less fineness. It
is considered a filler and added to clay bodies for several reasons,
it helps open a tight or dense body and promotes even drying,
which reduces warping and cracking, and reduces overall
shrinkage. These shards had to be ground by shoveling them into a
chaser mill where specially hardened steel rollers crushed them
against a slotted steel grid that allowed the grog to fall out.  This
grog performed about the same function of gravel in a cement mix,
giving strength to bear weight when stacked in tiers of 20 or more
in the bee hive type kilns.  These fire clay baskets were filled with
ware and sealed to prevent fumes and smoke from coming into
contact with the ware.  They were stacked on top of each other into
an immense domed shaped kiln.
There was very little change in the construction of kilns
before 1900.  There were difficulties in keeping the heat
even throughout the kiln with the center reaching greater
heat than the edges.  Glazing such ware could be very
difficult, as the heat changed the structure of the pieces to
reduce porosity.  On the outside perimeter of the kiln
were placed large items such as meat platters and other
articles likely to warp by too much heat, and cups and
saucers were placed in the center.  Ware near the door
would likely be not fully fired as it was nearly impossible
to close it off completely.
Slip plaster molds are filled with slip which reduces the water
content in a slip to that of most plastic clays, around 30% of total
weight.  The plaster absorbs water from clay. The excess slip is
drained off and the cast can be removed from the mould soon after.
Spaulding China had 50 casters working at the same time.  Each
one worked with 50-100 moulds.  At any given time, the shop could
be working with as many as 4,000 moulds at one time.  The mould
department made both new moulds and replaced used ones.  Each
mould could be refilled about 100 times, when it would be worn
out and destroyed.  Moulds were made out of plaster of paris.
Demise of Pottery Business
Louis Porter in 1927 convinced O.H. Sebring that combining several potteries together
would be a way to get them on Wall Street.  Offers of $20,000 per year salary were made
to many of the heads and 'Crown Princes' of the industry.  Joining the group was E. H.
Sebring, Knowles, Taylor and Knowles, West End Pottery, Smith -Phillips, and the
National China Company, Pope Gosser, Crooksville China, Coxon-Beleek and Carrollton
Pottery Company signed up.  While C.L. Sebring, Frank's son was ready to join, Frank
H.(Tode) talked his father out of it, keeping Salem, Limoges and Sebring Pottery and Leigh
Potters out of the group. The group was called the American  Chinaware.   It might have
done well, but for the crash of the stock market in 1929.  However, they also created their
own problems.  Sales were lost when patterns were discontinued in an effort at
consolidation.  Working capital became scarce, and supervisors had to be cut.  Many of
the plants shut down.
While there was a booming need for pottery during WWII to be made in the U.S., at the
end of the war things changed quickly.  Tastes and attitudes of people began to change.  
Labor difficulties began in all industries.  There were also changes in the practices of
businesses.  Orders were cancelled without notice, and suppliers were stuck with stock.  
The major competition for the Japanese market was the final blow to many industries, and
pottery was hit hard.  Wage rates in Sebring were the highest in the pottery industry in the
United States.
Pottery unions began calling for tariffs and import quotas in the 1950's but their alarms
went unheeded in Washington.
When Sebring's Royal China closed, it left the Homer Laughlin China Co in Newell, WV
the only one left in the US making vitrified china, traditional home dinnerware.
Late in the 1900's, the air brush came into pottery.  Technique used small spray guns about
the size of a pencil with a little container of paint.  No brushes were involved.  Air supply
controlled the application of paint through an adjustable nozzle by a decorator.  Primarily,
decorating was a woman's job.  They would sit at a table and each have a primary task,
painting on the eyes or shading faces.  Early on it was mainly used to apply a tinted edge
to dinnerware, usually an under glaze of cobalt blue.  Labor cost was about a penny per
Even when very little else is left of a society, its pottery remains, enduring thousands of
years of nature. Somewhere along the way, ancient man noticed that clay held water, and
began using it as a vessel. Eventually he left some in the fire, and it hardened.   From this
beginning, he became the first potter.  Around this ability, entire trade and art skills
developed.  Trade secrets were passed down from father to son, and potters obtained
higher social status.
The History of Pottery
Types of Pottery
Semi-vitreous ware does not attempt competition with imported vitreous.  80% of the
ware gracing American tables in the 1950's were this type, also known as porcelain or
semi-porcelain.  Semi-porcelain is more durable, withstanding chipping, crazing and
temperature change tests.
