Materials for permanent painting; a manual for manufacturers, art dealers, artists and collectors

Front matter

Materials for

City 1.! :• f ' • past Preside’'- •' - Past ChaimiHi

Director ot ' ' .iroth'

Preface

I,

History of Painting.

II,

Pigments used by the Ancients.

III,

Sinopia, the Search for the Mas-

IV,

ters’ secret.

Photo-Chemical Deterioration of

V,

Oil Paintings.

Cause of the Cracking of Paintings

VI,

and the Remedies.

Canvas, Wood and Metal as Foun-

VII,

dations.

Preparation of Canvas in Commer-

VIII,

cial Practice.

Renovation and Cleaning of Pic-

IX,

tures.

The School of Impressionism.

X,

Volatile Solvents.

XI,

Picture Varnishes.

XII,

Driers.

XIII,

Linseed Oil and Other Drying Oils.

XIV,

Classification of the Pigments and

XV,

their Description.

The Permanent Colors.

XVI,

Pigments Dangerous to Health.

XVII,

Pigments afifected by Coal Smoke,

XVIII,

etc.

Water in Tube Colors.

XIX,

Pigments which are Permanent,

XX,

etc.

Pigments which Dry Slowly.

XXI,

The failure of Sir J. Reynold’s

Paintings.

LIST OF ILLUSTRATIONS

Page

Gesso Tempera Painting on Wood Frontispiece

Photo-Micrograph of a Section of an Oil Painting Showing Cracks 40

The Engineering Features of a Painting at Rest. . 42

Photo-Micrograph of Cracks in a Painting, and Dirt and Dust Encysted in the Varnish 45

Painting on Mahogany Panel Showing Serious Cracks Produced by Varnishing the Picture Before the Imderlying Coat was Sufficiently Dry. . 48

Photo-Micrograph of Cracks Invisible to the Naked Eye Showing Encysted Matter and Fissures... 63

Photograph of an Oil Painting Showing Serious Cracking Throughout, Due to the Contraction of the Paint 80

High-power Photo-micrograph of Flake White which Contains too much Water in its Composition 185

IN the course of my acquaintance with artistic painters, I was astonished to find the enormous amount of ignorance that exists among them as to the composition of the materials which they use and the science of painting. Almost every painter of note will tell you what a great pity it is that the science of making colors is lost, and that the ancient painters and great masters were so successful primarily because their pigments and materials were far superior to those which we can obtain to-day. This statement is so diametrically opposed to the facts that I have been prompted to make a study of paint pigments in order to throw some light on this subject, and demonstrate to the painter that the colors of to-day are far superior to the colors used by the ancients, and show that the principal fault lies with the manufacturer, who makes fugitive colors, for the use of which there is no scientific nor commercial reason. Almost any large dealer in artists’ colors has upwards of 200 pigments on sale. In the first place, no palette could hold any such quantity, and in the second place, there are possibly only 10 or 15 sufficiently permanent pigments to warrant their use.

The correct, complete and most edifying book on this subject has never been written, nor is my efifort of much value, excepting perhaps from the standpoint of the chemist. Some day there will be born a man, who will be both a color chemist and a painter, and that man will write the ideal book on the subject. The popular impression is that all chemists must have a comprehensive knowledge of the chemistry of pigments, but this is not true, as there are very few chemists who know anything about the technology of paints, because it is a specialty which very few have worked up, and no matter how proficient a chemist may be, if he is not an artistic painter, he cannot advise how a sky should be painted, or what particular greens to use for foliage and shadows. The technique of the fine arts is a subject by itself, and while I may be supposed to have some knowledge on this subject, I frankly admit my inability to paint, but inasmuch as I feel very certain of one part of my subject, that is the physical and chemical properties of the pigments, I do not hesitate to recommend in plain language exactly what the painter shall do with reference to his colors, and the materials upon which he paints.

Furthermore, I was very much astonished to find that in the art schools of the various countries no attention whatever is paid to the chemistry of colors. A painter should be aware that certain pigments are affected by the fumes arising from vegetables in a dining room, and that these fumes form chemical compounds with certain pigments, and a painter should likewise know that the atmosphere of large cities is contaminated with acid gases which are absent in smaller places, and which did not exist before the age of the burning of coal as fuel.

