CHAPTER XIV._Pigments, Paint and Painting: A practical book for practical men

PAINTING.

The successful application of paint, whether for artistic or

preservative purposes, necessitates careful attention to a number of

considerations, some of a mechanical and others of a chemical character.

_The Surface._--Of whatever the surface may be to which the paint is

to be applied, great care must be taken that it is perfectly dry. Wood

especially, even when apparently dry, may on a damp day contain as much

as 20 per cent. of moisture. A film of paint applied to the surface

of wood in this condition prevents the moisture from escaping, and it

remains enclosed until a warm sun or artificial heat converts it into

vapour, which raises the paint and causes blisters. Moisture enclosed

between two coats of paint has the same effect. Paint rarely blisters

when applied to wood from which old paint has been burnt off; this is

probably due to the drying of the wood during the operation of burning.

When the surface to be painted is already covered with old paint, this

should be either removed or rubbed down smooth before applying the

new. When the thickness of the old coat is not great, rubbing down,

accompanied by a careful scraping of blisters and defective parts,

will suffice. When the thickness of the old paint necessitates its

removal, it may either be burned off, or softened by a solution of

caustic alkali, and afterwards scraped. The burning process is the

most effective, and leaves the wood in a fit condition to receive the

fresh coat of paint; but it is not applicable in the case of fine

mouldings. When caustic potash or soda is used, the paint is left in

contact with, it for some time, when the linoleic acid of the oxidised

linseed-oil becomes saponified, and can easily be scraped or scrubbed

off the surface of the wood.

Whenever an alkali is employed, it is of the greatest importance that

the wood should afterwards be thoroughly washed several times with

clean water, in order to remove every trace of the solvents. Any soda

or potash remaining in the pores of the wood would not only retain

moisture and cause blistering, but would also have an injurious action

upon the vehicle of the paint subsequently applied, and in many cases

upon the pigment itself. The remarks already made as to the necessity

of an absolutely dry surface should be borne in mind in this instance.

When the surface of the paint is to be protected by a coat of varnish,

the latter should not be applied until the whole of the oil contained

in the paint has solidified. The wrinkling of varnish upon paint is

frequently erroneously attributed to the bad quality of the varnish,

when the real cause is the incomplete oxidation of the paint itself.

_Priming._--The first coat of paint applied to any surface is termed

the “priming-coat.” It usually consists of red lead and boiled and raw

linseed-oil. Experience has shown that such a priming not only dries

quickly itself, but also accelerates the drying of the next coat. The

latter action must be attributed to the oxygen contained in the red

lead, only a small portion of which is absorbed by the oil with which

it is mixed.

Kali, of Heidelberg, prepares a substitute for boiled oil by mixing 10

parts whipped blood, just as it is furnished from the slaughter-houses,

with 1 part of air-slaked lime sifted into it through a fine sieve.

The two are well mixed and left standing for 24 hours. The dirty

portion that collects on top is taken off, and the solid portion is

broken loose from the lime at the bottom; the latter is stirred up with

water, left to settle, and the water is poured off after the lime has

settled. The clear liquid is well mixed up with the solid substance

before mentioned. This mass is left standing for 10 or 12 days, after

which a solution of potash permanganate is added, which decolorises it

and prevents putrefaction. Finally the mixture is stirred up, diluted

with more water to give it the consistence of very thin size, filtered,

a few drops of oil of lavender are added, and the preparation is

preserved in closed vessels. It is said to keep a long time without

change. A single coat of this liquid will suffice to prepare wood or

paper, as well as lime or hard plaster walls, for painting with oil

colours. This substance is cheaper than linseed oil, and closes the

pores of the surface so perfectly that it takes much less paint to

cover it than when primed with oil.

_Drying._--The drying of paint is to a great extent dependent upon the

temperature. Below the freezing point of water, paint will remain wet

for weeks, even when mixed with a considerable proportion of dryers;

while, if exposed to a heat of 120° F. the same paint will become solid

in a few hours. The drying of paint being a process of oxidation, and

not evaporation, it is essential that a good supply of fresh air should

be provided. When a film of fresh paint is placed with air in a closed

vessel, it does not absorb the whole of the oxygen present; but after a

time the drying process is arrested, and the remaining oxygen appears

to have become inert.

Considerable quantities of volatile vapours are given off during the

drying of paint; these are due to the decomposition of the oil. When

the paint has been thinned down by turpentine, the whole of this

liquid evaporates on exposure to the air. There must, therefore, be

a plentiful access of air, to remove the vapours formed, and afford

a fresh supply of active oxygen. The presence of moisture in the air

is rather beneficial than injurious at this stage. Especially in the

case of paints mixed with varnish, moist air appears to counteract the

tendency to crack or shrink. Under the erroneous impression that the

drying of paint is a species of evaporation, open fires are sometimes

kept up in freshly-painted rooms. It is only when the temperature is

very low that any benefit can result from this practice; as a rule, it

rather retards than hastens the solidification of the oil, which cannot

take place rapidly in an atmosphere laden with carbonic acid.

The first coat of paint should be thoroughly dry before the second is

applied. Acrylic acid is formed during the oxidation of linseed-oil,

and unless this be allowed to evaporate, it may subsequently liberate

carbonic acid from the white lead present in most paints, and give rise

to blisters. Sometimes a second priming-coat is given; but usually

the second coat applied contains the pigment. This, as soon as dry,

is again covered by another coat, and subsequently by two or more

finishing coats, according to the nature of the work.

_Filling._--Before the first coat is applied to wood, all holes should

be filled up. The filling usually employed is ordinary putty; this,

however, sometimes consists of whiting ground up with oil foots of a

non-drying character, and when the films of paint are dry, the oil from

the putty exudes to the surface, causing a stain. The best filling for

ordinary purposes is whiting ground to a paste with boiled linseed-oil.