Porcelain is translucent pottery with a body which is non-porous, non-absorbent, or
vitrified.  To be true porcelain, a piece should show the shadow of your hand when held
before light. When a piece of porcelain is gently struck, there should be a clear, bell-like
tone.  Vitreous China is as a rule translucent.  It is less durable and chips easily.
A trolley car moved the pliable clay to a jigger line, a series of potter's wheels. Jiggering
is a process for making plates and other fairly flat items. A pancake of clay is  slapped
over a plaster of paris mould shaped to the form of the desired plate that represents the top
of the piece, pressed down and spun. A template representing the outline of the underside
of the piece is placed against the clay and finishes the shaping. The potter used water with
his hands to shape the clay on a wheel.  The wheel and the mould that is affixed to the
bottom of the piece shape it, and a steel blade cuts off the excess. Jiggering machines were
created to speed up this process. That mould is then placed on a moving rack that takes it
to a heated drying room until it is dry enough to handle.  This is what is known as green
Green ware
During the drying process, the green ware
shrinks about ten percent and loosens from the
mould.  It goes to the finisher, who sponges the
ware and remove the rough edges.  Fettling is
the removal or trimming away of excess clay,
unwanted blemishes, seams and flash from
nearly dry pots prior to glazing and firing. It
went to the green room, where it dried further.  
Workers moved it around the plant on a four foot
board placed on their heads, and piled on top of
each other.  The ware could not be handled
A kiln is an insulated box, which is heated to fire pottery in. They
can be either, cross draft, down draft, or up draft. The draft refers
to the direction the combustion gas has to  travel from input to exit
flues. Since no combustion takes place in an electric kiln there are
no input or exit flues and they are genuinely heated boxes. The fuels
used to heat a kiln are gas, oil, wood, coal (now almost obsolete)
and electricity. Each fuel source used to fire a kiln offers different
possible outcomes for the pottery fired in them. The maximum
operating temperature for most pottery kilns is about 2372 F.
Kilns were constructed of several thicknesses of fire brick,
reinforced by heavy steel bands, and the floor was twenty feet in
diameter and was 18 feet tall.  The door of the kiln was then sealed
with bricks and reinforced with two steel bands.  Heat in kilns was
slowly introduced from underneath.
After firing, the bisque room takes over.  It is brushed, stamped with a
trade mark, dressed and prepared for further processing in the dipping
room.  After the invention of tunnel kilns, the need for Bisque saggers
was removed.  Instead the ware was set on shelves made of
White Ware Dressing Room
If the pins did not fall off the piece, employees removed them with a file in the
dressing room.  Pieces were also graded for quality at this time.  They were sorted
into firsts and seconds, and then the first were divided into selects and firsts.  The
seconds were also graded into seconds and thirds, making four grades, Select, first,
second and thirds.  The white ware is stored until time for decorating.  At American
Limoges, this stock room alone, at any time could contain 5 million dishes.
Decorating and Lining
In the early days of pottery, pieces were hand
painted.  It was both expensive and tedious.
The English method was to use a system of engraving
the design on a copper plate about 14 x 14".  The
printer who worked at a coal fired stove placed the
plate on the top and deposited a gob of color which he
worked into the engravings by the use of a 'spud'.  He
then took a long pliable spatula with which he cleaned
the surface and then as a final gesture took the heel of
his palm and gave it the final touches.  Then he took a
brush and sized a sheet of thin tissue the same size as
the plate using a soft soap solution,  This he laid over
the plate and then ran it through a roller-press much as
you may have seen done in the printing of engraved
calling cards, etc.  The heated plate had softened the
color preparation and now dried the printing paper
onto which the color design had been transferred.  A
cutter, a transferer and a couple of 'rubbers' made up a
crew, working on a piece work basis.  The cheaper
patterns comprised only this treatment and were
known as 'plain prints'.  For more elaborate effects,
these plain prints which had mostly been designed
with open flowers, etc., now went to the 'fillers-in'.  If
it was to be a four color job, there were four girls
each one supplying her particular color.  Festooned
edges were much in order then and it would go to the
'gilder' who would not only put on the edge line with a
camel's hair brush, but would delicately hand trace
much of the so-called rococo work.  Gold was then in
use but a bit earlier, most of the lining and hand
embellishment was done in a copper luster
Firing Kiln
Overglaze - when decorations are applied to the pottery after the
glost-firing, they are known as overglaze decorations. The colors
are apt to be brighter and sharper. You can identify overglaze
decorations by running your finger over the pottery from the
background to the decorations. If you feel a change in texture, it
is an overglaze.
