It’s tempting to try and specify the kind of brown ink that’s been used in the making of an old master drawing. Iron-gall (black, but changes to brown over time) and bister were the two most commonly used inks. Sometimes, people will refer to any brown ink old master drawing as being in sepia. Maybe it’s because they’re so used to hearing that everything is made from petroleum, that the idea of ink coming from a sea creature is quaint and charming. Maybe it has to do with the 19th c. sepia drawings and the chemical approximation of sepia in 19th century photographs. (The continuing appeal of sepia coloration is clear from the photography edit for “sepia effect” on the computer or cellphone.) Instead, sepia was rarely used before the late 18th century.
Sepia (also called cuttlefish), as well as octopus and squid, are soft-bodied mollusks, known as cephalopods (cephalo-head/pod-foot). Most cephalopods produce a dark fluid that they can expel to hide themselves from predators. Its primary component is melanin, related to the pigment that colors our skin and hair. Aristotle, whose accuracy and method continues to surprise biologists, said of the cephalopod ink sac, “All the Cephalopods have this peculiar part but it is the most remarkable in the Sepia, as well as the largest in size. When the Sepia is frightened and in terror, it produces this blackness and muddiness in the water, as it were a shield held in front of the body.” [Aristotle, The History of Animals, Book IV. The translation comes from A.L. Peck & E.S. Forster. Aristotle XII: Parts of Animals Movement of Animals, Progression of Animals, 1937.)
Sepia (sepia officinalis), then, have more ink than other cephalopods. They have eight legs or arms, two tentacles, and are about ten inches long. Just below is a depiction of a cuttlefish from a Pompeian mural.
Because the mural is more pleasing than accurate, here is a scientific diagram of a cuttlefish.
Aristotle does not say that sepia fluid was used for writing, but there are Roman writers such as Cicero, who did. This link carries to the entry on atramentum, the Latin word for ink, in A Dictionary of Greek and Roman Antiquities (1875), where passages of ancient writers are cited and linked to.
At its simplest, the ink can be used directly from the cephalopod, mixed with a binder. This is probably what the Romans did. The ink may have developed a bad smell, but their tolerance was greater than ours (think of garum, the fermented fish guts they ate, and loved). Sepia is known to be fugitive, and as far as I can tell, no ancient papyri with sepia ink exist.
James Watrous, in his 1957 The Craft of Old-Master Drawings, noted the “powerful fishy odor” of the dried sepia chips and sepia splinters, that he found imported into the US from Italy (1975 edition, 88). Zecchi, the art supply shop in Florence that specializes in old master materials, sells sepia pigment (10 grams for 24 euros and 100 grams for 200 euros) and maybe in the intervening 50+ years since Watrous was writing, a way of deodorizing sepia has been developed. The cost would warrant it.
Zecchi was founded in the 1950s with the idea of furnishing the materials that the 14th century Cennino Cennini details in his Libro dell’Arte. Cennini does not discuss sepia at all. In fact, the expert writers on the subject of old master materials–Joseph Meder, James Watrous, and Carlo James and company–say that sepia ink was hardly used, and written about, before the late 18th or early 19th centuries. Courtesy Google Ngram, here’s a graph of phrases with the word sepia, found in English language books, between 1800 and 2008, which shows that “sepia drawing” was most used around 1910. This takes into account novels, and everything else, so it has to be taken lightly.
Natural sepia drawings are supposed to have a cool, rather than warm, brown color, and a purplish or red cast. It’s known that Caspar David Friedrich (1774-1840) drew with sepia ink. Just below is a Friedrich drawing at the Albertina, and the image is taken from the Google Cultural Institute. We can assume that they’ve taken some care in getting the color right. The Albertina describes the drawing as being in brown ink. The tendency in museum catalogues, and in museum databases, is to move away from describing the type/origin of ink, and describe it generically as brown ink. This makes a lot of sense, because you can’t get it wrong. However, because of Friedrich’s known use of sepia, and the color of this drawing, it would seem to me that it is in sepia.
Scrutinizing and testing every drawing in collections, where there are thousands of sheets, would be an enormous undertaking, and the preference for simple “brown ink” is easily understood. The fact that artists very often combined different types of inks and pigments, makes specificity even more complicated, and less documentable.
However, if one were curious enough, and were able to commission work from a lab, there is a test for sepia ink, which its developers describe as rapid and simple. The 2009 study is entitled Characterization of sepia ink in ancient graphic documents by capillary electrophoresis and is available as a pdf here. Ana López-Montes, Rosario Blanco and others, studied maps and drawings in Granada’s Royal Chancellery Archives. The earliest map was from 1570 and the latest from 1817. Since the maps and drawings related to court cases, as exhibits, the dating is precise. The study is interesting also because its writers discuss taking the ink sac from a cuttlefish, being careful that too much air didn’t come in contact with the ink, and mixing it with gum arabic and water.
Carlo James, Marjorie B. Cohn, and the other authors of the 1997 Old master prints and drawings: a guide to preservation and conservation, spoke of Genova and Venice as being two places where sepia ink was used, before the 19th century. While Granada isn’t on the coast, it isn’t far, at about 20 miles. So, maybe one should keep an open mind about whether old master drawings, and especially those made near the sea, are made with sepia. (You can think sepia, just don’t write it. Plain vanilla. Brown ink. Basta.)