I trust, therefore, that my work will be taken seriously, and that the poorer painter will recognize that he need not use expensive colors to produce permanent results. I am glad that I am not actuated by any commercial motive in writing this book, for, although I have been a color manufacturer for many years, I have never made, nor have I the intention of making tube colors for artists’ use, but I have made quantities of finely ground colors for many of my friends, who are painters, and have demonstrated to them that sometimes the ordinary paints ground in oil, such as are used by house decorators, are sufficiently good for many purposes, and in many instances produce the same results as the more expensive colors filled in tubes. I have tried to write as fully as I know and give as plainly as I could the description relating to the more expensive colors, condemning those which should be condemned, and recommending others as long as there is nothing superior to be had.

It may interest the reader to know why I take such a positive stand with reference to the fading, drying and other physical characteristics of colors, in view of the fact that the majority of investigators vacillate continually.

Pref ace

In 1886, while I was still a chemical student, I made my first investigation of tube colors, and from that day to this I have been interested in the subject of the manufacture of paints and pigments as a vocation, and have always been interested in the subject of the application of artistic pigments as an avocation. Drying tests can, of course, be conducted in a few weeks, but extensive tests take years, and although it is reasonable to determine the permanency of a color by exposure to the bright sunshine for three months, I have made experiments along these lines which have involved exposure for over five years.

When pigments are mixed with an aqueous medium containing a little gum, and the resulting picture is hermetically sealed, no decomposition takes place, because the majority of chemical reactions cease in the absence of moisture, but linseed oil or varnish medium will generate moisture and certain gases, producing a slow decomposition, so that it often takes years to make a determination of which a description can be written in a few minutes.

It is a great pleasure for me to acknowledge the assistance I received from Dr. George F. Kunz, who gave me a fairly complete collection of semi-precious minerals, all of which represented the pigments used by the ancients and with which I conducted many of my experiments.

Chapter I The History Of Painting

The decorative art of using colors is probably as old as man. We have the instinctive efifort of the barbarian, who bedecked his body with colored earths, and we have the frescoes and wall decorations and the painting of the columns in the temples of Luxor and Karnak, as evidence of the use of pigments for decorative purposes. There seems to be little doubt that from the earliest day of decorative painting down to the fourteenth century, the media used consisted of some albuminous or gelatinous compound mixed with water. The white of egg or the entire egg mixed with lime was evidently the principal medium used to fasten colors, although many other substances were used, such as the liquid obtained by boiling parchment and the skins of animals in water, which is practically the same thing as using glue.

In the method of painting with the white of egg which has always been known as tempera, the paint was generally applied to a ground of gesso, which is the Italian word for gypsum, or plaster of Paris, and the pigments which were used, and the methods of preparation of the wood foundations for painting were so perfect that absolutely no decomposition takes place in gesso tempera painting, for we have brilliant examples that are over 600 years old practically in their pristine condition. Pliny mentions the use of milk as a medium, and while it is doubtful whether we have any authentic samples of early paintings with milk, we have the custom still in vogue, for there are thousands of tons of kalsomine or water colors made at the present day in which the binding material is casein, which is the gluey substance that is contained in milk. In addition to these media the early monks used almost every conceivable substance of a sticky nature, such as wax, honey, wine boiled until it is slightly thickened (glucose or sugar), the juice of various plants, and from the eighth century on we begin to have evidence of the use of drying oils in the form of some nut oil (more than likely linseed oil mixed with a varnish), for in Italy before the days of oil, we have, according to Cennini, the mention of vernice, from which evidently our word “varnish” has been etymologically derived.

Oils were known to the ancients as an article of food and as a material for anointing the body, sufficient evidence for this being found in the Bible, and as many priests busied themselves with painting and used the materials at hand, there is no doubt that many of them used cooking oils such as olive, flax and nut oil in many of their works. Eastlake, in his most valuable book,* makes the statement that Aetius, a medical writer of the fifth and the beginning of the sixth century, mentions at great length, a drying oil in connection with works of art, and it was this early writer who described at full length what we probably recognize as “linseed oil,” and after mentioning this, he makes the statement, “walnut oil is prepared like that of almonds, either by pounding or pressing the nuts, or by throwing them into boiling water after they have been bruised. It has a use besides a medicinal use, being applied by gilders or encaustic painters, for it dries, and preserves gildings and encaustic paints for a long time.”

