Blue explored in NGV exhibition Alchemy of a Colour

The National Gallery of Victoria’s fascinating exhibition on the colour blue traverses continents and centuries.

An 18th-century painting by India’s Bakhta. National Gallery of Victoria, Melbourne.

Isaac Newton, the father of modern optics, knew very well that the phenomenon of colour corresponds objectively only to differences in what we would now call the wavelengths of light reflected from things in the world. Our perceptual system codes these wavelengths into what we experience as colour to help us make more subtle visual discriminations, but what actually reaches our eyes is simply different quantities of energy.

Colour is perhaps the most easily intelligible example of the gap between the way that our senses perceive the world and the intrinsic ­nature of reality. And yet there are few sensory experiences, apart from smell, that have a more immediate effect on our moods and feelings, even before we consider the powerful cultural associations of colours.

But there are still more surprising aspects to our experience of colour. For the past century and a half, scholars have been pondering the relation between language — the range of words available to name colours — and the hues that we actually see, or perhaps we should more accurately say, consciously distinguish.

In 1858 William Gladstone, later Liberal prime minister of Britain, published an extensive study of Homer and the Homeric world, pointing out among other things that Homer’s vocabulary of colours seemed strangely limited. Black and white appear frequently, red is ­relatively common, but there seemed to be no word for yellow nor, most strikingly, for the colour blue.

Whether this is absolutely correct depends on how one is to understand the words kuaneos, from which we derive the word cyan, and which later meant dark blue, though it probably signified black or simply very dark to Homer, and glaukos, usually thought of as blue-grey, like the eyes of the goddess Athena, though perhaps originally only bright. But the fact remains that Homer does not describe either the sea or, even more surprisingly, the sky as blue even in the course of a story as exposed to both as the Odyssey.

Gladstone suspected — with brilliant insight as it turned out — that Homer’s colour terminology was essentially tonal. He inspired an equally brilliant contemporary in Lazarus Geiger, who studied other ancient texts, including the Vedic hymns, the Hebrew Bible and ancient Chinese, and similarly found no trace of blue. But Geiger went further and inferred the order in which colour names appear in the history of languages.

In the age of Darwin, Geiger was tempted to postulate that our ­capacity for colour vision had evolved physically since ancient times. Hugo Magnus developed this suggestion into a theory of the evolution of the eye that held sway until the early 20th century, when it gradually became clear that the physiology of perception had not changed within recorded history and that the explanation for the apparently slow develop­ment of colour terminology and perhaps colour perception was more likely to be found in culture.

The extraordinary intellectual adventure and often impassioned debates that began with Gladstone’s observation were related a few years ago in a fascinating book by Guy Deutscher, Through the Language Glass (2010), which sets the question of language and colour perception at the heart of broader debates about language and culture, and ultimately about the extent to which the structures of language are determined by nature or by culture.

Geiger’s theory about the order in which colour names appear in languages was essentially confirmed by Brent Berlin and Paul Kay in Basic Colour Terms (1969), although they were probably unaware of his work. All languages have words for black and white — proving the primacy of tonal value — and the first proper colour to be named is always red; the second is either yellow or green and the third is the other of yellow and green. This sequence may in fact shed light on the Homeric word chloros, which seems to mean yellow in some contexts and green in others. Only after all these colours have been identified is blue finally given a name.

The late adoption of blue, and its perhaps residually marginal status, may be reflected in the natural history writings of Pliny. Speaking of the great ancient painters of Greece 500 years before his own time, he observes that they restricted themselves to four colours, which turn out to be the universally earliest ones: black, white, red and yellow.

This passage in an author who was widely read in the Renaissance naturally caught the eye of contemporary artists and theorists, and although scholars differ in their estimation of its impact, it is hard not to be struck by the relative and sometimes complete absence of blue in the late work of Titian, paradoxically reputed to be the greatest colourist of all.

Deutscher suggests, following Gladstone, that we name a colour only when we are capable of making a pigment to produce that hue, and that once we have given it a name we are much more likely to perceive that hue in the world. The theory has an appealing logic, reminiscent of Benedetto Croce’s principle that we know what we make.

One explanation for the universal primacy of red from this point of view is that red pigments are the most universally accessible in the form of natural ochres and as such are used by tribal peoples all over the world. But the motivation for wanting to make red in the first place is undoubtedly its association with blood and life.

