It's Spring! And it's dry? Relative humidity is perhaps the most important factor in storing collections.

by Gwen Spicer

April showers, warm temperatures causing snow melt, and streams flowing up to the edges of their banks.  Each a sign of dryness.  Counterintuitive?  That may also be so, but it is true.  Even with all this water, Spring is actually the driest time of year, and if you have a collection of artifacts to care for, this is an important piece of information.

Creating a sympathetic environment is important in both display and storage areas to assure the long-term preservation of any collection.  The ideal environment includes controlled temperature and relative humidity, clean air with good circulation, controlled light sources, and freedom from biological infestation.  This can be difficult in historic structures due primarily to absorption of moisture during the winter heating months that is then not lost during the summer months.  However in simple terms, it has been found that by keeping a slightly wider window of acceptable humidity levels, and controlling the fluctuations, the collection and structures can remain well preserved.  The conservation and museum fields are slowly learning that one needs to find a HVAC system that meshes well with the building.  And of course there is a broad spectrum of needs.  What about historic homes that are closed through the winter?  Or museums that have separate storage, but have artifacts on display in a warm dry humanly comfortable display area?  Lots of dynamics, each one different, but at their core they all must serve to preserve the artifacts within.

A constant environment is the first means of preservation.  In addition to temperature, fluctuations of relative humidity (which lead to continual dimensional changes), can damage both organic and inorganic substances.  Recent research has found that it is more important to maintain constant relative humidity than it is to maintain constant temperature.  A material's dimensions respond to the relative moisture content in the air rather than to the absolute temperature.

The downside to this is that the environment might not be the most comfortable for humans. It is slightly chilling in the winter and warmer in the summer, such that the relative humidity remains stable.

The graph above compares the range of indoor and outdoor temperatures throughout the year with the corresponding relative humidity (RH).  Without heating, the relative humidity stays within the range limits of a safe environment. This graph represents southern New York State, but can be representative of the Northeast and many other similar areas in the country.

Below, various climates are plotted onto a hydrothermograph.  The cross hatched region represents the human comfort zone in both summer and winter with the ideal environment for artifacts highlighted in the orange area.  This is a visual representation to show how these areas intersect, but also diverge.

Why write about this now?  Because this time of year just happens to be the exception. The ground might be muddy, but actually the trees and other plants are doing their utmost best to absorb all of that extra moisture and then some, all in order to leaf out.  In the Northeast US, where there is a great deciduous forest, the evaporation climate goes from that of the Sahara to that of the Amazon Forest over the period of leaf emergence, which is sometimes as short a period as two weeks. Hence, it is the driest time of the year.

To see a wonderful animation of Spring making its way north along the east coast of the United States, please visit: http://sequoia.asrc.cestm.albany.edu/jrgroup/ Choose "Spring!" from the left margin, and then click on the first animation - the maximum temperature.

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Gwen Spicer is a textile conservator in private practice.  Spicer Art Conservation specializes in textile conservation, object conservation, and the conservation of works on paper.  Gwen's innovative treatment and mounting of flags and textiles is unrivaled.   To contact her, please visit her website.

Preparing and packing artifacts for shipment

"Have artifacts. . . will travel"

By Gwen Spicer

Any time an artifact travels, there is a great deal of risk.  However, travel they must.  Especially since part of the mission for a museum is education and displaying the artifacts to the public, and sometimes the public is far away, perhaps even on another continent.  Such is the case with collections from several New York State institutions that are traveling to Germany for the exhibit: On the Trail of the Iroquois, to open in Bonn, Germany later this year. This is an opportunity for a broader audience to see these amazing artifacts.

Spicer Art Conservation has been fortunate to be part of this great exhibition.  Several former posts have discussed some of the artifacts that are included in this exhibit.  But this particular post is less about the content of the exhibit, and more about the logistics of getting rare, unique and exceptionally delicate artifacts packed up, put on an airplane, and ultimately delivered to the other side of the world.  And then of course displayed before being packed up and flown back home.