For finer work, and for filling cracks, red lead mixed with the same

vehicle may be employed. For porous hard woods, use boiled oil and

corn starch stirred into a very thick paste; add a little japan, and

reduce with turpentine. Add no colour for light ash; for dark ash and

chestnut, use a little raw sienna; for walnut, burnt umber and a slight

amount of Venetian red; for bay wood, burnt sienna. In no case use

more colour than is required to overcome the white appearance of the

starch, unless you wish to stain the wood. This filler is worked with

brush and rags in the usual manner. Let it dry 48 hours, or until it

is in condition to rub down with No. 0 sand-paper without much gumming

up; and if an extra fine finish is desired, fill again with the same

materials, using less oil, but more japan and turpentine. The second

coat will not shrink, being supported by the first. When the second

coat is hard, the wood is ready for finishing up by following the usual

methods. This formula is not intended for rosewood.

_Coats._--There is no advantage in laying on the paint too thickly.

A thick film takes longer to dry thoroughly than two thin films of

the same aggregate thickness. Paint is thinned down or diluted with

linseed-oil or turpentine. The latter liquid, when used in excess,

causes the paint to dry with a dull surface, and has an injurious

effect upon its stability. Sometimes the last coat of paint is mixed

with varnish, in order to give it greater brilliancy. In this case,

special care must be taken that the previous coats have thoroughly

solidified, or cracks in the final coat may subsequently appear. The

same remark applies when the surface of the paint is varnished. The

turpentine with which the varnish is mixed has a powerful action

upon the oil contained in the paint, if the latter is not thoroughly

oxidised. The exterior of the paint is thus softened, and the varnish

is enabled to shrink and crack, especially in warm weather.

_Brushes._--The bristles are frequently fastened by glue or size, which

is not perceptibly acted upon by oil, and if brought into contact with

this liquid alone, there would be no complaints of loose hairs coming

out and spoiling the work. It is a common practice to leave the brushes

in a paint-pot, in which the paint is covered with water to keep it

from drying. The brushes are certainly kept soft and pliant in this

way; but at the same time the glue is softened, and the bristles come

out as soon as the brush is used. After use, brushes should be cleaned,

and placed in linseed-oil until again required, when they will be found

in good condition. Treated in this way, they will wear so much better

that the little additional trouble entailed is amply repaid. When

brushes will not again be required for some time, the oil remaining in

them should be washed out by means of turpentine, after which they may

be dried without deterioration. On no account should oil be allowed

to dry in a brush, as it is most difficult to remove after oxidation

has taken place. The best means are steeping in benzoline for a few

days, or in turpentine, with occasional washing in soda-water and with

soft-soap, avoiding too violent rubbing.

_Water-colours._--The manufacture of water-colour paints is more simple

than that of oil paints, the pigments being first ground extremely

fine and then mixed with a solution of gum or glue. The paste produced

in this manner is allowed to dry, after having been stamped into the

form of cakes. As soon as the hardened mass is rubbed down with water,

the gum softens and dissolves, and if the proportion of water be not

too great, the pigment will remain suspended in the solution of gum,

and can be applied in the same manner as oil-paint. To facilitate the

mixing with water, glycerine is sometimes added to the cake of paint,

which then remains moist and soft.

_Removing Odour._--(1) Place a vessel of lighted charcoal in the room,

and throw on it 2 or 3 handfuls of juniper berries; shut the windows,

the chimney, and the door close; 24 hours afterwards the room may be

opened, when it will be found that the sickly, unwholesome smell will

be entirely gone. (2) Plunge a handful of hay into a pail of water, and

let it stand in the room newly painted.

_Discoloration._--Light-coloured paints, especially those having white

lead as a basis, rapidly discolour under different circumstances. Thus

white paint discolours when excluded from the light; stone colours lose

their tone when exposed to sulphuretted hydrogen, even when that is

only present in very small quantity in the air; greens fade or darken,

and vermilion loses its brilliancy rapidly in a smoky atmosphere like

that of London.

Ludersdorf thinks that the destructive change is principally due to

a property in linseed-oil which cannot be destroyed. The utility of

drying oils for mixing pigments depends entirely on the fact that

they are converted by the absorption of oxygen into a kind of resin,

which retains the colouring pigment in its semblance; but during

this oxidation of the oil--the drying of the paint--a process is set

up which, especially in the absence of light and air, soon gives

the whitest paint a yellow tinge. Ludersdorf therefore proposes

to employ an already formed but colourless resin as the binding

material of the paint, and he selects two resins as being specially

suitable--one, sandarach, soluble in alcohol; the other, dammar,

soluble in turpentine. The sandarach must be carefully picked over, and

7 oz. is added to 2 oz. Venice turpentine and 24 oz. alcohol of sp.

gr. 0·833. The mixture is put in a suitable vessel over a slow fire

or spirit-lamp, and heated, stirring diligently, until it is almost

boiling. If the mixture be kept at this temperature, with frequent

stirring for an hour, the resin will be dissolved, and the varnish is

ready for use as soon as cool. The Venice turpentine is necessary to

prevent too rapid drying, and more dilute alcohol cannot be employed,

because sandarach does not dissolve easily in weaker alcohol, and,

furthermore, the alcohol, by evaporation, would soon become so weak

that the resin would be precipitated as a powder.

When this is to be mixed with white lead, the latter must first be

finely ground in water, and dried again. It is then rubbed with a

little turpentine on a slab, no more turpentine being taken than is

absolutely necessary to enable it to be worked with the muller; 1 lb.

of the white lead is then mixed with exactly ½ lb. of varnish, and

stirred up for use. It must be applied rapidly, because it dries so

quickly. If when dry the colour is wanting in lustre, it indicates the

use of too much varnish. In such cases, the article painted should be

rubbed, when perfectly dry, with a woollen cloth to give it a gloss.

The dammar varnish is made by heating 8 oz. dammar in 16 oz. turpentine

oil at 165° to 190° F., stirring diligently, and keeping it at this

temperature until all is dissolved, which requires about an hour. The

varnish is then decanted from any impurities, and preserved for use.

The second coat of the pure varnish, to which half its weight of oil of

turpentine has been added, may be applied. It is still better to apply

a coat of sandarach varnish made with alcohol, because dammar varnish

alone does not possess the hardness of sandarach, and when the article

covered with it is handled much, does not last so long.

_Composition._--The composition of paints should be governed--

(1) By the nature of the material to be painted: thus the paints

respectively best adapted for wood and iron differ considerably.

