“A great deal however depends on the individual in the field, his good judgement, his diagnosis on the condition of the specimen and just how it should be handled, the character of the material he has to treat, how much time is available and its reaction to certain kinds of treatment.”
-Louis Schellbach to J. Alden Mason, December 27, 1939
On December 27th, Louis Schellbach, who had accompanied Samuel K. Lothrop to Sitio Conte, replied to Mason’s inquiry of the 23rd of December with a six-page response. The letter details what conservation methods he used previously and offered his advice about conserving specimens in the field. His extensive notes outline what our Head Conservator Lynn Grant, calls “a very inventive approach” to on-site specimen conservation with his use of gum arabic. Schellbach writes:
Most material in these sites will be found in damp or wet condition and near the water table they of course will be saturated. This will be due to the periodic flooding of the area during the rains.
The best first aid is to make all parts of the specimen hold together by hardening it in situ for removal.
This is done with a solution of gum arabic, not ambroid or celluloid solutions, they have no affinity with moisture. Gum arabic dissolved in water makes an adhesive of any consistency which will soak into wet objects and when dry holds all together. Apply a fairly thin solution of this gum arabic to the object, either with a pipett or a soft camels hair brush. Allow the solution to soak in and then apply another coat . Allow all to dry slowly in the shade and when hard remove the object and wrap carefully in tissue or toilet paper and set aside for special packing. This treatment holds the specimen together by entering all parts and when dry holds all parts together in place without checking or splitting.
Lynn, who worked on the conservation of some of these same objects during a previous exhibition of the Sitio Conte collection, believes that Schellbach’s method “probably saved many artifacts that would not have survived” after being exposed during the dig.
What made the conditions at Sitio Conte so delicate and required that Mason “tak[e] a man especially for this work”? The geography and wet climate of the area were the main issues that the archaeologists faced. The site of Sitio Conte, situated on a flat coastal plain on the Isthmus of Panama, was discovered when at the turn of the century the Río Grande de Coclé changed course and revealed a pre-Columbian cemetery. Pieces of pottery and gold washed out of the river banks and the locals began gathering up the found objects, with some of them ending up for sale in Panama City.
These are the wet and humid conditions that Schellenbach and Lothrop worked in, and the same conditions that Mason and his team would encounter. Check back next week for our third installment.
Read the first post in this series “Sitio Conte in Real Time: December 23, 1939“