Blue, unlike red, is neither easy to produce as a pigment, nor common as a colour in nature, nor associated with anything vital and visceral like blood. There are, for example, many flowers and fruits that are red and very few that are blue.

The most notable exception — though seemingly a very big one — is the blue sky, which should have been even more inescapable to early people living almost entirely outdoors. But Deutscher cites an experiment he did with his infant daughter. He taught her the names of all the colours, including blue, and showed her examples of them; all except the sky. When at length he asked her what colour the sky was, she was stumped at first, and finally replied that it was white. Only after a couple of months of repeated questions did she finally conclude that it was blue.

Alone, apparently, of ancient peoples, the Egyptians had a word for blue, and as it happens they were also the only ones who had developed a blue pigment, what is known as Egyptian blue or blue frit — a glass-like compound of silica and copper that is ground into pigment. This pigment was most probably originally meant to emulate the blue of the precious lapis lazuli stone, which comes from Afghanistan and is found in early times in the art of Mesopotamia.

Interestingly, though, it does not seem to have been ground into pigment until the 6th century AD. In the Renaissance, ultramarine, as it was called, became the most precious of pigments, more costly than gold, and used for special subjects such as the robe of the Virgin Mary. At last at the beginning of the 18th century, a synthetic version, Prussian blue, was developed in Germany and the effect of this and subsequent synthetic blues on the history of art is the subject of an exhibition at the Norton Simon Museum in Pasadena until March.

The National Gallery of Victoria, meanwhile, has its own exhibition devoted to the colour blue, concentrating mainly on two pigments: cobalt, which is a mineral, and indigo, derived from plant sources. It is an intriguing story that is revealed, and one that joins cultures and peoples across long trade routes and centuries of mutual influence and exchange.

We may be surprised at first sight to learn that the Chinese imported their cobalt from Persia, which has the best mineral deposits, but even more so to realise that they began to manufacture blue and white wares with this cobalt for re-export to Persia in the 12th century. But Persia is very close to the source of lapis, and to the cultures where the blue stone was first highly prized. So it seems that it was from the Persians that the Chinese gradually, over the following two centuries, learnt to love blue.

Another 200 years later, when the Europeans opened maritime trade to the east in the 16th century, the West too fell in love with Chinese blue and white wares; it was a passion that never abated, and in the Aesthetic period Oscar Wilde spoke of “living up to our blue and white china”, by now a benchmark of elegance.

With such demand for the valuable imports, local manufacturers imitated the Chinese designs, especially in The Netherlands with delftware that often look surprisingly oriental until closer inspection reveals the evidence of a European rather than Chinese hand or, even more obviously, baroque motifs. There are some good examples of Chinese and Delft ceramics in the exhibition, and a couple of fine Indian miniatures show blue and white wares in princely settings, most likely not Chinese but Dutch products exported from Europe. Just to keep viewers on their toes, one of these Indian paintings also includes a door beautifully painted in rich ultramarine.

The other blue represented in the exhibition is indigo, a dye produced from a couple of different plants: in the West it was derived from woad, Isatis tinctoria, and in India from Indigo­fera tinctoria, which produced a more powerful dye and was extensively imported into Europe once the maritime trade routes had been opened up, in spite of various laws attempting to protect the traditional local industry.

In both cases the production of the dye was a complex process that often involved trade ­secrets, and the dyeing of the cloth was also a complicated process. The dye was not, as we might imagine, a deep blue, and cloth taken out of the vat did not at first appear blue at all: it was the chemical reaction of oxidisation, as the cloth dried, that produced the blue colour, but repeated treatments were required to produce a deep hue. The colour could not be painted or printed on to fabric, so patterns were made, as we see in numerous examples, by various forms of resist dyeing.

There are many textiles from different parts of Europe and Asia that, like most textiles, are more interesting to look at than to describe minutely. And here again there are a few images, which add another level of complexity: the two Japanese ukiyo-e prints that are included primarily to illustrate the traditional indigo-dyed garment of a wayfarer are in fact printed using the imported Prussian blue pigment, a ­piquant example of the exchange of technologies but above all testimony again to the deep appeal of a colour that apparently took so long to be discovered.

Blue: Alchemy of a Colour

National Gallery of Victoria, Melbourne, to March