There is a common misconception that history is drab, brown and yellowed—all sepia tones and dust— but this couldn't be farther from the truth. The 18th century was a spectacularly colorful time, where the confluence of an international trade in paint pigment and a broadening palate for evermore audacious color combinations conspired to make the 1700s a extremely colorful, if not garish, century.
In this post, I am going to give a quick digest of the story of paint and paintmaking in the 18th century, focusing at the end on how paint was relevant to the vehicular trades of wheelwrighting and coachbuilding.
Color Science
Throughout the 18th century, one sees a general push toward a more scientific approach to understanding the natural and physical world. Great import was placed on discovering what was at the heart of certain phenomena without recourse to magic or theology—the Age of Enlightenment. This is evidenced in the attempt by numerous authors to spell out a science of color. How does color work, mechanically? What is the human eye capable of discerning? What colors harmonize, and which do not? Can a general systematic understanding of color be derived?
The first notable attempt at systematizing color is attributable to none other than Sir Isaac Newton, father of physics and calculus. Of course, he did numerous experiments in optics, looking closely at the mechanics behind the refraction of light through a prism. In his Philosophiae Naturalis Principia Mathematica, published in 1687, he offered the first instance of organizing color into a circular diagram, what we now call a color wheel. While Newton's aim was to describe the mathematical principles lurking beneath these phenomena, his color wheel caught on with other less ambitious authors as logical way to describe and present the relationship between various colors. Thus, the color wheel found its way into manuals and treatises on painting and paintmaking in the 18th century.
Another attempt to treat color systematically was made by German astronomer Tobias Mayer, who delivered a lecture on his color system in 1758 in Gottingen. Rather than focus on the mechanics of light, however, Mayer was more interested in the artisan's approach to generating various hues and the limitations of the human eye to discern differences in mixed colors. Mayer organized his theory around a triangle instead of a circle, and looked closely at the relationship between color and pigment, as opposed to pure light. Mayer posited that all possible colors were derived from mixing three primary colors—not a revolutionary insight—and that the human eye could only detect a 1/12 difference in any color formula. That is to say, if a recipe for a particular hue is broken up into 12 parts, then you can only generate a new recipe by changing at least 1 part of that recipe. For instance, suppose you mixed 6 parts red with 6 parts yellow. Then you would make a standard secondary orange color. If now you instead mixed 7 parts red with 5 parts yellow, you would still make an orange color, but one distinctly different from the previous recipe. This 1/12 threshold extends to using white and black pigments as well, which serve to either brighten or darken the hue's shade.
Colourman's Trade
Stepping away now from the theoretical view on color, we'll look now at the practical side of color, namely: Paint. Where was paint coming from? Who was making it?
In the 17th century the colourman's trade emerges as a specialization of the painter-stainer's trade. Colourmen are responsible for making paints to order as well as selling paintmaking supplies such as pigment, oil, and brushes.
The colourman's trade was well established by the 18th century. Numerous individuals and concerns billed themselves as colourmen, the specialty often growing out of first working in the house painting trade. One such London-based concern was established by Alexander Emerton in 1720. A selection of Emerton's palette was referenced in the Palladio Londonensis of 1734 along with the price per lbs for pre-mixed pigment.
Alexander Emerton's brother, Joseph Emerton, also started a colourman's concern shortly after Alexander's death. Seen below is Joseph's trade card. At the top can be seen a cartouche with a scene of an artist painting a portrait for a sitting model while, in the background, a horse-powered paint-grinding mill is in operation. Joseph Emerton was advertising the fact that he was grinding paint in volume to sell in his shop, using horse-power to scale his production! His was an industrial concern.
Colourmen sold more than just ready-made paint. They sold all the necessary accoutrements to making paint, including oils, brushes, and pigments. You can see a number of these supplies advertised in John Rich's trade card below which is of indeterminate date, but likely, based on style, from the 18th century.
How Paint is Made
So how is paint made? Simple! Aggresively mix dried pigment into boiled linseed oil and voila! You have paint! While it sounds simple, there are indeed finer points to making paint by hand, 18th century style. So, to make the topic more tangible, I've embedded a quick video demonstration of me making some paint in the wheelwright shop here at Colonial Williamsburg.
Ingredients
18th century oil paint consisted of three key ingredients: pigment, oil, and lead. I want to discuss each in turn, starting first with pigment.
Pigments
By the latter half of the 18th century, pigments were widely available, being collected and processed all over the world, and then shipped internationally to western markets, making it all the way to stores and colourman's shops in colonial America.Pigments were derived from a variety of the sources in the 18th century. There were earth-based pigments, pigments derived from minerals, pigments that were by-products of corrosive processes, and even the first lab-grown synthetic pigment! Below you'll see a large selection of pigments that could have been bought in a colourman's shop in the period.