(2) By the kind of surface to be covered: a porous surface requires

more oil than one that is impervious.

(3) By the nature and appearance of the work to be done: delicate tints

require colourless oil, a flatted surface must be painted without oil

(which gives gloss to a shining surface), paint for surfaces intended

to be varnished must contain a minimum of oil.

(4) By the climate and the degree of exposure to which the work will be

subjected: for outside work, boiled oil is used, because it weathers

better than raw oil; turps is avoided as much as possible, because it

evaporates and does not last; if, however, the work is to be exposed to

the sun, turps is necessary, to prevent the paint from blistering.

(5) The skill of the painter affects the composition: a good workman

can lay on even coats with a smaller quantity of oil and turps than

one who is unskilful; extra turps, especially, are often added to save

labour.

(6) The quality of the materials makes an important difference in the

proportions used: thus more oil and turps will combine with pure than

with impure white lead; thick oil must be used in greater quantity than

thin when paint is purchased ready ground in oil, a soft paste will

require less turps and oil for thinning than a thick.

(7) The different coats of paint vary in their composition: the first

coat laid on to new work requires a good deal of oil to soak into the

material; on old work, the first coat requires turpentine to make it

adhere; the intermediate coats contain a proportion of turpentine to

make them work smoothly; and to the final coats the colouring materials

are added, the remainder of the ingredients being varied according as

the surface is to be glossy or flat.

The exact proportions of ingredients best to be used in mixing paints

vary according to their quality, the nature of the work required,

the climate, and other considerations. The composition of paint for

different coats also varies considerably. The proportions given in the

following table must only be taken as an approximate guide when the

materials are of good quality:--

TABLE showing the COMPOSITION of the different

COATS of WHITE PAINT, and the QUANTITIES

required to cover 100 yd. of NEWLY-WORKED PINE.

--------------+-----+-------+------+------+-----+------+---------

| | | oil | oil | | |footnotes)

--------------+-----+-------+------+------+-----+------+---------

4 coats not | | | | | | | [A]

flatted._ | lb. | lb. | pt. | pt. | pt. | lb. |

| | | | | | |

Priming | ½ | 16 | 6 | -- | -- | ¼ |

2nd coat | [B] | 15 | 3½ | -- | 1½ | ¼ |

3rd coat | -- | 13 | 2½ | -- | 1½ | ¼ |

4th coat | -- | 13 | 2½ | -- | 1½ | ¼ |

| | | | | | |

Priming |1½ | 16 | 6 | -- | ½ | 1-8 |

2nd coat | -- | 12 | 4 | -- | 1½ | 1-10|

3rd coat | -- | 12 | 4 | -- | 0 | 1-10|

4th coat | -- | 12 | 4 | -- | 0 | 1-10|

Flatting | -- | 9 | 0 | -- | 3½ | 1-10|

| | | | | | |

_Outside work | | | | | | | [C]

Priming | 2 | 18½ | 2 | 2 | -- | 1-8 |

2nd coat | -- | 15 | 2 | 2 | ½ | 1-10|

3rd coat | -- | 15 | 2 | 2 | ½ | 1-10|

4th coat | -- | 15 | 3 | 2½ | 0 | 1-10|

---------------------------------------------------------------

[A] Sometimes more red lead is used and less dryer.

[B] Sometimes just enough red lead is used to give a flesh-coloured

tint.

[C] When the finished colour is not to be pure white, it is better to

have nearly all the oil boiled oil. All boiled oil does not work well.

For pure white a larger proportion of raw oil is necessary, because

boiled oil is too dark.

_Area Covered._--For every 100 sq. yd., besides the material enumerated

in the foregoing, 2½ lb. white lead and 5 lb. putty will be required

for stopping. The area which a given quantity of paint will cover

depends upon the nature of the surface to which it is applied, the

proportion of the ingredients, and the state of the weather. When the

work is required to dry quickly, more turpentine is added to all the

coats. In repainting old work, two coats are generally required, the

old paint being considered as priming. Sometimes another coat may

be deemed necessary. For outside old work exposed to the sun, both

coats should contain 1 pint turpentine and 4 pints boiled oil, the

remaining ingredients being as stated in the foregoing table. The

extra turpentine is used to prevent blistering. In cold weather, more

turpentine should be used to make the paint flow freely.

According to another authority, it is found that in painting wood,

one coat takes 20 lb. lead and 4 gal. oil per 100 sq. yd.; the second

coat, 40 lb. lead and 4 gal. oil; and the third the same as the second;

say 100 lb. lead and 16 gal. oil per sq. yd. for the three coats. The

number of square yards covered by one gallon of priming colour is found

to be 50; of white zinc, 50; of white lead paint, 44; of lead colour,

50; of black paint, 50; of stone colour, 44; of yellow paint, 44; of

blue colour, 45; of green paint, 45.

_Measuring._--Surface painting is measured by the superficial yard,

girting every part of the work covered, always making allowance for

the deep cuttings in mouldings, carved work, railings, or other work

that is difficult to get at. Where work is very high, and scaffolding

or ladders have to be employed, allowances must be made. The

following rules are generally adopted in America in the measurement

of work:--Surfaces under 6 in. in width or girt are called 6 in.;

from 6 to 12 in., 12 in.; over 12 in., measured superficial. Openings

are deducted, but all jambs, reveals, or casings are measured girt.

Sashes are measured solid if more than two lights. Doors, shutters and

panelling are measured by the girt, running the tape in all quirks,

angles or corners. Sash doors measure solid. Glazing, in both windows

and doors, is always extra. The tape should be run close in over the

battens, on batten doors, and if the stuff is beaded, add 1 in. in

width for each bead. Venetian blinds are measured double. Dentels,

brackets, medallions, ornamented iron work, balusters, lattice work,

palings, or turned work, should all be measured double. Changing

colours on base boards, panels, cornices, or other work, one-fourth

extra measurement should be allowed for each tint. Add 5 per cent. to

regular price for knotting, puttying, cleaning, and sand-papering. For

work done above the ground floor, charge as follows:--Add 5 per cent.

for each story of 12 ft. or less, if interior work; if exterior work,

add 1 per cent. for each foot of height above the first 12 ft.

