The manuscript charts in this atlas were made in 1620 or 1621, probably by Gabriel Tatton, an English chartmaker, and probably on board the ship Elizabeth during a voyage to the East Indies. According to an article by Sarah Tyacke ("Gabriel Tatton's Maritime Atlas of the East Indies, 1620-1621: Portsmouth Royal Naval Museum, Admiralty Library Manuscript, MSS 352," Imago Mundi, vol. 60, Part I: 39-62) it is likely "the sole surviving example of an original English marine surveying in the East Indies in the first half of the seventeenth century." I'll leave it to her article to tell the history of its making and influence. What I can tell you is it's a good case of "don't judge a book by its cover."

Sometime between 1779 and 1800 the unbound charts were acquired by Alexander Dalrymple's Hydrographic Office The charts were bound in the late 18th century, at which point the Hydgrophic Office added a paper title page and index to the front, both of which survive (the title page is shown above right), along with a single white folio at the back of the binding; presumably these were part of the end sections in that binding. At this point someone also numbered the charts 1 to 17 on the verso (head fore-edge corner) in carbon black ink.The leaves are parchment, with the charts in black, warm red, cool red, green, blue, and yellow inks. In the 18th century binding it was guarded on parchment (two small scraps remained) with animal glue that remained in thick stripes along the spine edges of the bifolia. I could find no evidence, however, of the original endleaf construction nor binding style: sewing stations would be in the now-lost parchment guards, and the paper flyleaves no longer had spine folds. Contemporary atlases tend to have suffered rebinding, whether out of necessity or aesthetics (why have a tatty 18th century binding when you can have a nice new 20th century one?), so searches for something similar in its original condition turned up nothing. I would guess it might have been full leather or full parchment with little or no decoration.A binding ticket on the rear pastedown for "Eyre & Spottiswode, Bookbinders, East Harding St. London" indicates to me that the rebinding that you see here was done between 1832 and 1875, when the firm was at that address, probably to the later end of that range given the binding style. It's a half leather tightback binding with brown calf and a textured purple paper on the sides, with the leaves guarded on paper and sewn on 8 raised double cords. Minimal tooling on the spine (single palettes on either side of the bands, titled in the third panel on a black label and stamped with the Admiralty mark in the tail panel). The endbands were originally sewn in pink and white silk, but after these presumably failed they were replaced with red and yellow machine-made bands over cane cores. Probably at this time the spine lining was also reinforced with a starched white fabric in several of the panels, which didn't keep the binding from falling apart for long:

In the image above you can see that the cords have almost completely disintegrated: when I touched them with a spatula, they crumbled under its tip. The leather here is about pH 4. Although the attachment guards were reasonably flexible, they'd lost almost all of their spine folds, meaning extensive repair. The compensation guards were quite wide, which meant the leaves did not open as well as they could have and that the movement of the attachment guards was restricted, having less space to move.

The endpapers were tipped on to the original paper leaves at the spine edge, resulting in a completely inflexible spine edge along which all three leaves were cracking, along with the attachment guard of the first chart. This is a good example of what happens to degraded paper when part of it is held more stiff than the rest, whether from glue or tape or some other restriction: it will fail along the edge where the flexibilities are different.

Above, remnants of the endband original to this binding. The hole in the parchment that you see at bottom right is one of several throughout the atlas; it is the result of a scar in the skin before it was made into parchment, an area of lesser flexibility and stretch that, when the skin is put under tension and scraped, results in a hole.

This image of opening between two of the parchment leaves (with paper guards in the center) shows the history of the binding and rebinding: the white stripe you see to the left of center is a wide stripe of abrasion that continues to the other side. This was definitely done after the image was made, and after the parchment was folded for binding, because where the pigment underneath is thicker, the skin was abraded more and actually bears the image of the pigment, just like a crayon rubbing of a gravestone. The dark brownish-yellow is the animal glue from the first binding, which was not removed for the rebinding. In the first binding, the guards were attached on the recto or the verso of each bifolio, with no apparent pattern; in the rebinding, they were only attached on the recto, so this glue was only visible on some of the bifolia prior to disbinding.
Because the extant materials were in poor condition and not the originals, and because the contents of this binding are so important, I decided to disbind the volume and rebind it with new, sympathetic materials that would better protect the charts. The first step was to remove all of the old guards and adhesive residue: the former was easy; the guards were mechanically torn off and the leftover paper thinned with a scalpel. The rebinding adhesive turned out to be a thin, slightly opaque white adhesive that I didn't identify and could have been one of several things. It responded to moisture, as did the animal glue, so with blotter inside the bifolia, once the adhesive was mechanically removed as much as possible, I used minimal poulticing with sodium carboxymethyl cellulose (SCMC) to take up the rest. I found that if the gel stayed on more than a few seconds, the red pigment offset slightly on the blotter---and upon closer inspection I could see that it had offset in the gutter of some bifolia during the previous rebinding as well, leaving a ghost impression on the other side of the fold. This made me wary of using more tradition water-based adhesives like gelatin, isinglass, or wheat paste to adhere new guards, but I'll talk about that more later.

Above: the guards, stuck-on endbands, threads from sewn endbands, and sewing threads saved from the disbinding.

The paper leaves were humidified through GoreTex to remove them from each other, then poulticed with SCMC to remove leftover adhesive. Losses in the paper were filled with new handmade western paper, and tears and weak areas were supported with thin Japanese kozo paper (the images above are in-progress, the losses in the fore-edge on the right-hand leaf are visible as brighter white spots, but the spine edges have not yet been repaired).

Above: the binding and endleaves

Above: the stack of 17 bifolia, ready for rebinding
Stay tuned for more... it'll take me much less time to write the posts than it did to do the conservation work!