The popular statement that the brothers Hubert and Jan Van Eyck were the first to paint permanent pictures in oil, is only true in so far that both of these men evidently investigated all the work that had been previously done, as the Italian historian, Facius, speaks of Van Eyck as having consulted the previous authorities with much profit, t Facius, whose full name was Bartolommeo Facio, appears to have first published his work in 1456, but we have ample evidence as far back as Henry HI, in 1239, showing that oil painting was practiced in England as a trade. In view of the fact that the work by Sir Charles Eastlake is to be found in few libraries, and that his celebrated book is therefore not easily accessible, I quote from his in-

* Materials for a History of Oil Painting, t Eastlake’s Material for the History of Oil Painting, p. 25.

vestigations as follows: “In 1239 (23d of Henry III) oil is mentioned in connexion with painting. Similar notices appear in numerous account-rolls belonging to the reign of Edward I, viz., from 1274 to 1295; and in others dated 1307, the ist of Edward II.” Another series exists in the records of Ely Cathedral, the dates extending from 1325 to 1351. A great number of the same kind are preserved in accounts belonging to the reign of Edward III, and relating to the decoration of St. Stephen’s Chapel, from 1352 to 1358. Partial translations (unfortunately without the original text) of some of the last-mentioned records have been published in “Smith’s Antiquities of Westminster.”* The extracts made by that writer relate to glass-painting, architecture, and decorations generally. Of certain weekly accounts (belonging to the reign of Edward I), amounting originally to one hundred and forty-two in number, he states that he had found eleven only, t In the course of a recent investigation forty-four have been discovered. However interesting in other points of view, these numerous documents throw but little light on the practice of oil painting. The same materials constantly reappear, but there is no direct allusion to their use, except as regards the process of varnishing. Such passages as the following refer to the commonest operations of this kind: “To the same (Stephen Le

Joigneur) for varnishing two coffers, 8d.” ;* and else, “To Richard de Assheby for preparing with white, covering with ochre, and varnishing the King’s Chamber, according to contract. 32 shillings.” t A few specimens of the mandates and accounts above adverted to, beginning with those of the thirteenth century, will therefore suffice. The first in order of time is familiar to many, having been originally published by Walpole.

1239. “The King to his treasurer and chamberlains. Pay from our treasury to Odo the goldsmith and Edward his son one hundred and seventeen shillings and ten-pence for oil, varnish, and colours bought, and for pictures executed in the Queen’s Chamber at Westminster, from the octaves of the Holy Trinity (May 25th) in the 23rd year of our reign, to the feast of St. Barnabas (June nth) in the same year, namely, for fifteen days.” t

It is here necessary to remark, in anticipation of the inquiry respecting varnishes, that the word vermx or vernisium, in the earlier notices of painting, does not mean a fluid composition, but dry sandarac resin, which, when melted and boiled with oil, formed a

* "‘Eidem (Stephanno le Joignur) pro vernicione ii. coffro rum Viii. d/’

t **Richardo de Assheby pro bealbacions ocriacione et ver nacione camere Regis ad tascham xxxii. s.”

t “Rex thesauriario et camerariis suis salutem. Liberate de thesauro nostro Odoni aurifabro et Edwardo filio suo centum et septemdecem solidos et decern denarios pro oleo, vernici, et coloribus emptis, et picturis factis in camera reginae nostrae apud Westm. ab octavis Sanetae Trinitatis anno regni nostri xxiii. usque ad festum Sancti Barnabe apostoli, eodem anno, scilicet per xv, dies.** varnish, in the modern sense of the term. The proofs of this will be given hereafter. It may be sufficient here to observe, that, in the English accounts, the quantity of varnish is always noted by weight, and that of oil by measure. The above passage should be translated “for oil, sandarac resin, and colours.” It will be seen, that the order relates to the work of fifteen days only ; but it does not follow that the oil varnish was used upon pictures, or operations in painting, then executed. In the portion of time specified some works may have been varnished and others prepared for it. The date of this mandate is a year before the birth of Cimabue.