CARRIAGE AND CAR PAINTING.--The following is the substance of

an address delivered by McKeon, secretary and treasurer of the Master

Car-Painters’ Association of the United States:--A first-class railway

coach costs, when complete, about 1200_l._ To protect this work, the

painter expends 60_l._ to 120_l._ The latter figure will make a first

class job. The car has been completed in the wood-shop, and is turned

over to the painter, who is responsible for the finish. He is expected

to smooth over all rough places or defects in the wood, which requires

both patience and skill to make the work look well. Twelve weeks should

be the time allowed to paint a car, and it cannot be done in any less

time, to make a good job that will be a credit to the painter and all

other parties interested in the construction and finish of the car. Too

much painting is done in a hurry: proper time is not given the work to

dry or become thoroughly hardened before it is run out of the shop, and

consequently it does not always give the satisfaction it should; nor

can it be expected that hurried work will be so lasting or durable as

that which has the necessary time given to finish it.

_Priming Paint._--The priming coat of paint on a car is of as much

importance as any succeeding one, and perhaps more. Good work is ruined

in the priming by little or no attention being given by the painter to

the mixing and application of the first coat. The foundation is the

support, and on that rests success or failure. The priming should be

made of the proper material, mixed with care from good lead and good

oil, and not picked up from old paints which have been standing mixed,

and must necessarily be fat and gummy, for such are unfit for use on

a good job, and will have a decided tendency to spoil the whole work.

Special care should be exercised, both in mixing and applying the

priming, and it should be put on very light, so that it may penetrate

well into the wood. Too much oil is worse than not enough. Good ground

lead is by far the best material for the undercoats on a car. Two coats

should be given to the car before it is puttied, as it is best to fill

well with paint the nail-holes and plugs, as well as defects in the

wood, so that moisture may not secure a lodgment, which otherwise will

cause the putty to swell, although sometimes unseasoned lumber will

swell the putty; and as it shrinks, the nail remains stationary, and of

course the putty must give way.

_Best Putty._--In mixing putty, which may be a small matter with some,

take care to so prepare it that it will dry perfectly hard in 18 hours.

Use ground lead and japan, stiffening up with dry lead, and whatever

colouring you may require in it to match your priming coats.

The next coats, after the work is well puttied, should be made to dry

flat and hard. Two coats should be applied, and, for all ordinary

jobs or cheap work, sand-papering is all that is necessary for each

coat; but when a good surface is required, I would recommend one coat

to be put on heavy enough to fill the grain; and before being set,

scrape with a steel scraper. The plain surface is all that requires

coating and scraping with the heavy mixture. For this coat, which is

called filling, use one-half ground lead and any good mineral which

experience has shown can be relied on. This scraping of the panel work

will fill the wood equal to two coats of rough stuff, and saves a great

amount of labour over the old process, when so much rubbing with lump

pumice was done. Sand-paper when the filling is thoroughly hard, and

apply another coat of paint of ordinary thickness, when, after another

sand-papering, you have a good surface for your colour.

Rough-coating on cars has gone almost out of use, and few shops are now

using it to any extent. My experience is that paint has less tendency

to crack where rough stuff is left off. I do not claim that the filling

was the principal cause of the cracking, if it was properly mixed; but

I believe the water used in rubbing down a car with the lump pumice

injures the paint, as it will penetrate in some places, particularly

around the moulding plugs.

_Finishing Colour._--The car being ready for the finishing colour, this

should be mixed with the same proportion of dryer as the previous coat,

or just sufficient to have it dry in about the same time. A great error

with many car painters is using a large portion of oil in the under

coats, and then but little, if any, in the finishing coats; this has a

decided tendency to crack, the under coats being more elastic. Always

aim to have colour dry in about the same time, after you have done

your priming; by this plan you secure what all painters should labour

to accomplish--namely, little liability to crack. Work will of course

crack sometimes after being out a few months, or when it has repeated

coatings of varnish; and using a quick rubbing varnish on work will

cause it to give way in fine checks quicker than anything else. Many of

the varnishes used are the cause of the paint cracking, and no painter

has been wholly exempt from this trouble.

_Cause of Cracking._--The most common cause of cracking is poor japan,

which is the worst enemy that the car-painter has to contend with. The

greater part of the japan is too elastic, and will dry with a tack,

and the japan gold size has generally the same fault, although the

English gold size is generally of good quality; but its high price

is an objection to its use. A little more care in the manufacture

of japans would give a better dryer, and few would object to the

additional cost. Japan frequently curdles in the paint; it will not mix

with it, but gathers in small gummy particles on the top. Work painted

with such material cannot do otherwise than crack and scale, and the

remedy lies only in getting a good pure article of turpentine japan.

In regard to using ground lead, car-painters differ, as some prefer

to grind their own in the shop. I use the manufactured lead, and my

reasons for doing so are that it is generally finer than any shop can

grind it with present facilities, and it has age after grinding, which

improves its quality. You can also get a purer lead and one with more

body than you can by grinding in the shop, which is a fact that I think

most painters must admit. I have tested it very fully, and am convinced

on this point.

_Mixing the Paints._--Permit me to make a few suggestions here in

regard to the mixing of paint, which may not fully agree with others’

views. There is just as much paint that cracks by putting it on too

flat as by using too much oil. Some painters mix their finishing colour

so that it is impossible to get over a panel of ordinary size before

it is set under the brush, and consequently the colour will rough up.

Colour should be mixed up so that it will not flat down for some time

after leaving it, and then you have got some substance that will not

absorb the varnish as fast as it is applied to the surface. This quick

drying of colour is not always caused by want of oil in it, but because

there is too much japan, and a less quantity of the latter will do

better work, and make a smoother finish. Give your colour 48 hours to

dry between coats; always give that time, unless it is a hurried job,

and experience has fully demonstrated that it is poor economy to hurry

work out of the shop before it is properly finished.