The decorating kiln bakes the pottery at more than 1,500 degrees
Fahrenheit.  The heat causes the aniline oils and color bands of
the decoration to fuse with the piece and becoming
indestructible, an advantage over hand painted pieces.  In the
1900's, the old English type of double decorating muffle-kiln
was used, mostly fired with coal.  East Liverpool, on account of
its proximity to West Virgina used natural gas firing long before
other plants used it.  Potteries then considered where they would
move to based on the price of coal shipments.  In order to help
get the Sebring's to locate where they did, the PA Railroad gave
them the same rate by warping the rate boundary by several
miles and taking title to the ground needed for sidings for the
industries.  Modern potteries load items into fire retardant cars
that revolve on a steel track for more efficiency.  This process
was invented by the Ohio State University and Harrop Ceramic
Company.  It took a car about 24 hours to make a complete
revolution during glost firing, and 48 hours for bisque.  The kilns
measured from 35 to 105 feet in diameter.
Packing and Shipping
Items are carefully inspected and graded again, then sent to the
packing room.  Ware was packed into barrels, boxes and cartons.
The English used flexible crates made of green withes.  It looked
flimsy, but could withstand an ocean voyage if well packed.  
Casks of hogsheads and barrels were standard up to the 1910's.  
Wooden crates were used for sets of from 31 to 66 pieces.  
Barrels took the 100 piece set.  Each pottery usually had its own
cooperage shop.  These shops were on piece work and made
good money. Cartons were introduced in 1912.  Railroads
charged a 15% penalty for using cartons until potteries worked to
remove the tariff.   In early times, straw was used to pack, later
cardboard was used.  During WWII, it was not uncommon for the
boxes being used to be recycled from other uses.
Charlie Pinkerton working the Jigger
Moistening vats
Compound mixing room
Back stamping
Back stamps have more of a significance now than they did at the time the pieces were
created.  A single company may have used many, or none at all.  They could have pattern
names or production dates.  A new back stamp could have been created just to show off a
new pattern or line.
Migration of Potteries
East Liverpool, Ohio at one time had 35 separate
pottery plants.  Because of space limitations, they were
all multi-storied buildings.  Few had a railroad siding,
so that clay had to be carted long distances.  Ware was
also carried up and down stairs in baskets on men's
heads in two story kilns.  Labor was cheap and backs
were strong, but it didn't make up for all the breakage.  
It became obvious that a level ground production was
necessary. With so much land undeveloped, the
potteries would have room to build and grow.
That is what made the Sebring, Ohio site so attractive.
Decalcomania & Stamping
In the 1900's decalcomania began coming in from Europe.  The first to use it heated the
ware and then pressed the design on.  Results left much to be desired.  In the 1900's, gold
stamping replaced hand tracing and in 1910, piece work price in Sebring was a penny per
dozen for gold borders.  Stamps were seldom more than a couple of inches long, so
several stamps would be required.  By the mid 1930's, machine stamping was used.  Every
company developed its own equipment.  Royal China was noted for an excellent process.
After the invention of decalcomania, most dinnerware, even some of the expensive kind
were decorated by this transfer process.  Highly skilled women completed this job.  One
person would apply a coat of sizing or adhesive to the ware.  It then went into a drying
oven.  The decal was applied and rubbed well.  It then passed through a  mechanical
washer which removed the paper backing.  After drying the ware was hand painted with
color lining and gold band work.  Others did the gold handle work.
Toilet ware was of considerable importance in the 1880-90 era.  Sets could be highly
decorated, going through the decorating kiln as many as five times.  Tinting was done
through the process known as ground-laying.  An oil preparation was brushed on the ware
or applied with a boss where the color was to be in evidence. Then after drying for a
while, the finely powdered color was dusted on with a cotton boss.  It was an unhealthy
Even back in the 1890's, many 'schemers' were abroad selling chinaware to general stores
and others for premium purposes.  Robert Johns of Chicago was one of the earliest
operators and he gave many of the men who started up for themselves a good primary
training.  Later such folks started the Great Norther Mfg. Co., which made a killing in
several lines.  A chap named Kane made big selling a coupon plan to flour-millers.
Newspapers were also a big factor in sales. In the 1900's, J. H. Stouffer conceived the
plan of selling the idea of newspapers putting out canvassers who received a down
payment of 50 cents with each order from a new subscriber who would agree to take the
paper for a year and pay an added 5 cents per week.  At one time he had over 25 carloads
on order.  This subsided when WWI began.  