In 1259, Master William, the painter, with his assistants, received forty-three shillings and ten-pence for painting a Jesse (no doubt the usual genealogical tree of Christ) on the mantel-piece of the King’s Chamber (The Painted Chamber), and “for renovating and washing the paintings on the walls of the said chamber.” *

This supposes that these celebrated works, consisting chiefly of subjects from the Old Testament and from the Apocrypha, were varnished. Size paintings, without such a protection, would hardly have been proof against this “ablution.” The tempera, composed chiefly of yolk of egg, is firmer than size, and becomes very solid in time ; but the colored remains of the

Painted Chamber (the varnish probably having become decomposed from damp during the lapse of ages) easily yielded to the sponge when they were examined in 1819. *

In the period from 1274 to 1277 (3rd to 5th of Edward I), an account, apparently relating to the Painted Chamber, contains the following items ; “To Reymund, for seventeen fb. of white lead, ii. s. x. d. To the same, for sixteen gallons (?) of oil, xvi. s. To the same, for twenty-four lb. of varnish, xii. s. To Hugo le Vespunt, for eighteen gallons of oil, xxxi. s.,'' etc. t Again; “To Reymund, for a hundred (Leaves) of gold, hi. s. To the same, for twenty-two lb. of varnish, xi. s. i. d.” t Elsewhere: “To Robert King, for one cartload of cliarcoal for drying the painting in the King’s Chamber, iii. s. viii. d.“ §

The last entry appears to relate to the drying of surfaces painted in oil, but the precaution may also have been necessary before varnishing tempera. The application of heat, even before painting in oil, according to the directions of Eraclius, will here be remembered : “Ad solem vel ad ignem siccare permittes.’’ It can hardly escape observation, that the practice of oil painting taught by Eraclius agrees in many details

* See Gage Rokewode’s Account of the Painted Chamber, 1842, p. 15. t “Reymundo pro xviii. ii. albi plumbi ii. s. x. d. Eidem pro xvi. gal. olei xvi. s. Eidem i>ro xxiiii. li. verniz xll. s. Hugoni le Vespunt pro xviii. gal. olei xxi. s.”

t “Reymundo pro C. auri iii. s. Eidem pro xxii. li. verniz xi. s. i. d.” § “Roberto King pro i. carecta carbonis ad picturam in Camera Regis desiccandam iii. s. viii. d.”

[IS]

with that exemplified in the English records ; and the circumstance may warrant a supposition that he composed his treatise in this country. 1289 (17th of Edward I). The following materials are enumerated in an account relating to repairs in the Painted Chamber: “white lead, varnish, green, oil, red lead, tin-foil, size, gold leaf, silver leaf, red ochre, vermilion, indigo, azure, earthen vessels, cloth, etc.” *

In 1292, oil and varnish are twice mentioned in a similar account, t In 1307, in consequence of a fire (which occurred in 1298), repairs were again undertaken, and similar materials were used.

The records of Ely are more conclusive as to the mixture of oil with the colors ; and, as the materials are nearly the same as in the above extracts, it may be inferred that oil painting of some kind was employed at Westminster. Of this, indeed, there are other proofs.

1325. Among the items of an account, three flagons and a half of oil are mentioned “for painting

* “In albo plumbo, vernicio, viridi, oleo, plumbo rubeo, stangno albo, cole (Fr. colle), auro, argento, sinople, vermilone, ynde, asura, ollis, panno et alHs minutis emptis ad viridandam novam Camereram de petra et ad emendaciones picture mangne Camere Regis sicut patet per particulas. Summa xii. li. vl. s. vi. d. ob.’’ This extract is given in the work last quoted, but with some inaccuracies; for example, ranno for panno, and in the heading, verniorum for verinorum. There is no punctuation in the original account-rolls, but vernicio viridi should not have been connected. It would be unjust to point out these trifling oversights in an important and interesting work, without, at the same time, paying a tribute of respect to the memory of one who so often distinguished himself as an accurate and intelligent investigator.

t Item in iii. quarteronis olei empti. Summa ix. d. In I. lb. vernicio (sic) empt. Summa iiii. d. In ocra, piastre, filo et pelli emptis,” etc.

the figures upon the columns.”* The term “ymagines,” in these and other English records of the time, is used indiscriminately for painted figures and for statues. In the treatise of St. Audemar the latter are distinguished as “ymagines rotunde.” There can be little doubt that, in the above passage, painted figures were meant ; and, in any case, oil colors were used.

