Fol 46v: Oil of Sulfur for the Writer, Aftermath

Upon checking back on the reconstructions 2 weeks later, the sulfuric acid had corroded the parchment (both goat and calf) for the Trial 2 experiments, but not the paper. For the Trial 1 experiments, it had corroded the calf and partially corroded the goat.

Fol. 46v: Oil of Sulfur for the Writer, Trial 2

Olivia Clemens
Lab Supervisor: Joel
Date: 2016.04.29

Since the previous experiment with 15% sulfuric acid was inconclusive, we decided to repeat the two unsuccessful experiments with a concentrated sulfuric acid solution. Luckily Joseph Ulichny was able to provide 96% 15 Molar sulfuric acid for the second round of experiments, which meant that I did not need to concentrate the 15% sulfuric acid, which could have incurred health risks in the heating/evaporation process.

The second round of experiments only needed to test two recipes: "erasing a letter" and "oil of sulfur for the writer," both from fol. 46v.

"Erasing a Letter" -- this experiment was repeated following all the protocols explained in Trial 1, only with the new concentration.

Observations: I was expecting a dramatic result when the sulfuric acid was applied to the paper/parchment, and was actually a little surprised that the reaction was more gradual. The letters did not totally disappear -- they turned pinkish and faded. This was most effective in areas with larger amounts of the solution, such as the middle of a piece of parchment that had naturally started to curl inward, allowing the solution to pool in the middle a bit. It also seemed to be most effective with Ink # 2 (cold prepared iron gall ink) but that also could have been because Ink # 2 was in the middle of the samples where the acid poole the most. The reaction with iron gall ink was definitely noticeable in comparison with the furnace black/carbon ink, but the letters did not vanish completely. It is, however, possible that further actions (like washing the parchment/paper) would have removed the ink more fully.



"Oil of sulfur for a writer"

This was very effective. The ink came off the quill very cleanly in this experiment. In trial 1, the sulfuric acid solution was no more effective than water at removing ink (in both cases the quill remained blackened) but in Trial 2 the quill came out very clean.



Conclusions: A higher concentration of sulfuric acid was effective with "Erasing a letter" and "Oil of Sulfur for the Writer," though the ink was not totally removed from the paper/parchment with "erasing a letter."

Fol. 46v: Oil of Sulfur for the Writer, Trial 1

Olivia Clemens
Lab Supervisors/Collaborators: Joel, Jenny
Date: 2016.04.22
Time: 10:20am-2:00pm

I began with prep:
Step 0: Cleared out the fume hood, moving all contents to the other fume hood. Also received a quick fire extinguisher training and moved the fire blanket nearby!




First, I began by heating a small amount of sand (about ½ cup) in a small pan on the hot plate in the fume hood in order to temper the quills. I used an IR thermometer to measure the temperature of the sand as it was heating, checking on it periodically.



While the sand was heating, I cut paper and parchment pieces into small squares and labeling with pencil for each trial. For Experiment 1, I used both goat and calf parchment, and paper (50-50 hemp & cotton, with gelatin sizing), and divided each piece into three columns: iron gall ink 1 (the recipe I made), iron gall ink 2 (from 2015 paleography workshop), and carbon ink (“furnace black”).



For experiments 2 and 3, I also cut three sample pieces to size, both goat and calf parchment and paper. I would be writing directly onto these with the sulfuric acid solution, so I did not need to label these other than to denote the type of material on each (e.g. goat, calf, paper).

I also fashioned a “sponge” by taping cheesecloth to the end of a chopstick.

After the sand had heated to about 550 degrees, I made my first attempt at tempering the quills. This was much too hot and blistered/melted the quill. I then allowed the sand to cool down to about 200 degrees in the fume hood and tried again. This temperature didn’t seem to have much effect on the quill. The Scriptorium tutorial I had looked at recommended 350 degrees, so I reheated the sand until it reached 350 and tried again. This produced a hardened quill that did not blister or melt.


Melted quill!


Successful tempered quill!

Now that my basic prep was done, I gathered my materials and could proceed to the experiments. For Experiment 1, I was writing with various inks onto different parchment/paper samples, and then tracing over these letters with the solution. The goal of the recipe was to erase the inks with the sulfuric acid. I began this experiment by first prepping my sample squares of parchment and paper by writing on them with the different ink samples and waiting a minute for these to dry, blotting excess ink. Already, I noted a variable: each of the inks I was using wrote differently, as did the different quills I used for each ink. The furnace black was the thickest and most difficult to write with, whereas Iron Gall Ink 2 was quite runny. Iron gall ink 1 wrote most easily, though this may also have been a factor of the quill I used for it being the best cut. After I had prepared these samples, I could move into the fume hood and begin working with the sulfuric acid.




