Rehousing Sulka Masks

As a graduate student from the Buffalo State College Art Conservation Department, I am completing my summer internship at the Field Museum. I’m working in the Regenstein Conservation Lab with J.P. Brown, the Regenstein Conservator for Pacific Anthropology.  Our main project for the summer has been rehousing the Field Museum’s collection of Sulka dance masks from New Britain, Papua New Guinea. 

© The Field Museum, A111293, Photographer John Weinstein and Diane Alexander White .

The construction and dancing of the masks is an essential component of many ceremonies within the Sulka culture. The masks are made by initiated Sulka men in special mask houses over a period of months, danced by appointed men at the ceremony, and then are deliberately destroyed shortly after the ceremony.  The manifestation of spirit which the danced mask embodies is a significant event which is meant to be fleeting.  However, some masks have made their way into museum collections. The majority of the Sulka masks at the Field Museum were collected between 1909 and 1913.  The photograph below is from the Field Museum photo archives and dates from 1910.  It shows two men wearing Sulka masks; the mask on the left was rehoused during this project.

© The Field Museum, CSA33576, Photographer A.B. Lewis.

The masks range from five to ten feet in length and are constructed mainly of plant materials including pith, spathe, withies, leaves, and fiber cordage. These materials are woven together to create hollow basketry elements which are lashed to a central wooden pole.  The masks are decorated with colorful designs using various mineral and organic pigments; the bright red colorant is said to be plant pollen.
 

Composite x-radiograph of Sulka mask.

While some of the Sulka masks in the Field Museum collection are on display in the Pacific Spirits Gallery, the majority are in storage.  These masks were stored hung from metal conduit with cheesecloth loops and wrapped in polythene sheet.  Although this storage system has been generally successful in preventing gross physical damage to the masks, it has been unsatisfactory in a number of ways: the polythene sheet was hard to remove and replace without damage to the masks, contact with the draped polythene sheet has led to brittle fiber breaking away from the dried grass "ruffs" at the bottom of some of the masks, the masks tended to swing and bump when being moved, and the loops of cheesecloth fabric prevented overall examination and photography of the masks and are abrasive enough to remove the red pollen pigment at points of contact.  The aim of the rehousing project was to create a safer housing system – one which would allow the masks to be readily visible in storage and more easily accessible for detailed study.

Sulka mask photographed in the lab before rehousing. 

Rehousing a mask begins with building a fitted cradle for the mask from aluminum tubing connected to plywood slides with slip-on fittings.  The mask is supported at key locations with sewn Tyvek slings, shaped with inserts of polyester batting or polythene tri-rod, and covered with silicone-coated polyester film to prevent pigment transfer.  The hang of the slings is adjusted for best fit by modifying the length of the twill tape ties which connect the slings to hexagonal-headed self-tapping bolts screwed into the cradle arms.  A special sling is made from of 0.75 mil polyester sheet to support and contain the dried grass ruff at the bottom end of the mask.

 Above and below are views of the Sulka mask supported by slings in its cradle.

The next stage is to create a physical barrier around the object to prevent bumps and dust accumulation, and to contain any material that may detach from the mask.  The method used here was adapted from a method developed by Field Museum Assistant Conservator Hildegard Heine in 2005.  Structural aluminum framing is cut to length and joined with friction-grip fittings to create the framework for a storage box.  A dead-blow mallet is used to pound everything together and proved to be a great stress reliever.  One inch magnetic strip is then adhered around one of the long sides of the frame as an attachment for an access flap.

 Constructing the aluminum frame with Conservation Assistant Sophie Hammond-Hagman.

3/8" plywood is cut to form the base of the fame, and then one long side, two short sides, and the top of the frame are covered with clear polyester sheet.  This is when the electric drill and driver come in handy – lots of screws are used to hold everything in place.

The pieces of polyester sheet are lapped so that, if water falls on the housing, it will be shed to the floor rather than working its way inside the housing.  The polyester has much better clarity than polythene sheet and allows most details of the mask to be seen without removing the mask from its housing.  The access flap on the long side is made of fiber-reinforced low density polyethylene.  A magnetic strip is heat-sealed into three edges so that the flap mates with the aluminum frame and can easily be opened and closed.
 

 Conservator J.P. Brown with a completed storage box.

Finally the Sulka mask, on its cradle, is slid into the new storage mount.

The rehoused mask is moved to its new home in the Field Museum's Collections Resource Center.

The masks are now much better supported and protected.  With less movement possible within the storage mounts, there is less risk of damage to the objects.  The masks can also be viewed and accessed much more easily - not only can they be seen within their storage mounts, but they can also be removed for detailed examination without directly handling the object.  The back flap opens, the stretcher slides out, and the wooden ends of the stretcher can rest on a table, allowing for easy access to all sides of the mask for research.  So, all of those power tools were necessary.  The new Sulka mask storage mounts look fancy and are functional, too!