In 1336, in a similar account, oil appears in abundance, forty-eight flagons altogether ; and this may explain its absence in other entries, where colors and other materials are mentioned without oil. It should also be observed that, if, in mutilated documents, “varnish” appears alone, it may always be inferred that the oil (without which the vernix, or sandarac, was of no use) was originally included in the list of materials. In the last mentioned account columns were to be painted, t

In 1339 and 1341 oil again appears; in the account of the former date “for tempering the colours.” t

In 1351 oil is mentioned “for making the painting in the chapel.” § In all these documents, when varnish

* “In iii. lagenis et dimid. olei pro ymaginibus super columnas de* pingend. iii. s. vi. d.”

XX

t “Item in vii. iv. albi plumbi emp. de eodem xii. s. prec. i. d. In xiii. lagenis olei wmpt. de Thoma d’Elm x. s. iii. d. ob. prec. lagen. X. d. oU In vi. lagenis olei empt. de Thoma de Chayk iv. s. xi. d. prec. lagen. x. d. In xxviii. lagenis et dimid. olei empt. de Nich. de Wickam xxvi. s. i. d. ob. prec. lagen. xi. d. In dimid. lagen. olei empt. v/d. In vas terren, pro oleo imponendo iv. d. quad. In i. longa corda empt. pro le chapital deaurand. et column, depingend. viii. d.,’^ etc.

t “In xxxi. lagenis et dimid. olei empt. de quodam nomine de Wickham pro coloribus temperandis xxl. s. prec. lagen. viii. d.,“ etc,

§ “In oleo empt. pro pictura facienda in capella x. s.,“ etc. The above extracts relating to Ely Cathedral will be found in the Archaeologia, vol. ix.

is included in the items, the quantity, as usual, is noted in weight.

The last accounts in the general list before given (1352-1358) relate to St. Stephen’s Chapel. They are very numerous ; but, as already observed, they afford no additional light respecting the particular applications of oil painting. In other respects they are of great interest ; and, like those of the time of Edward I, indicate a practice in art corresponding in almost every particular with that described by Cennini.

The large supplies of oil which appear in the Westminster and Ely records, indicate the coarseness of the operations for which oil was required. The quantity supplied to Giorgio d’ Aquila, at Pinarolo, has excited the surprise of Italian antiquaries ; * but it now appears that contemporary examples, quite as remarkable, are to be found in English documents. Such notices as the following (not the only entries of the kind) at least remove all doubt as to the nature of the oil sometimes used, and the general purposes for which it was provided.

The extracts relate to St. Stephen’s Chapel. Sept. 19, 1352, (25th of Edward III) : “For nineteen flagons of painters’ oil, bought for the painting of the chapel, at 3s. qd. the flagon, 43s. qd.” t March 19, 1353:

Eression, “non erat sufficiens in pingendo,” that the oil may have een used for lamps.

t “Die Lune xix. Septembris. In xix. lagenis olei pictorum emptis pro pictura capelle precium lagene iii. s. iiii. d. xliii. s. iiii. d.“

“To Thomas Drayton, for eight flagons of painters’ oil, bought for the painting of the chapel, at 2s. 6d. the flagon, 20s.”* May 13, in the same year: “To John de Hennay, for seventy flagons and a half of painters’ oil, bought for the painting of the same chapel, at 2od. the flagon, 117s. 6d.” t Contracting with this lavish use of oil, we find such entries as the following: “To Gilbert Pokerig, for two flagons of size, bought for the painting of the said chapel, 2d. To the same, for two earthen vessels for heating the size, three halfpence.” t

Eggs, which afforded the vehicle for the finer work in tempera, are not mentioned: this may, however, be accounted for either by the incompleteness of the records of this period, or by the nature of the work, as. the item occurs in earlier documents, hereafter to be noticed, belonging to the reign of Edward I (1274). It will be observed that tlie price of the oil used in St. Stephen’s Chapel varies, and that sometimes it is more than three times the price of that employed at Ely about the same time. The expression “painters Oil,” applied to the former, may explain this. It had been probably purified and deprived of its mucilage by exposure to the sun, in the mode then generally