I poured a small amount of sulfuric acid into a dry, glass beaker in the fume hood (first laying down paper towels), and used a fresh quill that would be used exclusively with the sulfuric acid solution.




Trial 1
First application: it was difficult to trace the ink letters with the sulfuric acid since the sulfuric acid solution was quite watery, so decided to just apply broadly sulfuric acid over written letters.
There was no visible change on first application of sulfuric acid. I retraced some of the letters, and the solution did seem to dilute the letters, but I suspected that this was due to the water in the solution dissolving the inks rather than the sulfuric acid. We therefore decided to add a water control to compare the fading of the sulphuric acid solution to a treatment just with water.



Next I tried to my second variation -- seeing if wet ink would react differently from dry ink. Again, the solution seemed only to dilute the letters.


Next we tried the control with water (using a different quill prepared by Marc Smith that we did not temper -- unsure whether it had previously been tempered). I observed no difference between sulfuric acid solution and water.


Of course, it is possible that as water evaporates from the solution over time the sulfuric acid concentration will become stronger and work more effectively. This will require observation.



Experiment 4:


I had planned to do this experiment last, but since we were ready to put the ink away to move onto Experiments 2 and 3, which just involved sulfuric acid on paper/parchment, we decided to reverse the order and move onto cleaning the quill. When iron gal ink 1 was immersed in the solution, particles came off, but it did not turn “immediately clean and white”. This seems to indicate that the solution is not strong enough. (Cleaning the quills used with other inks in the solution seemed equally ineffectual, or at least no more effective than cleaning in water.)



Experiments 2 & 3:


These experiments involved writing onto different materials with sulfuric acid and heating to see if a color change would take place. Though recipe 2 does not specifically say “paper”, recipe 3 does specify paper; this corresponds with the idea that cellulose would react with sulfuric acid in a way that parchment would not. We therefore expected the paper to change color but not the parchment.


Because it was difficult to see what we were writing with the sulfuric acid and we wanted mainly to get proof of concept, we decided to draw circles onto the different materials rather than try to write. Additionally, since we were wondering about the concentration of the sulfuric acid and whether it would affect these experiments, we decided to make three trials on each material: a circle that I went over with the solution once, a circle that I went over twice, and a circle that I went over thrice. I labeled these trials with pencil.



Trial 1:


[12:40pm] We started with goat parchment, holding it over the hot plate with tongs. The hot plate was at a temp of 715, the parchment itself at 150. No color change occurred, but the parchment began to warp. The same thing happened when we repeated the experiment with the calf parchment -- even at high heat, no color change occurred, but the parchment curled and warped. This supported the idea that parchment would not be used in such a process -- not only would it not react with sulfuric acid in the same way as paper, but heating parchment ruins it, whereas paper can be heated without adverse effect.


Next we tried paper paper:


At about 380F (temp of paper, not hot plate) the different dots 1 layer, 2 layers 3 layers turn black, with no difference between three dots visible. The low concentration of sulfuric acid was thus effective on paper. (See video.) Is this because less sulfuric acid was needed for this experiment, or because as sulfuric acid is heated it concentrates with evaporation?





Experiment 3:


This was really an extension of Experiment 2 -- I “sponged” the black letters on the paper with the cheesecloth-on-chopstick implement. After a while the black dots fell out of the paper, which provided proof of concept. Though this “a jour” technique seems like it would be very hard to control, it does seem possible.




Cleanup:


This concluded the experiments for the day. We cleaned up very carefully, disposing of the liquid sulfuric acid solution in the new labeled sulfuric acid liquid waste bin and the solids in a new labeled sulfuric acid solid waste bin (gloves, paper towels, etc). We saved the parchment and paper trials in labeled plastic baggies in the fume hood.


After cleanup, we transferred the things we had moved into the other fume hood back to the fume hood we used.


Reflections:

I was happy that the diluted sulfuric acid solution was effective in experiments 2 and 3. Unfortunately it didn’t seem strong enough to work for cleaning the quill or removing ink from parchment/paper. I hope to retry those experiments with a stronger solution by concentrating the existing sulfuric acid through a process of evaporation.