Bloomberg began a huge plan involving newspapers in NYC, coupons and redemption
sites.  Others came along using the same tactics, and they spent a lot of time suing each
Drug stores have distributed large quantities of china on various coupon and punch-card
plans.  People's Drug used over 150,000 32 piece sets from Salem in the 1930's.   The
housewife paid $2.98 for a set costing about $2.72 at the factory.  
Food chains used about 130 car loads of Salem dinnerware by American Stores of
Philadelphia on a punch-card deal.
As early as 1901, Mothers Oats and others were packing a piece of dinnerware in each
package of
rolled oats.  The largest items were either a pie plate or bread and butter plate.
Sam Hutmacher
Royal China
age 17, 1912
Clay Storage site
Boxing - rim to rim nestling of pottery bowls or cups to
prevent warping while drying and firing.
Cones are composed of clay and glaze material, designed to melt and bend at specific
temperatures. By observing them through a small peep hole in the kiln it is possible to
ascertain the exact conditions in the kiln. Cones are a better indicator than temperature
alone as the degree of glaze melt is a combination of time and temperature. Cones are
numbered from cone 022 up to cone 42. Cone 022 is the lowest melting cone and
requires the least amount of heat to deform or bend. During firing, a cone softens and
melts as it is heated. Cones used on the kiln shelf bend due to the effects of gravity
pulling the tip down. This bending indicates the cone and the piece of pottery has
received a specific amount of heat. It typically takes 15 to 22 minutes for cones to
bend fully once they start bending. Each higher cone number requires more heat to
bend. A cone 01 needs less heat treatment than cone 1 and cone 020 needs less than
019. Although cones do not actually measure temperature, cone bending behavior and
temperature are related. The faster the firing, the higher the temperature required to
bend the cone and the slower the firing, the lower the temperature required to bend the
cone. The 6 o'clock position, 90 angular degrees, is considered the end point of cone
Peep Hole - kilns have two
or three sections stacked on
top of each other and each
section has a one inch hole
that has a removable ceramic
plug that can be removed to
check progress of firing by
looking at cones.  Pixie B.  Pottery and Ceramic Magic
see this site for further definitions of pottery terms.
See also
Digitalfire Reference Database for even more details on the
making of pottery
Wall of the inside of a
glost kiln
The heat was increased to the correct temperature and kept there for 44
hours.  It was then gradually allowed to cool.  The ware removed from this
first baking is called biscuit or bisque.  It is now semi-vitrified, or partly
glass formed, though still porous.
Bisque is a greenware piece of pottery that is fired at a high temperature
and is porous and unglazed. The pottery is easier to handle due to the
hardness and warping from shrinkage can be controlled a little easier by
setting the pieces in sand during the firing.
Due to it’s porosity it is easier to get a glaze to adhere to it. The
temperature range for firing is red heat 1562 F to 1832 F.
In the kiln, the clay goes through the slow chemical process of clay
becoming ceramic. Clay which is exposed to heat 1112 F looses its
chemically bound water molecules and can no longer be broken down by
water. Once this change has occurred it cannot be reversed.
Inside the glost kiln
Tunnel Kilns changed how pottery was made.  One of the first was built for
Limoges China in Sebring by Phil Dressler.  It was built solid up from the
floor.  It needed a very long building, which wasn't always available for a
pottery in a city.  Thus, circular tunnel kilns were invented.  While the old
style of kiln required the hand to run up and down steps carrying ware both
on his head and in his hands, the new kilns were all on ground level.
While the long-flame, low-sulphur coal from the Pittsburgh district met the
demands of potters in the E. Liverpool, Ohio for many years, fuel oil
improvements brought about new kilns.  At the F. A. Sebring plant a carload
of tanks were purchased at Nitro, WV, from an abandoned government
project.  Mostly the idea was to use #6 fuel oil which was the least
expensive and promised the most BTU's.  Oil was purchased from men who
kept office in their hat.  Every now and then some one would smuggle in a
carload from the Smackover field in Arkansas where the high sulphur content
played havoc with the kiln contents.  In zero weather the oil would be so stiff
a man could walk on the surface of the oil.  All cars had to have steam coils
in them so they could hook up with the boiler.  Same was true of storage
tanks and fuel lines.  Filters were continually clogged.
Orifices on burners went wrong and streams of
oil were impinged onto the brick work, to the
great glee of brick layers.  Burner salesmen
then sold them new ideas that caused even
more problems.  When the plants went back to
coal, the tanks were junked lest someone might
be tempted to try it again.
Natural gas was used for firing intermittent
burners in East Liverpool years before other
areas had it available.  However, the gas