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1.5 Mediums and fixatives

All of the catalogues of Winsor & Newton, Reeves and Rowney which have been included in this research contain three mediums which were sold as an aid to watercolour painters: ‘prepared gum water’, ‘colourless liquid ox gall’ and ‘water colour megilp’.

Prepared Gum Water was sold in small, middle or large size bottles costing between 6d and 1s. 6d. and came with no description in the catalogues, so clearly it was expected that everyone knew how to use it. Still available today, it is made from gum arabic (also known as Senegal gum), which exudes naturally from certain species of Acacia tree and is often sold in colourless rounded lumps.¹⁶⁴ Gum arabic has from the start been one of the ingredients used in the manufacture of moist watercolours, acting as a binder to help the dry pigment adhere to the page.¹⁶⁵ While its main use was said to have been by figure and miniature painters, many artists, including John Frederick Lewis, Dante Gabriel Rossetti and Edward Burne-Jones used gum to strengthen their

shadows or occasionally as an overall varnish.¹⁶⁶ Burne-Jones’s watercolours were described by his studio assistant, Thomas Rooke, as ‘a tempera of gum and water.’¹⁶⁷ Because his heavily-gummed opaque watercolours were often mistaken for oils, Burne-Jones took the precaution of writing notes on the back of the works explaining they were in watercolour. Love Among the Ruins was unfortunately ruined as a result of such a misunderstanding.¹⁶⁸ The Redgraves suggest a reason for the growing popularity of gum: ‘The use of gummy solutions to strengthen and give force to the darks of the picture, has certainly been promoted by the law of close framing,’ a regulation introduced by the Society of Painters in Water Colours.¹⁶⁹ Other artists used gum arabic as a protective coating over unstable pigments, such as Pure Scarlet, preserving them from contact with air or metallic substances, which would fade or discolour them.¹⁷⁰

Colourless liquid ox gall also came in bottles, priced at 1s. 6d. from Winsor & Newton and Rowney and 1s. from Reeves. The Rowney catalogue carries the following description: ‘This limpid extract of Gall possesses all the strength and properties of the Gall as it is usually sold in the paste state, but is deprived of its unpleasant qualities.’¹⁷¹ The ‘Prepared Ox Gall’ was sold separately in covered pots.

The use of ox gall in watercolour painting was explained by George Barnard in 1871.

‘Should the colours or washes not be evenly laid on, or attach themselves to the paper, a little gall may be dissolved in the water: a small piece about the size of a pea, dropped in the glass of water, or a few drops of the solution, will be sufficient.’¹⁷² In modern terminology, ox gall ‘reduces the surface tension of the liquid (water, when mixed with pigment) but is also an efficient wetting agent for the surfaces,’ as some grounds repel water.¹⁷³

Pots of ox gall are listed amongst Burne-Jones’s purchases from Roberson in 1865 and 1872 (see Appendix IX) and the medium has been identified in works such as Sidonia von Bork of 1860 (Figure 145). Field writes that ‘animal gall is necessary only to attach the colours to the ground when it rejects them, or they work greasy, as is often the case on ivory and very smooth vellum or polished substances, or over certain pigments.’¹⁷⁴ As many of Burne-Jones’s early watercolours were on vellum, this may explain his purchase of ox gall at this time.

Water Colour Megilp

Watercolour Megilp was listed in Winsor & Newton’s 1849 catalogue as a new product

invented and prepared by Winsor and Newton, for the use of Water Colour Painters. A most desirable medium, imparting additional depth, brilliancy, and transparency in Water Colour Painting, improving the working of the colours, and preventing them running into one another.¹⁷⁵

Named after its oil counterpart, the watercolour version was made from gum tragacanth.¹⁷⁶ This gelatinous medium acted as a thickening agent, allowing colours to be ‘applied pulpily, after the manner of Oil Painting’.¹⁷⁷

Reeves and Rowney also advertised watercolour megilp in their catalogues at this time, with Reeves in 1862 offering a variation called ‘Reeves and Sons Wax Water Megilp’

(‘Magulph’ in the 1879 price list). This medium was said to give ‘a brilliancy, transparency, and depth to the colours never before attained, with a certainty of their never cracking or peeling off.’¹⁷⁸

In Chromatography, Field suggests the use of tragacanth ‘when colours are required to lie flat, or not bear out with gloss, and also when a gelatinous texture of the vehicle is of use to preserve the touch of the pencil and prevent the flowing of some colours.’

Isinglass and starch, he says, are also suitable for the same purpose.¹⁷⁹ John Chase writes that tragacanth ‘fixes the underneath colour so that other tints may be washed over with freedom.’¹⁸⁰ Watercolour manuals dating from 1850, 1857 and 1861 all contain descriptions of the use of gum tragacanth and more will be said in the next chapter about this. ¹⁸¹

Other products

Rouget’s Fixative, known to Palmer and ordered in quantity from Roberson by Burne-Jones at regular intervals between 1869 and 1879,¹⁸² may have been a relatively new product in England at that time, because it was only being promoted in the press in 1870 as a way of preserving both charcoal and pencil drawings and watercolours (Figure 176).¹⁸³ By 1861 Carl Haag also devised a fixative composed of White Wax and spirits of lavender, designed to preserve watercolour paintings from damp and to give the colours used ‘all the brilliancy of oil-painting’.¹⁸⁴

Other innovative nineteenth-century watercolour vehicles were reported by Field, including two which won their creators gold medals from the Society of Arts: Mr.

Robertson’s ‘varnish’ made from isinglass (fish glue) and alcohol, and Mr J Hammond Jones’s solution of borax in water and gum tragacanth, which ‘dried sufficiently firm to allow tints to be repeatedly laid one over another without moving or washing up.’¹⁸⁵ It is clear that two issues were driving such innovations at this time – the desire for watercolour painting to take on the powerful appearance of oil-painting, and the need to render watercolours permanent and durable.