_Oils, Dryers, and Colours._--In car-painting, both raw and boiled oils

are used, and good work may be done with either, but I recommend oil

that is but slightly boiled, in preference to either the raw or the

boiled. After it is boiled, if it is done in the shop, let it stand

24 hours to settle, then strain off carefully; this takes out all the

impurities and fatty matter from the oil, and it will dry much better,

nor will it have that tack after drying that you find with common

boiled oil. Use the proper quantity of dryer in mixing your paint,

and a good reliable job will be the result. In car-painting, never

use prepared colours which are ground in oil, as nine-tenths of such

colours are ground in very inferior oil, and they may have been put up

for a great length of time, in which case they become fatty, and will

invariably crack. These canned colours do not improve with age, as lead

and varnish do.

Finishing colours should all be ground in the shop, unless special

arrangements can be made with manufacturers to prepare them; and the

colour should be fresh, not over 6 or 8 days old after being mixed,

and open to the air. Enough may be prepared at a time to complete the

coating on a job; but when colour stands over a week it is not fit to

use on first-class work, as it becomes lifeless, and has lost that

free working which we find in freshly-mixed colours. Such colour may,

however, be used upon a cheap class of work, or on trucks, steps, &c.,

so that nothing need be wasted in the shop.

_Varnishing._--Three coats of varnish over the colour are necessary on

a first-class coach. The first coat should be a hard drying varnish

put on the flat colour; the quick rubbing that some use I would not

recommend, but one that will dry in five days (in good drying weather)

sufficiently hard to rub, is the best for durability. After striping

and ornamenting the car, and when thoroughly washed, give a coat of

medium dry varnish. Let this stand 8 days; then rub lightly with curled

hair or fine pumice, and apply the finishing coat, which is “wearing

body;” this will dry hard in about 10 days, after which the car may

be run out of the shop. It should then be washed with cold water and

a soft brush, and is ready for the road. In varnishing, many will

apply the varnish as heavy as they can possibly make it lie, when, as

a consequence, it flows over and runs or sags down in ridges, and of

course does not harden properly; this also leaves a substance for the

weather to act on. It is better to get just enough on at a coat to make

a good even coating which will flow out smooth, and this will dry hard,

and will certainly wear better than the coat that is piled on heavily.

Varnishing, we claim, can be over-done, despite some painters’ opinions

to the contrary. We have heard of those who put 2½ gal. on the body

of a 50-foot car at one application, and we have also listened to the

declaration, made by a member of the craft, that he put 2 gal. on the

body of a locomotive tank. Such things are perhaps possible, and may

have been done; but if so, we know that the work never stood as well as

it would if done with one-half the quantity to a coat. In varnishing

a car, care should be taken to have the surface clean; water never

injures paint where it is used for washing; and a proper attention

to cleanliness in this respect, and in the care of brushes used for

varnishing, will ensure a good-looking job.

Perhaps your shop facilities for doing work are none of the best, but

do the best you can with what you have. Select if possible, a still,

dry day for varnishing, especially for the finishing coat. Keep your

shop at an even temperature; avoid cold draughts on the car from doors

and windows; wet the floor only just sufficient to lay the dust, for

if too wet, the dampness arising will have a tendency to destroy the

lustre of your varnish. Of course we cannot always do varnishing to our

perfect satisfaction, especially where there are 25 or 30 men at work

in an open shop, and 6 or 8 cars are being painted, when more or less

dirt and dust are sure to get on the work.

A suggestion might here be made to railroad managers, which is that

no paint-shop is complete where the entire process of painting and

finishing a car is to be done in one open shop. A paint-shop should

be made to shut off in sections by sliding doors, one part of the

shop being used exclusively for striping and varnishing. I know from

experience that nine-tenths of the railroad paint-shops are deficient

in this particular, and still we are expected to turn out a clean job,

no matter what difficulties we are compelled to labour under.

_Importance of Washing Cars._--In regard to the care of a car after it

has left the shop, more attention should be given to this than is done

on many roads. The car should not be allowed to run until it is past

remedy, and the dirt and smoke become imbedded in the varnish, actually

forming a part of the coating, so that when you undertake to clean the

car you must use soda or soap strong enough to cut the varnish before

you succeed in removing the dirt. Cars should be washed well with a

brush and water at the end of every trip. This only will obviate the

difficulty, and these repeated washings will harden the varnish as well

as increase its lustre. We know that, in washing a car, where soap is

required to remove the dirt and smoke, it is almost impossible to get

the smoke washed off clean; and if it is not quite impossible, the hot

sun and rain will act on the varnish and very soon destroy it.

_Re-varnishing._--Cars should be taken in and re-varnished at least

once in 12 months; and if done once in 8 months it is better for them,

and they will require only one coat; but where they run a year, they

will generally need two coats. Those varnished during the hot months

will not stand as well as if done at any other time. Painting done in

extremely cold weather, or in a cold shop, is more liable to crack than

if done in warm weather.

_How to Dry Paint._--Paint dried in the shop where there is a draught

of dry air passing through, will stand better than that dried by

artificial heat; and you will find, by giving it your attention, that

work which has failed to stand, and which cracked or scaled, was

invariably painted in the winter season, or in cool, wet weather. I

have paid some attention to this matter, and know the result.

WOODWORK PAINTING.--One of the attendant drawbacks of houses

that are newly built, or have been hastily finished for letting, is

the inferior painting of the woodwork, and its speedy destruction. The

wood is not thoroughly dry, and the consequence is the preparatory coat

does not adhere; the pores being full of dampness, it is impossible for

the oil to sink into them, especially as oil and water are unmiscible.

Another equally injurious condition is the gum-resin which exudes from

the knots of new pine and other timber. Painted over before it has

time to come to the surface, the coat is destroyed by the action of

the gum. Now, these evils have to be endured so long as the wood has

no time to get seasoned. The painter follows the carpenter without any

interval of time, and before the action of the weather can bring out

the moisture and resinous substances. A coating of shellac is usually

given to the knots, though this is often so thin as to be worthless.

Crude petroleum, as a preservative coat, is found to be an admirable

preparation for the painting. The petroleum is thin, and penetrates the

wood, filling up the pores, and giving a good ground for the coats of

paint.

According to one American authority, the preparation is of great value.

