SECT. I. Of colours in general.
COLOURS may be either PIGMENTS
or fluids. By pigments, is meant all fuch ielid bodies as require to be mixed with feme fluid, as a vehicle, before they be ufed as paints, (except in the cafe of crayons, where they are Ufed dry.) Thefe triage the far greateft part of die whole » the fluid colours being only a fiftall number employed along with water Co-1
lours j and afphaltum, which is femerimes em-ployed ifi oil painting.
Colours are diftinguilhed into feveral kinds, according to the vehicles in which they are Worked j as oil coiours, water colours, enamel colours, &c. As die feme forts of pigments, however, are, in many inftances, employed in more dian one kind of painting, as Vermilion and lake in feveral, and ultramarine in all. I
not diflribufe them into clafles, in that View, till I come to fpeftk of their particular application > but treat at preferit of them pro-*
mifcuoufly in teaching their general nature and > preparation; dividing them according to their affinity in colour only; fince this method of arrangement will not only render each article more eafy to be found j but, at the lame time, exhibit to the artift together the whole flock of every kind from whence he mull take what he wants on each occafion: by which, he will be the more enabled, to chufe what may bell fuit his particular purpofe. For the fame reafon, allb, this method is certainly more expedient than the dilpofing them in clafles, according to their natural relation to each other, as earths, minerals, vegetables, &c-, which would lead to the like kind of confufion and repetition.
The principal' ‘qualities in colours, conli- dered with regard to their perfection or foulti- nels, are two; purity of colour, and durable- nefs: purity of colour is, by the painters, called BRIGHTNESS j and the defeat of it FOULNESS, or fometimes the BREAKING THE COLOUR: durablenefs is called STANDING j and the negation or want of it FLTING or JFLYING OFFj which terms, forconcifenefs, I fhall ufe in fpeaking of thefe qualities.
Brightnefs and Jlanaing well are the only properties, which are neceflary to the perfection of every kind of colours; and they equally relate to all j but there are others, which are eflen- tial to many forts, with regard only to partial* lar purpofes and ufes: fuch of them, however, as do not foil within the general confideration of the nature of colours, will be treated of in thofe parts of the work where the particular ufes of colours come in queftion.
The moil confiderable of the more general properties of colours after pqjity and durable- nefs, or brigbtnefs, andJlanding well, are tran- fparency and opacity j for according to their condition, with refpett to diefe qualities, they are fitted to anfwer very different kinds of pur- pofes. Colours which become tranfparent in oil, fuch as lake, Pruffian blue, and brown / pink, are frequently ufed without the admixture of white, or any other opake pigment -, by which means, the teint of the ground on which they are laid retains in fi)me degree its forcé j and the real colour, produced in the f painting, is the combined effect of both. This is called GLAZING, and the pigments indued with foch property of becoming tran- iparent in oil, are called glazing colours. The lame holds good alfo of fuch colours as are tranfparent in water; only when they are there ufed in this manner, they are not called glazing but WAS HING colours. When colours have no degree of fuch tranfparency in the vehicle in which they are ufed, as vermilion, King’s yellow,- and lèverai others, they are faid TO HAVE A BODT, and TO COVER. The property of glazing or wajhing is of fo much importance, both in oil and water, that no other method can equally well produce the fame effeét in many cafes, either with regard to the force, beauty, or foftnefs of the colouring: and it is therefore very elfential to the he perfection of ieveral kinds of pigments, that they (hould poflefs this property in a copir plcte degree; but, in other inftances, the pfing (colours with a Arcing body is not lefs neceflary, efpecially fojr thf grounding or tyttig in, t\s it is called, pf many objects to be parted- Thepe is another material quality ip colours» that relates only to their ufe in oil, which is the rfryirig well and (as it is called) notjattening. By FATTENING is meant, a coagulation pf the oil, that frequently happens on its commixture with fevpral kinds of pigments, by die effoCi they have upon it; from whence, after fqjne time keeping, it is rendered of fo vifcid or glutinous a confidence, as to bp wholly incapable of he" ing worked with either brufli or pencil, 'f’his quality, when found ip them, deftrqys almoft wholly the value of fuch pigments for the purpoifes of the calqurmen ; who fell a great part pf them ground with Q‘l> and tied up in pieces of bladder, where they are kept hU there is a demand for diem; which frequently does not happen foon; and, therefore, gives time for their {polling in confequence of this quality But to printers, who mil? the cor lours for themfelyes, on their pallets, with the oil, this property is not an equal inconvenience, when in a lefler degree; only, in general, it mufr be obferved, that colours, in proportion to their tendency to fatten, are flow in drying; and when the oil once contracts this flate, it will be a very long time before it will Income duly hard and fom in the paintings.
There are two. other qualities of colour in general that relate only to-their teint hue, but which render them neverthelefs fit or impro-
per, in a very material degree* foe different pur-poses. They are distinguished by the names of WARMTH and COOL NE SS: terms which indeed are. ufed very frequently by painters $ but, for the moll part, very indefinitely, and without any precift or clear meaning» What is meant, when properly ufed, by warmth, is that fiery effect which a final! addition of yel-low gives, Co. a true red, and that glowing ap-pearance whiefy red imparts to either yellcw or blue. By warmth, therefore, in red, is to be understood a fmall inclination towards orange; by the fame term, applied to. yellow, a like tendency by the admixture* of red.} and, by the Same, again in. the cafe of blue, muff blc
understood its Slightly verging en the purple.'
By coolnefsy is to be understood, the oppo-site to warmth} but this.termi$ lel(dom ufed, except in Speaking of yellow and blue } and there it means, either the negation of that which caufes warmth, ora tendeaeyto green, in either colour, by a Slight admibetur^of the other.