Now, although raw linseed oil possesses a natural drying property thanks to its triglyceride content, it still dries very slowly. Oil paint is notoriously slow drying, which for fine arts application isn't an issue, but for house painting, ship painting, and vehicle painting, is a big bottleneck. So painters and colourmen discovered that they could process the oil in a special way to quicken its drying time by boiling lead into the oil. This new product gained the apt title of boiled linseed oil, and is still used to this very day for finishing raw wood or as a paint vehicle (see below for further discussion).
Earth-based Pigments: By far the most ancient of pigments, earth-based pigments were the colorants of the very early cave paintings, and even used in funerary rites among the peoples of antiquity. Ochre in all its variations was a very common pigment in the 18th century, partly because it was very abundant, inexpensive, and could often be sourced locally. Some common ochres we use in the shop are: french red orchre, french yellow ochre, spanish brown, and umber.
Mineral-based Pigments: Pigments derived from minerals were definitely more pricey than earth-based pigments, and thus found more application in a fine arts context, or with luxury objects. Needless to say, it was rare indeed for a cart or wagon to painted with a mineral-based pigment. Examples of such pigments are: vermillion which is derived from cinnabar, massicot, malachite, and lapis lazuli.
Pigments derived from corrosive processes: Numerous pigments come from corrosion of metals. In fact, the range of red colors seen in ochres often is a function of their iron oxide content, or in other words, how much rust is in the dirt! other examples of pigments derived from corrosive processes are verdigris (copper rust) and white lead (lead rust). Lampblack is a pigment made from the corrosion of wood by fire. That is to say, soot! Red lead, which I will talk of more later, is a what happens when you expose white lead or massicot/litharge to a heat treatment.
Synthetic Pigment: Little-known fact: the very first synthetic pigment was developed in 1706 by German painter Johann Diesbach. As the story goes, Diesbach was actually trying to come up with a commercially viable alternative to carmine, an expensive red dye derived from the cochineal beetle, when he happened happily upon Iron ferrocyanide, an incredibly strong blue pigment! Iron ferrocyanide quickly caught on as a much more affordable alternative to ultramarine, a strong blue pigment made by grinding lapis lazuli into a fine powder. In the trading circles, iron ferrocyanide began to be called "prussian blue", and the name stuck.
Linseed Oil
After the colorant, the "vehicle" of the paint is the next most important ingredient in any paint. Most oil paints made in the 18th century, especially in volume, were made using linseed-based oils. Linseeds, for those that aren't botanists, are the seeds of the flax plant—which we coincidentally also make linen out of, thus the name linseed. Actually, linseed oil serves two purposes in paint. It is both the vehicle, which is the substrate that carries the pigment, and the binder, the constituent that enables the paint to stick together and harden. It is the presence of a triglyceride in the linseed oil which, when exposed to oxygen, polymerizes with other neighboring triglycerides in the oil, forming a hard film—dry paint!
Linseed oil was made by means of a large edge runner mill (basically a large mortar and pestle), driven generally by animal-power, much like what was used to process apples for a cider press, or other botanical oils like olive oil. Below you can see a 17th century depiction of olive oil production, which is more or less identical to how linseed oil would have been produced in the 18th century. You see on the left an ox attached to an edge runner mill being driven around in a circle, while a man fills the "mortar" with freshly picked olives (read: linseeds). Once the edge runner mill has pulverized the olives, the mash is gathered into a permeable bag, and the oil is pressed out of the mash in a large vertical press as seen on the right, the screw being turned by three men at once. Once the oil is pressed out of the mash, it is filtered further and processed by boiling, loaded into casks, and taken to market.
Lead
I count lead as the third most important ingredient in 18th century paints. It makes its way into period paints through a number of avenues, as a drying/hardening agent, as a pigment, and as a biocide.Lead comes in three different flavors, at least in the context of paint: lead monoxide, lead carbonate, and a lead tetroxide. I talk about each in turn.
Lead Monoxide - Litharge - Massicot
Lead monoxide is the most basic form of lead found in period paints. It occurs naturally in a mineral form, and is used both as a pigment and a drying agent in oil paints. Lead monoxide takes on two distinct morphological expressions: litharge and massicot. Chemically, litharge and massicot are the same compound, but they differ in their crystal structure, which practically means that lead monoxide comes in two different colors: red (litharge) and yellow (massicot). Now, while both litharge and massicot were used as pigments, they would have been a rather expensive way to achieve a red or a yellow, and so were more often used as an additive in boiled linseed oil.