The priming coat should be thin and well rubbed in, and it is better

to use a darker colour than white lead as a base. White lead forms a

dense covering to the surface, though it has its disadvantages. When

petroleum has formed the first coat, two other coats will suffice,

one being the priming coat, and a third coat may be given after the

work has stood for a season. It is a very desirable plan to leave

the painting, or rather finishing coats, for a time, so that any

imperfections in the wood or work may be discovered; it also allows

time for any change of colour that may be made. After the priming

coat, it is usual in good work to stop all cracks, nail-holes, and

other defects with putty; but in the commoner class of paintings, the

coats are laid on quickly, the preceding coat has hardly time to dry

before the next is put on, and all the defects of wood, bad seasoning,

exudation of gum, &c., quickly begin to show themselves through and

disfigure the work.

A good paint ought to possess body, power of covering, and flow evenly

from the brush, and become hard. Though zinc white has less body than

white lead, it is more durable, and will stand sulphur acids without

blackening. Some colours stand better than others; the ochres, Indian

and Venetian reds, burnt and raw umber, are reliable, and may be

used without scruple. It is also worthy of notice that salt air acts

injuriously on white lead, and zinc white is therefore preferable in

situations exposed to the sea-air. (_English Mechanic._)

IRON PAINTING.--The decay of iron becomes very marked in

certain situations, and weakens the metal in direct proportion to the

depth to which it has penetrated; and although where the metal is in

quantity this is not very appreciable, it really becomes so when the

metal is under ¾ inch in thickness. The natural surface of cast iron is

very much harder than the interior, occasioned no doubt by its becoming

chilled, or by its containing a large quantity of silica, and this

affords an excellent protection.

But should this surface be at all broken, rust immediately attacks

the metal and soon destroys it. It is very desirable that the casting

be protected, and a priming coat of oil or paint should be applied

for this purpose; the other coats, though requisite, can be given at

leisure.

The following is a process to which all cast-iron water pipes should be

submitted. It was introduced by Dr. Smith, and is equally applicable to

any other casting that can be manipulated:--Each casting is thoroughly

dressed, and made clean and free from the earth and sand which cling

to the iron in the moulds, hard brushes being used in finishing the

process to remove the loose dust. Every casting must be likewise free

from rust when the paint is applied. If the casting cannot promptly be

dipped after being cleansed, the surface must be oiled with linseed oil

to preserve it until it is ready to be dipped. No casting is on any

account to be dipped after rust has set in. The coal-tar pitch used

as a paint in this process is made from coal-tar distilled until the

naphtha is entirely removed and the material is deodorised. In England

it is distilled until the pitch is about the consistence of wax. The

mixture of 5 or 6 per cent. of linseed oil is recommended by Dr. Smith.

Pitch which becomes hard and brittle when cold will not answer for

this use. Pitch of the proper quality having been obtained, it must be

carefully heated in a suitable vessel to a temperature of 300° F., and

must be maintained at not less than this temperature during the time

of dipping. The material will thicken, and deteriorate after a number

of pieces have been dipped; fresh pitch must, therefore, frequently be

added, and occasionally the vessel must be entirely emptied of its old

contents and refilled with fresh pitch. The refuse will be hard and

brittle like common pitch, and consequently worthless for the purpose.

Every casting must attain a temperature of 300° F., either by previous

heating or during the immersion before being removed from the vessel of

hot pitch. It may then be slowly removed, and laid upon skids to drip.

In the case of water pipes, all those of 20 inches diameter and upwards

will have to remain at least 30 minutes in the hot fluid to attain this

temperature. The coating when cold should be tough and tenacious, and

not brittle nor have the slightest tendency to scale off.

In considering the painting of wrought iron it must be noticed that

when iron is oxidised by heating in contact with the atmosphere, two

or three distinct layers of scale form on the surface, and, unlike

the skin upon cast iron, can be readily detached, as by bending or by

hammering the metal. The outer layer of this scale is more highly

oxidised than the inner, and is slightly redder in tinge from the

presence of a variable excess of ferric oxide over that contained in

the inner layer. The oxide occurring in the outer scale is fusible only

at a high temperature, is strongly magnetic, and slightly metallic in

lustre; while the inner layers are more porous, dull, and non-metallic

in lustre, less brittle, and also less powerfully magnetic. It will be

seen that the iron has a tendency to rust from the moment it leaves the

hammer or rolls, and that the scale above described must come away. One

of the plans to preserve the iron has been to coat it with paint when

still hot at the mill; and although this answers for a while, it is

a very troublesome method, which iron-masters cannot be persuaded to

adopt, and the subsequent cutting processes to which it is submitted

leave many parts of the iron bare. Besides, a good deal of the scale

remains, and until this has fallen off, or has been removed, any

painting over it will be of little value. The only effectual way of

preparing wrought iron is to effect a thorough and chemical cleansing

of the surface of the metal upon which the paint is to be applied, that

is, it must be immersed for three or four hours in water containing

from 1 to 2 per cent. of sulphuric acid. The metal is afterwards rinsed

in cold water, and, if necessary, scoured with sand, put again into the

acid bath or pickle, and then well rinsed.

The real value of any paint depends upon the quality of the linseed

oil, the quality and character of the pigment, and the care bestowed

on the grinding and mixing, and as all this is entirely a matter of

expense, cheap paints are not to be relied upon. The superiority of

most esteemed paints is due to the above causes rather than to any

unknown process or material employed in the manufacture.

The following excellent article on the preservation of iron and steel

structural work appeared in the ‘Illustrated Carpenter and Builder.’ It

conveys the most recent American opinion.

One of the most important economic questions of the present day is the

preservation of iron and steel structures. In America many millions of

dollars are annually spent in the erection and construction of these,

and the amount is increasing in rapid proportion. Bridges, buildings,

viaducts, ships, and machinery are now being made of these materials,

to almost the entire exclusion of others. From their very nature iron

and steel are peculiarly subject to decay from atmospheric and other

influences. The question of preserving them is not merely one of

finance, but, especially in the case of railroads, one affecting the

lives and property of a large portion of the community. What, then, is

the best method of preserving them?