The important part of such an endeavor is for all of the artifacts to safely arrive and then return. That is where the experience of Professional Art Packers and craters come into place.

First the individual artifacts need to be carefully supported. Then they and their supports need to be boxed and placed into sturdy creates.  It is a mathematical and geometrical problem that needs to be worked out in three-dimensions.  It also must be performed so that all the parts can be easily understood.  Standard systems have been worked out over the years by specialized Art Packing companies.  However, since each artifact is so individual, there is also a lot of custom work that is necessary.

Below are a few examples of such packing techniques that were designed by professional art packers.

One type of packing is called cavity packing.  It consists of foam that is carved slightly larger than the size of the artifact, the cavity is lined with polyester batting and covered with a layer of soft Tyvek.  The foam fills the inside of a box, and several boxes fill a create.  The individual artifacts are arranged to fit a specific area.

The small artifacts were kept in place with small pillows attached to twill tape.

Cavity packing of a larger artifact.

Larger three dimensional artifacts are boxed.  Below are several stages of a support for a basket.  The box is made of Gatorboard.  Both the base that the basket sits upon, and the support mid-way up, slide out.

Basket being fitted.

Internal support for the basket.

Below is the inside of a box for a ceramic pot.  The pot is secured and surrounded with the same materials and methods as Cavity packing.

The pots rests on a cushion and is secured with two halves that surround the neck
of the pot. The front sides pulls out, using the tabs. The pot can be safely removed.

The smaller boxes fit inside of this create.  The larger box is for the basket and the two smaller boxes are for two ceramic pots.

Create with the boxes installed.

The vertical box behind is only to fill the space.

As you can begin to see, the artifacts are grouped by their needs, shapes and sizes.  For this group of artifacts, size was a determining factor, as well as weight.  One long crate was created for all of the long artifacts that included javelins, arrows, and a pestle.  The storage trays for each of these artifacts were incorporated into the packing.  Some additional supports were added.  The heaviest item, in this case the pestle, was positioned as the bottom tray.  The vertical Ethafoam sides of the tray supported the tray to be placed on top.

Detail of buckle support.

Each tray's height was pre-determined.  So, when all of the trays were placed inside the crate and the lid is closed, all of the inside layers are precisely stacked and supported without too much pressure, but also not loose, for that would cause additional vibrations.

The Cane and Blow gun.

Another crate was sized for two larger artifacts, one being an overdress.  Other mid-sized artifacts were groups to fill additional trays.

The Ethafoam frame work is incorporated in the design to
support the upper trays when placed in the crate.

Individual bumpers were secured to the underside of the straps
that secured the mounted Snowshoes.

Straps were not used with this artifact, instead an Ethafoam
beam was  used to provided overall gentle pressure. 

A Volara layer was secured to outer surfaces of the Ethafoam bumpers.

Archival packing and crating is a geometric three-dimensional puzzle.  The individual packing occurs on site, but before the professional art packers arrive, there is extensive work that is done first.  A full plan is mapped out where all of the artifacts are to go.  Each tray and the amount of space is predetermined and pre-cut Ethafoam pieces are provided that are pre-sized.

It is critical that an institution provides as many accurate dimensions as possible. The dimensions must include not just the standard, height and width, but also depth.  If storage trays or other supports are present, these too need to be disclosed.  No company that is being asked to perform this task can know the size of these, and communicating as much as possible is necessary.

So many steps exist prior to an exhibit opening.  The orchestration of borrowing artifacts from several institutions, and then conserving, conditioning and packing these artifacts will be for nothing if they are not transported with the utmost care by the experts.

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Gwen Spicer is a textile conservator in private practice.  Spicer Art Conservation specializes in textile conservation, object conservation, and the conservation of works on paper.  Gwen's innovative treatment and mounting of flags and textiles is unrivaled.   To contact her, please visit her website.

The conservation of a McClellan Saddle, and a custom mount

by Gwen Spicer

Recently a Civil War era saddle came into the studio. A McClellan saddle, in fact.

Designed by George B McClellan (1826-1885) a career Army officer in the US Army. It remained in continuous use from 1859 to WWII, and is still in use by ceremonial mounted US Army units today.