The way it worked was as follows: A relatively small amount of lead monoxide was added to raw linseed oil, then the mixture was boiled until reaching a thick syrupy consistency. The mixture was left to settle, and the clarified oil which settled on top was ladled off the top of the batch. This process removed impurities in the oil and enriched it with lead monoxide. The presence of the lead monoxide in the oil served as a catalyst toward polymerization of the triglyceride - that is to say, it helped the oil dry faster!
Lead Tetroxide - Red Lead - Minium
So if you take lead monoxide in either of its forms—litharge or massicot—and submit it to a heat treatment (calcination), it transforms into lead tetroxide, otherwise known as red lead. Red lead is a pigment in its own right, and is often used much in the same way lead monoxide is used, serving as an enrichment in boiled linseed oil. However, red lead is more toxic than lead monoxide, and so has greater utility as a biocide. Red lead paint was often used a primer, especially in areas where there was greater likelihood of rot or corrosion—the idea being that the greater toxicity of red lead would ward off from microbes and fungus that wanted to eat your house siding, or the bilge of your boat, or the undercarriage of your wagon. The microbe would get a mouthful of toxic paint and then die before it had a chance to do serious damage. In contexts where it didn't matter, the red lead paint was left exposed instead of being painted over with a more attractive color—red lead varies in color from a Pepto-Bismol pink to a caution-cone orange based on which starting ingredient was used, litharge or massicot. As we will see later, the undercarriage of wagons and carts was often painted red, not because it was more fashionable, but because the wagonbuilders were priming the undercarriage in red lead and often didn't feel compelled to cover it up with a more attractive color.
Lead Carbonate - White Lead
Yet another lead-based pigment in the period is white lead, which is ultimately derived from the corrosion (rust) that collects on metallic lead sheet.
White lead was big business in the 18th century. It was essentailly farmed and processed on a large scale. A technique was used known as the "stack process" to produce white lead in volume. The process required special "corroding pots" which held a small amount of vinegar at the bottom and had hanger-rod mounted above the pool of vinegar. A coil of metallic lead was suspended above the vinegar on said rod. The pots were then stacked over a layer of horse manure in a enclosed space. The combined action of the acid vapor, and the heat and carbon dioxide given off by the composting horse manure caused metallic lead to corrode, producing lead carbonate. The corrosion left a white crust on the coiled lead sheets that could be scraped off, pulverized, and subsequently used a white pigment.
Mechanization
As should be evident from the video of me making the small amount of paint by hand, the process is time-consuming and laborious. In order to produce pigment on a large scale, mechanization was a must.
One of the earliest examples of a "mechanization" dates to c. 1700 and is attributed to Thomas Child, a Boston-based colorman. His system for grinding used a large stone sphere and a corresponding stone trough - sort of like a large pestle and mortar. The stone sphere was pushed back and forth in the trough with the paint ingredients placed at the bottom of the trough. While certainly laborious, Child's system produced much larger quantities of paint than could be done with a muller and stone.
Further along in the 18th century, colourmen and pigment producers used horse-powered mills to grind paint in large volumes to sell readymade. This process entailed hitching a horse to large geared wheel, which transferred power to a number of lantern pinions, each of which drove a pair of grind stones. The top-most runner stone had a hopper affixed to it that held the oil and pigment. In principle these colour mills worked just like gristmills, using the shearing force of the two grindstones to efficiently pulverize the pigment further and mix it thoroughly with the oil. Below you can see a detail from Joseph Emerton's trade card showing such a horse-powered colour mill in action.
We also see Rawlinson's colour mill hit the scene in the early 1800s, though he was prototyping his colour mill in the last decade of the 18th century. Rawlinson's colour mill replaced grinding stones with a large black granite cylinder and a corresponding piece of granite that was cut to a complimentary arc. The corresponding piece was suspended over the granite cylinder on an adjustable spring, so the user could change the fineness of the grind by bringing the cylinder and the mating piece closer together. In use, the mill worked by loading the cylinder with the raw ingredients for paint and then rotating the cylinder around with a crank until the paint was thoroughly ground. Then the user would hinge a sort of boot-scraper up and rotate the cylinder in the opposite direction, scraping the paint off the surface of the cylinder so it could fall down to a collecting dish below.
Vehicles
Now finally lets look at the relationship between paint and vehicles in the 18th century. First we will look at how paint was used and what colors were in vogue in the context of work vehicles - the product of wheelwrights in the 18th century.