The almost universal method is by means of paints, or the application

of substances to their surfaces which will resist or retard the

influence of air, water, and other destructive agencies. The requisites

of a good paint for this purpose are that it shall adhere firmly to

the surface, and not chip or peel off, thereby leaving portions of

the surface exposed. It must not corrode the iron, else the remedy

may only aggravate the disease. It must form a surface hard enough to

resist influences which would remove it by friction, yet elastic enough

to conform to the expansion and contraction of the metal by heat and

cold. It must be impervious to and unaffected, as far as possible, by

moisture, atmospheric and other influences to which the structure may

be exposed.

The paints that have been used for this purpose are principally asphalt

and coal-tar paints, consisting of mineral and artificial asphalt or

coal-tar, either applied alone or combined with each other, and, more

or less, with metallic bases, and iron oxide paints and lead oxide

paints, especially red lead, in all of which the pigment is held to

the surface of the iron or steel by combination with linseed oil. The

choice of paints must lie, so far as our present practical experience

goes, between these three classes, zinc oxide being found to be

entirely unsuitable on account of a propensity to peel off. What,

then, is found to be the experience in actual practice with these?

Asphalt and coal-tar paints “run” when exposed to the sun and other

sources of heat, which is a serious matter with vertical surfaces;

and after a time become extremely brittle and scale off entirely,

leaving the under surface exposed, unless the paint is constantly

renewed. In the meantime the exposed iron and steel are being corroded

by rust. Iron oxide paints, including “metallic brown,” are paints

made from iron ore, or by some chemical process with an iron base.

These are invariably iron in a greater or less degree of oxidation,

or in other words, rusted iron. Now it is well known that one of the

most active promoters of rust or decay in iron is the rust itself.

Under the combined influences of the moisture and carbonic acid of the

atmosphere, iron oxide or iron rust becomes a carrier of oxygen from

the air to the metal, rust begetting rust. It is therefore evident

that this material alone has no preserving effect on iron; in fact, it

promoted its decay.

How is it when combined with linseed oil in the form of paint? In the

economy of nature, iron oxide is a great disinfectant. When in contact

with organic matter and moisture, even at a low temperature, under

favourable conditions, it readily gives up oxygen, destroying more or

less the organic matter, and being itself reduced to a lower oxide.

When thus reduced, with equal readiness it absorbs oxygen from the

atmosphere, and again passes it on, thereby promoting and eventually

ensuring the destruction or transformation of the organic matter with

which it may be in contact, either in the soil or elsewhere. The same

process appears to take place when combined with linseed oil in the

form of paint and exposed to atmospheric influences, the oil being the

organic matter. If linseed oil in drying formed an air-and water-proof

film, it might be urged that the oxide of iron would be entirely

protected from the direct influences of oxygen of the air and moisture.

Such however is not the case.

The most eminent authorities have recently shown that the dried film

of linseed oil, unless united with a pigment that combines chemically

and forms a water-proof coating with it, actually absorbs water very

much like a sponge. Where water will go air will also go, and we thus

have in direct contact with the iron oxide of the paint, which does

not combine chemically with oil, those elements, air, moisture, and

organic matter, which cause the iron to become a carrier of oxygen and

a destroyer of what it is in contact with. It is well known that iron

paint darkens with age; this is caused largely by the iron oxide losing

oxygen, which is partly transferred to the oil, burning it up and

destroying its tenacity, as may be seen by examining iron structures

painted for some time with iron paint or metallic brown, the paint

being found extremely brittle and in feathery scales. This is not

all the damage that is done. The iron oxide in the paint becomes a

carrier of oxygen to the very metal it was designed to protect, and the

process of corrosion is commenced and carried on under the paint, which

eventually peels or scales off, the surface of the metal being found

more or less oxidised and corroded.

Asphalt and iron oxide being thus shown to be entirely incapable of

preserving the iron, it remains for us to consider the effect of red

lead. This pigment has the property of forming with linseed oil a hard

elastic coating, clinging with great tenacity to the metal. It has no

oxidising effect on iron, and does not act as a carrier of oxygen from

the atmosphere after the paint has set, neither does it render the

oil brittle nor promote rust. When red lead fails, it is principally

by gradual wear or friction from the outside. It does not scale or

blister, which both asphalt and iron oxide paints will do, thereby

requiring a thorough scraping and removal of old material before a new

coat can be applied. Any red lead pigment adhering to the metal forms

a permanent base for subsequent paintings, and is utilised in further

preserving the metal. The U.S. Government specifications for ironwork

in the new Library Building of Congress provide that “all the work

not Bower-Barffed must be given one coat of pure red lead paint--not

metallic paint of any kind, but pure red lead--before leaving the shop

and becoming rusted.”

The experiments of the U.S. Navy Department on the preservation and

fouling of plates covered with different pigments may be interesting.

A plate of iron covered with asphalt paint was immersed in sea-water

for eight months and six days at the U.S. Navy Yard, Portsmouth, N.H.

At the end of that period it was found to be covered with scum and mud,

and very badly rusted. A plate coated with iron paint, immersed at

Key West, Fla., was found to be covered with branch shell and coral,

but little paint remaining, and very badly pitted and rusted. A plate

with two coats of red lead, at the Norfolk Navy Yard, was found to

have a few barnacles attached, but to be in fair condition, with no

rust whatever on the iron after the paint was removed. It will be seen

that not only did the red lead protect the iron better than the other

pigments referred to, but that the plates were in far better condition

as regards barnacles and fouling. The superiority of red lead being

thus established, it is adopted for use on hulls of U.S. Government

warships.

On the Dutch State railroads a series of experiments extending over a

period of three years were made with the above pigments on scrubbed

plates, as well as those which had been pickled in acid to remove the

scale. It was found that the red lead was superior in each case to the

others.

If red lead is thus proved to be the best pigment for preserving iron

and steel structures, what is the proper method for applying it? We

have seen above that the value of red lead depends upon its forming

certain combinations with the oil, and actually setting very much the

same as plaster of Paris or cement sets when mixed with water. To

successfully work with the latter substances, it is necessary to put

them in shape as quickly as possible after mixing with water before the

setting takes place. If the chemical action of setting has partly taken

place, the material may be moulded, but it is known that good results

will not be obtained. Red lead, like these substances, must be applied

to the work before it sets with the oil. It is on this point that

failures in the use of pigment have generally occurred, because if it

be applied after the combining or setting process has taken place, the

hard, elastic, clinging coating will not be formed on the iron surface.