The Senfe of the word’ warmth, when ap-plied to colouring or the combined appearance of various teints, muff not be confounded with that, which it baa. when Speaking of par-ticular colours} for there it relates to the pro-ducing a Strong effe<3t by the disposition or contraft of the colours, or the groffnefs of the teints, and not the quaBties, peculiar to, or in-hcvsnt in the colours themfelves.
The colpurs ufed in all the fcveral kinds of painting, except fome peculiar toename^ ate, as follows.
RED.
EWE.
CLASS I. ^Vermilion.
Native cinnabar.
Red lead.
Scarlet oker.
Common Indian red. Spaniih brown.
Terra de Henna burnt.
Scarlet or tending >to the prange.
Carptine.
Lake.
Rofe pink* Red oker. Venetian red
1
Crimfin or tending
to the purple.
CLASS II. rUltr amarine.
Ultramarine allies.
Pruffian blue*
Verditer.
< Cendre mue or funders blue* Indico.
Smalt*
Bice.
* w Litmus or lacmus.
i
f
TELLOW. <
CLASS III.
“King’s yellow.
Naples yellow*
Yellow oker*
Dutch pink.
Englifh pink*
Light pink»
Gamboge.
Malhcot.
Common orpiment*
Gail done.
Terra de Henna unbumt* Turpith mineral.
Yellow berry .walh» Turmeric walh.
Tindture of fafiron*
C^A|S
ITSED IN PAINTING, 9
GREEN.
CLASS JV.
i
Verdigrife.
Diftilled verdigrife, or duyfbds of verdigris
Pruffian green.
Terra verte.
Sap green.
CLASS V. GRANGE. I Orange lake.
PURPLE.
\
CLASS VI.
True Indian red.
Archal.
Logwood waflu
fiROJFN.
CLASS VII.
“Brown pink.
Bjftre.
Brown oker.
< Umhre.
Cologn earth.
Afphaltum.
»Spanifh juice or extraft of liquorice.
WHITE.
CLASS VIII.
* White flake.
White lead.
^ Calcined hartlhorn. i Pearl white.
Troy white. „Egg-fhell white.
SLACK.
CLASS IX. Lamp black. Ivory black. Blue black. Indian ink.
Thefe are all the colours at prefent in ufe, in this country, in any kind of painting, except iiich as are peculiar to enamel; in which kind pf painting, as but few of thefe are capable of combining with glafs, and enduring the necef- fary heat without changing the« nature, or being deftroyed, others are employed more fuitable to vitrification: for which reafon, as the compofitions for forming the enamel colours are very various, and bear no particular names, and the management of them has.very little relation to other kinds of painting, I (hall omit fpeaking of them till I come, to treat particularly of enamel painting«
Of the above enumerated colours, but few are in univerfal ufe; möft painters having only a felett fet out of them, and being, in general, unduly prejudiced againfe thofe they rejedt: and fome of the bell of them* 95 ffcarlet oker, terra de fienna, terra verte, true Indian red and umbre in oil painting, and hiffye and gall ftones in water pwatiag* we, either through their fcarcity, or the {ignorance which prevails concerning their qualities, at. prefent very little regarded; though fbme of them were formerly in common ufe; and all of them might ho, ft with great advantage to the. art,
It is no little impediment to their improve- a ment in the profefiion, that, painters are not more extenfively acquainted with all the fub- ftances fit for their purpofes x and more minutely informed of the good a$ well >s the bad qualities of what colours they might ufe: for m3ny-labour under great difadvarttages-for* want of a 'copious choice, and the net being better apprized of feme of thofe which fek thei? own particular manner of woekingj and which would, in many cafes, remove difficult ties out of their way, by enabling them to pro- duce effects by more fimple methods, and luch as arc yet more corvefoondeqt to their manner, than tnofc they are now obliged to perfue from their defed: of proper colours.
As colours are obtained from very various fub- ftanccs, the means qf preparing them are, eon- fequently, very various : feme being of a Ample nature, and requiring only to be purified, and reduced to a proper confidence or texture; and others being compounds of different bo- flies, to be formed only by complex and elaborate precedes, h is therefore very difficult fo give fiich general directions, for the making every fort of colour, as may be intelligible to all; the utenfils to be employed, as well as the methods to be perfued, being fuch as belong to different art^ and trades: bqt at foe greater part may be done pioft comipodioufly by adopting the methods ufed % performing the commop chemical proeefies, k is the moft expedient way to treat of them correjpqndently to fuch a view: as, by that means, any whp may make themfefves acquainted with foe common praChce of chemiftry, for which there arq a number of books that Afford fufficient affifo* ance, may eafily underftand the whole art of making colours whe,p taught in fois manner; For foe fake, however, of foofe, \eho m?y want leifure or difjxjfitlon to proceed by this method, I will prefix fbtfo a defcfiptlqn qf thq ipftrumcptSj and explanation of' foe general
* * nature of die operations, as together with the particular directions given in each procels, may enable even fuch as are wholly ignorant of chemiftry, if they give a due attention, to get over this difficulty: as indeed, without fuch a previous knowledge of the nature of .the in- itruments and operations, it would be impracticable to attempt to. prepare feveral of the moll valuable colours.:
Where, nevertheleft, limple means, and the ufe of liich utenlils as are generally known, may be Sufficient to perform what is wanted ; I mall avoid all technical terms, and more complex methods of operation; confining my* folf to fuch a manner , of inllruCtion, as may be univerfally intelligible.