Whether it was a wagon, cart, or wheel barrow, painting them was a universal practice. This practice sometimes takes guests by surprise. The wood is so beautiful! Why cover it up with paint? The answer is manifold. Firstly, the woods we typically use to build vehicles were not considered "pretty" woods by 18th century standards. It's true that today we love to see oak, ash, and elm finished in the clear, however, to the 18th century eye these woods were not exotic nor fashionable, they simply reminded them of firewood. So covering up these lowly woods with paint was a no-brainer to the wagonbuilders in the 1700s. The second and perhaps more important reason is that painting the wood protected it from rot and degradation. As explained above, the oil with which the paint was made was routinely fortified with lead as a drying agent. The lead functioned both as a drying agent and a biocide, killing the microbes that wanted to eat the wood and kill the cart. In addition, the linseed oil naturally polymerizes creating a kind of skin which sheds water more readily. Rather paradoxically, however, the cured paint is still permeable to moisture! The good news is that since the paint is permeable, whatever water finds its way in, can also find its way out. If instead the water was trapped by a water-impermeable skin, the wood would have a much higher likelihood of rotting. In this way linseed oil paint performs better than latex paint which produces an impermeable skin on the wood.
Above you see a watercolour by John Harris entitled Farmworkers and Cart which dates to 1797. There are two things worth noting here. One is the bright green color of the body. Remembering that this is a farm cart, its remarkable that such a strong and vibrant color would be used for a utilitarian vehicle. But, is it really? If we consider the color schemes for modern day tractors, strong primary colors are the go-tos. Bright green for instance is now synonymous with John Deere. So even as far back as the late 18th century, work vehicles were brightly colored and perhaps when the tradition was established that led to all the brightly colored tractors and farm vehicles of the 20th century.
In this vein, lets now look at the spectacular illustrations of James Arnold. Arnold was a skilled illustrator who was active in the early and mid 20th century. As the story goes, he was an avid cyclist and toured much of the English countryside by bicycle. During his outings, he'd come across old farm wagons. He quickly became enamored. He soon took it upon himself to painstakingly measure, record, and illustrate the old wagons he discovered, eventually publishing his illustrations in a book entitled The Farm Waggons of England and Wales in 1969. Below you will see a sampling of four of these illustrations. While it is true that Arnold is depicting vehicles that are mostly 19th century in origin, one can argue that wagonbuilding and painting practices were fairly conservative and did not change much over time. So what we see being practiced in terms of wagon color schemes in rural England in the 19th century, most likely reflects conventions held in the latter part of the 18th century as well.
Outside of Arnold's skill, what is remarkable about the above illustrations is the range of color schemes that Arnold observed on these farm vehicles. Despite being working vehicles—bound to carry hay, manure, and dirt—the wagonbuilders and farmers still felt compelled to paint them with strong contrasting color schemes. These vehicles were more than just useful, they were art objects as well.
Another characteristic in Arnold's wagons which is shared by the cart depicted in Harris' watercolour is a red undercarriage. What's going on here? Why do so many wagonbuilders and wheelwrights opt to paint the chassis red?
The answer is not (necessarily) that red was the best or most fashionable color. Instead, it had to do with what kind of paint would best protect the undercarriage from rot. The answer? Red lead. Red lead was in fact often used as a priming coat because of its high toxicity. And nowhere is that more important than the undercarriage. The chassis is the most critical part of the wagon or cart's construction, requiring very heavy timbers and careful fabrication. In turn, the undercarriage is also disadvantaged by being rarely dried out by direct sunlight and more often wet and muddy from use in the road or field. In other words, the undercarriage is highly rot-prone. The solution from the wagonbuilders perspective is a liberal application of red lead paint. So why not then cover it up with a more attractive color? Well, it's a wagon. Why bother?
Above is a picture of a Virginia Connestoga wagon we have in the collections at Colonial Williamsburg. This wagon was likely built in the early 19th century. Note the prussian blue body color paired with the red lead undercarriage. You even see red lead used for the interior of the wagon body, again to provide greater protection against the elements.
So, I would be remiss if I didn't include carriages in my survey on paint and vehicles. Unlike with wagons and carts, however, carriage painting was tuned to the latest fashion and thus changed more rapidly when compared with work vehicle color conventions. Paint schemes for carriages in the 18th century were loud, vibrant, and even garish by modern standards. The gentry had a broad palate for color and their vehicles reflected that fact. Below you will see a number of carriage illustrations from William Felton's Treatise on Carriages from 1794.
In summary we've seen how paint is made and how it was used on vehicles in the 18th century. As previously remarked, color was all the rage in the period. Whether it was a house, a ship, or a lowly wheelbarrow, the folks in the 1700s desired to both protect the wood from decay and give the objects some style and curb appeal. The range of pigments available to the painters of the 18th century was surprisingly vast, and so in turn was the taste for color.
Murphy Conn Griffin
Journeyman Wheelwright
Sources:
Felton, William. A Treatise on Carriages. The Astragal Press, 1794
Baty, Patrick.. The Anatomy of Color. Thames & Hudson, 2017.
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