There is some conflicting understanding of where the design originated, but many historians feel that it was based on the Spanish tree saddles, used in Mexico and in some parts of the US.  McClellan proposed the design after he spent one year with a military commission studying European tactics, weaponry and logistics.  Upon his return he produced a manual for the American cavalry, in this manual he proposed the design for his saddle.  Its importantance was that it was simple, less expensive to make than the current saddles of the times, it was lightweight so as not to further burden the horse, and well-made so the rider and gear were supported.  Simple meant less parts, which meant the saddle would be easier to fix in the field.  The light weight meant not only less for the horse to carry, but also easier on the horse so as not to cause saddle sores.

The original design had a rawhide-covered, open seat, leather skirt and wooden stirrups.  Our example is below.

McClellan saddle c. 1860 on custom mount

Saddles are complex artifacts with a mixture of sturdy parts and attached, more vulnerable, elements. It is this mixture of elements that complicate their display and storage.  They are also very heavy and quite awkward to handle, really requiring more than one set of hands.

As artifacts, they seem sturdy and robust upon first inspection, but in reality saddles can be awkward and vulnerable to damage.  The saddles that SAC sees have some historic significance.  They were used in battle and they saw hard, extensive use.  Of these saddles, the leather is usually quite warn from their heavy use, and it is distorted and weakened with age. These leather elements, which are the weakest, are often also the elements that are the most vulnerable, yet are still responsible for supporting heavier elements like stirrups or buckles.  It is no surprise that these often need to be reinforced.  

Over the years SAC has treated several saddles from a range of time periods and styles. The supports created for these saddles were based on a range of solutions directed by the institutions needs, and what could be adapted. 

For this particular saddle (that is quite complete and includes a leather girth strap), a commercially produced  metal saddle stand was purchased and adapted to meet the needs of the museum.  

Metal stand with strapping added.

Detailed image of the custom strapping created for the saddle stand.

The webbing was then covered with  polyester batting and cotton muslin. Polyethylene foam was secure below to widen the width of the stand slightly. A decorative saddle blanket could be placed under the saddle for display aesthetic and interpretation.

Ethafoam tied on with twill tape to make the stand wider.

The webbing supports the stirrups and fenders.  

Storage of this type of collection is a challenge. I must confess that I am a storage junkie, and I love to see the way storage of objects like saddles is approached.  The difficult task is to accommodate not only their size, but shape and weight.  Below are a few solutions that I have seen in museums during my travels. I include them as ideas for others.  Especially those who might be tackling the storage of complex artifacts. 

A simple solution is a fixed rod that is padded and supports the saddle with sufficient space below. The leather straps are relaxed as that the stirrups rest on the shelf below.  

A pair of padded metal rods span the length of the storage unit.

The height of the rods are so that the stirrups
can rest on the shelf below.

Another solution are the use of wall mounted supports with the saddles stacked on the wall.

Notice however with some of the above storage/display, the saddle is supported, however the stirrups and girth (the "belt" that goes under the horse and attaches on both sides of the saddle) are often left to hang free, causing some form of stress on the straps or buckles.  The Smithsonian has a McClellan saddle at the National Museum of American History and the Museum of the Confederacy has one in their vaults.  These saddles are not currently on display.  I don't know about you, but I cannot help but wonder how they are being stored.

Interestingly, some McClellan saddles on display at various museums are "new in box".  How is this possible?  Apparently the McClellan's that were manufactured circa 1904 were over ordered, this resulting in several that remained in storage in Army warehouses completely unused.

If you want to know more about the prolific use of the McClellan saddle read Wikipedia's article here: http://en.wikipedia.org/wiki/McClellan_saddle.  Or simply look up "McClellan Saddle" on your favorite search engine.

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Gwen Spicer is a textile conservator in private practice.  Spicer Art Conservation specializes in textile conservation, object conservation, and the conservation of works on paper.  Gwen's innovative treatment and mounting of flags and textiles is unrivaled.   To contact her, please visit her website.