Cream City Earthcache EarthCache
-
Difficulty:
-
-
Terrain:
-
Size: 
(not chosen)
Please note Use of geocaching.com services is subject to the terms and conditions
in our disclaimer.
Cream City brick is a cream or light yellow-colored brick made from
a clay found around Milwaukee, Wisconsin, in the Menomonee River
Valley and on the western banks of Lake Michigan. These bricks were
one of the most common building materials used in Milwaukee during
the mid and late 1800s, giving the city the nickname "Cream City".
Wisconsin clays may be divided into two basic types, residual and
transported. Residual clays are created by the disintegration of
rocks where they stand. Transported clays originate in the
decomposition of rock on the slopes and crests of high ground and
slowly work their way into the valleys with the assistance of
water. Since the number and variety of sources for a single deposit
of transported clay may be great, these clays tend to be more
complex. Milwaukee’s is a member of the Lacustrine group of
water-deposited sedimentary clays and was supposedly formed during
the successive advances and recessions of the ice during the
glacial epoch.
Although the state’s Lacustrine deposits are in a small area,
they are unusually deep, reaching in places over 100 feet in depth.
The reason for the rarity and unique color of Milwaukee’s
clay lies in its chemical analysis. Typically, the average clay
contains silica (silicon dioxide), lime (calcium oxide), magnesia
(magnesium oxide), alumina (aluminum oxide), iron (ferric oxide)
and potash (potassium oxide) along with insignificant amounts of
soda, titanic acid and manganese oxide. Since almost all clay
contains the same list of ingredients, it becomes obvious that
their proportions are the critcal factor. When compared with clay
used for making the more typical red brick, Milwaukee’s clay
has a very low iron content, but greater amounts of calcium and
magnesium.
By the mid 1830’s, brick makers in Milwaukee discovered that
the stratified clay beds along the shores of Lake Michigan provided
material that could be made into a durable cream-colored brick
which became so popular as to give the city its nick-name, "The
Cream City." The geology of the Milwaukee area made the bricks a
matter of convenience. There was an abundant supply of the clay
used to make the bricks in the Menomonee River Valley and along the
Lake Michigan Shore. While clay deposits throughout the Milwaukee
area produced cream brick, the clay could be removed easiest from
the steep banks of the Menomonee River Valley where brothers George
and John Burnham set up their business. The brick makers used a
strip mine technique to remove clay from the banks, and, as a
result, the valley was widened considerably. Generally top soil was
removed to a depth of about three or four feet. The stratum of clay
consisted of an upper, reddish-colored layer and lower grayish blue
layer. In some areas the usable clay layer was as deep as forty
feet.
The earliest brick making process in Milwaukee was crude and
required considerable hard work. Horses turned a large wheel in the
circular pit that mixed and tempered clay and sand. Then the
pliable mixture was packed by hand into molds so that it could be
fired in kilns for a period of a week or more. The Burnham
brothers, and one of their employees identified only as Mr. Martin,
revolutionized the brick making process by inventing the first
operable brick making machine in the U.S. that tempered the clay
and packed it into molds. The brick making apparatus allowed the
Burnhams to make their product faster and cheaper than their
competitors enabling a greater number of people to purchase a
product that previously had only been affordable by the more
affluent. The Burnhams eventually eclipsed the efforts of all other
Milwaukee brick makers combined.
Cream City bricks came in two more-or-less rough categories, common
and pressed. Common bricks were inconsistent in both size and
color. Their position in the kiln could cause colors ranging
between white and yellow-green because of the differences in
temperature. Whatever their color, it was frequently diminished in
effect by the moulding sand which adhered to the surface. Being
coarser and sandy, they tended to attract and retain dirt and
become black faster. Steam-pressed bricks, on the other hand, were
uniform in size and color. Having been subjected to terrific
pressure, they emerged with perfectly smooth faces and sharp,
square corners and had a metallic ring when struck. The absence of
sand in the mold left a cleaner, more uniform yellow color than the
common variety.
Although color was its most famous attribute, this venerable brick
was superior in other ways as well. It was more durable in the face
of weather and had a much harder texture which required four times
more fuel to “burn” than red brick. It is said that the
light color reflected the sun instead of absorbing the heat and
allowed the day’s temperature buildup to escape rapidly after
nightfall. Milwaukee's first cream brick structure was erected in
1836. As the turn of the century passed, advances in construction
methods and improved materials -- like concrete and steel --
brought an end to Milwaukee's brick-making heyday.
To log a “Found It” for this earthcache, you MUST
perform the following:
- The posted coordinates take you to a national historic landmark
sign on the front of a building made of Cream City brick. Thanks to
Ramie Camarena, Projects & Communications Coordinator, for
granting permission to use this building as part of our Earthcache.
Using the sign as your guide, send the answers to the following
questions to the owner of this earthcache (NOT in your “Found
It” log):
- What is the name/function of this building?
- It is a major component of what kind of system?
- What was its daily capacity?
- Observe the Cream City bricks used in the construction of this
building. Is the color consistent from brick to brick? What about
the size and shape? Based on the information presented above, would
you classify this as common or pressed brick?
- Now go out and find another structure made of Cream City brick
elsewhere in the city. You may already know of some. Otherwise, you
will probably have to do some internet research, but it
shouldn’t be too difficult. If you still have no luck, you
may email the owner of this earthcache for suggestions. Then
include in your “Found It” log:
- Photograph of your Cream City brick structure
- Identification of the structure by name if possible (i.e.:
Menomonee Valley sign)
- Location of the structure by nearest cross streets (i.e.: 13th
& St. Paul)
When performing this portion of the Earthcache requirements, please
use common sense: no trespassing on private property, observe any
posted parking restrictions and/or hours of operation, etc.
NOTE: DO NOT PHOTOGRAPH ANY BUILDINGS ON
THE GROUNDS OF THE VA MEDICAL CENTER! AS IT IS CONSIDERED A
MILITARY FACILITY, HOMELAND SECURITY HAS DISALLOWED IT.
Additional Hints
(Decrypt)
Jnag fbzr pbssrr jvgu gung pernz? Rnegupnpur ng Nygreen.