* “Die Lune xix. die Marcii. Thome Drayton pro viii. lagenis olei pictorum emptis pro pictura capelle precium lagene ii. s. vi. d. xx. s.”

t “Die Lune xiii. die Maii. jTohanni de Henr.aij pro ixx. lagenis et di. olei pictorum emptis pro pictura ejusdem capelle precium lagene XX. d. cxvii. s. vi. d.”

t “Die Lune xix. die Marcii (1353). Gilberto Pokerig pro ii. lagenis de cole emptis pro pictura dicte capelle ii. d. Eidem pro ii. ollis terreis emptis pro cole calefaciendo i. d. ob.”

practiced for the preparation of linseed oil which was to serve for better kinds of painting (on surfaces where it was desirable to produce a gloss), and for the composition of varnishes. This appears the more likely, as the oil was sometimes purchased of the (then) principal painter, Hugh of St. Albans. *

Cennino Cennini gives the most exact formulas for the preparation of drying oil and varnishes, including prescribed methods for the grinding of colors in oil for painting in oil on iron and on stone, and one of the most noteworthy facts that we have in conjunction with this remarkable Italian investigator is, the fact, that the description of the varnish kettles for the melting of the gum, and the implements used for stirring are almost identical in shape with those that are used in the present day, and in his description of the preparation of drying oil which we now popularly term “gold size,” is a slow-drying linseed oil that remains “tacky” for several days, and dries without shrivelling. It is also noteworthy of mention that our methods for making an oil size do not differ to-day from the formulas prescribed by Cennini.

The early Italians were better book-binders than they were painters, and as nearly all of their subjects were of a religious nature, the madonnas with the gold-

* “Die Lune xxv. die Julii (1352) Eidem (Magistro Hugoni de Sancto Albano) pro xiii. lagenis olei pictorum emptis pro pictura diste capelle precium lagene iii. s. iiii. d. xliii. s. iiii. d.” The same quantity, at the same comparatively high price, is entered on the 19th of September following. This extract has been already given.

en background, the saints with the golden halos, were all so wonderfully prepared, that to this day we have excellent examples of this art, which is really a mixture of book-binding and painting.

About the year 1400, the practice of oil painting had become thoroughly established, due undoubtedly, to the research and investigation of the Van Eycks. The examples of their oil painting which are in existence to this day are in a condition that is absolutely remarkable. Even a superficial examination of one of the paintings of Hubert Van Eyck in the National Art Gallery in London, shows a brilliancy and freshness that pays an inexpressible tribute to the wonderful care exercised by this master and his brother.

Chapter II The Pigments Used By The Ancients

The permanence of the old paintings is entirely due to the fact that the painters had very few pigments to work with, and practically all of them were native earths which were in many instances exceedingly brilliant. The lapis lazuli which is the same thing as our ultramarine blue of to-day occurs in nature, and varies in shade from a greenish sky blue to a dark ultramarine. The selection of various shades of this most permanent pigment gave to all the painters who used it a blue which has not been surpassed.

For the yellow pigments there were ample yellow earths in the form of ochre and sienna, which while not very brilliant were sufficiently bright for all purposes.

The white effect about the gesso paintings was produced by whiting and gypsum, and as white lead was known 400 B. C., either as an artificial product or as a mineral known as cerusite which is a native carbonate of lead, the use of this pigment was well known and largely practiced, although its defects were noted by nearly every one of the early writers.

As far as green is concerned, there were several varieties of minerals that furnished green, principally malachite, which is a form of carbonate of copper, and no doubt when properly glazed was found to be amply permanent, although sulphur gases aflfected it.

In addition to these pigments they had Grecian green or Graecum which the French later on, called verte de grece, from which the term verdigris is derived. Whether this was metallic copper subjected to vinegar as we now know it, or whether it was the turquoise mineral or clayey earth stained with phosphate of copper, as may have been the case, it is difficult to say, for the verdigris that we know in modern art is transparent, and has the qualities of a lake or stain, and not the qualities of a paint.

Concerning the reds which the ancients used, we know that they were familiar with all the red oxides of iron, and the Italians used not only calcined sienna which is a brownish red and now recognized as burnt sienna, but they also calcined ochre, which made a yellower red. The bright red or vermilion used from the thirteenth century on under the name of sinopia, deserves a chapter for itself, and will be described later on.