The following is the practice of one of the largest shipbuilding

establishments in applying red lead to the hulls of vessels. The plates

are first pickled in a dilute solution of muriatic acid; then passed

between rapidly revolving wire brushes, which remove all scale and

dirt, leaving the iron with a bright, smooth surface; then thoroughly

washed with pure water, and rubbed entirely dry; and immediately

coated with red lead and pure raw linseed oil. The red lead is first

thoroughly mixed with just enough linseed oil to form a very thick,

tough paste, which will keep for several days without hardening. This

paste, as wanted for use, is thinned down to the proper consistency for

spreading with pure linseed oil, and applied at once, care being taken

to leave paint-pots empty at night. A gallon of paint thus prepared

contains about 5 lb. of oil and 18 lb. of red lead, and will cover on

first coat about 500 square feet. In this way the red lead and oil

get their initial set on the surface of the iron, and the closer the

pigment is brought to the iron the more durable will it be found. Some

parties prime iron with iron oxide paint or metallic brown before

applying red lead, which appears to be a mistake, as this paint readily

scales from iron, and, of course, carries the lead with it. Others coat

the iron with oil before applying the red lead. This, too, prevents the

adhering paint from coming in contact directly with the surface, and

should be avoided, provided the iron is properly prepared by thorough

cleaning and removal of any scale and moisture, which is a matter of

the greatest importance.

In priming wood surfaces which are absorbent of oil, the best practice

favours the putting on of a coat of pure oil, or oil thinned with

turpentine, which shall penetrate the surface, and form a binder for

the subsequent coats. With iron, the case is quite different, provided

we have a paint which, from its very nature, can attach itself firmly

to the surface, because it is out of the question for it to hold on

to the surface of iron by any process of absorption into the pores of

the metal, as linseed oil will not penetrate to any extent. Such a

paint should be put directly on the surface of the clean, dry metal,

as is done in the cases of Government vessels referred to, without the

intervention of a coat of oil or other substances.

The rusting of iron before the application of paint, which is sometimes

recommended, should by all means be avoided, as it not only prevents

the contact of the paint with the metal, but induces a chemical action

which may go on with its corroding work under the applied paint.

As to the relative cost of iron oxide paints and red lead, there is no

doubt that the first cost of painting structures with iron oxide is

somewhat less than with red lead. The best railroad authorities state,

however, that labour in painting structural work costs twice as much as

material. The true economy must therefore be sought in the durability

of the paint as well as the preservation of the structure from rust.

Actual experiments have shown that structures painted with iron paint

had to be repainted in the third or fourth year, those with red lead

not until the sixth year.

In the second painting with iron paint, the old material must be

entirely removed before a fresh coat can be properly applied, entailing

considerable increased cost, whereas with the red lead no such expense

is necessary, but, as before stated, a portion of the pigment remains

on the iron, continuing to protect the surface, and is the very best

base for the new coat, besides contributing materially towards it,

lessening the expense of each repainting. It will therefore be easily

seen that, although in first cost red lead may be slightly dearer than

the iron paint, yet in the long run it will be greatly cheaper, besides

giving assurance, for the reasons above stated, that the structure is

not deteriorating from the effects of the atmosphere and paint.

Before closing, it might be well to allude to the effect of lampblack

when mixed in small quantities, say an ounce to the pound of red lead.

It changes the colour to a deep chocolate, a possible advantage in

some cases, and also prevents the red lead from taking its initial set

with linseed oil as quickly as when mixed with oil alone. Experiments

recently made showed that this compound would remain mixed in paste

form with linseed oil some thirty days without hardening. Thorough

mixture is of the greatest importance, and should be done in the dry

state before adding the oil. If rapid drying is desired, Japan dryer

can be mixed with the oil used in thinning the paste before application

with the brush.

Too much stress cannot be laid on the great importance of having the

metallic surface perfectly clean and as free as possible from scale

and rust before the application of the paint. Where pickling with acid

is impracticable, as is frequently the case in railroad and other

structural work, thorough brushing with wire brushes should be resorted

to.

FRESCO PAINTING.--The following observations are due to Prof.

Barff, who dealt with the subject in one of the Cantor Lectures given

at the Society of Arts.

The ground upon which fresco is painted is a lime ground; and in order

to have a permanent picture, it is clear we must have a firm and stable

ground. In order to prepare that ground, first of all the wall must be

absolutely dry; there must be no leakage of moisture from behind. Lime

which has been “run” (as it is technically called by builders) for a

year or a year and a half is best to be employed, for in proportion

as the lime has been carbonated (though it must not be so to too great

an extent) by the action of the carbonic acid of the air it makes a

better and a harder mortar. With this lime must be mixed sand, and a

great deal depends on the selection of the sand. It must be river sand,

and it should be of even grain; the sand should be mixed with water,

and allowed to pass along down a small stream, so that in the centre of

the stream you would have sand grains pretty nearly equal in size. This

is a point of considerable importance. The reason why new lime cannot

and ought not to be used is because it blisters; small blisters appear

on the surface, and that of course would be ruinous to a picture. A

well-plastered wall should not have a blister or crack in it, and this

is secured by having your lime run for some time, of good quality to

start with, and mixed with good sand. There is no chemical process that

takes place in fresco painting other than this, that silicates are

formed by the action of the lime upon the sand, and carbonates by the

action of the carbonic acid of the air upon the lime.

In painting a fresco picture, inasmuch as there is no retouching

the work when it is finished, the artist must make his drawing very

carefully. The cartoon is made upon ordinary paper, then it is fixed

against the wall where the picture is to be painted. The part where

the artist decides to begin his work is uncovered, that is to say, a

portion of the paper is turned down and cut away, but in such a manner

that it may be replaced. Then the plasterer puts fresh plaster, about

an eighth of an inch thick, upon the uncovered portion of the wall, and

the plasterer’s work is of the utmost importance in fresco painting.

The workman ought to practise it well before he attempts to prepare

the ground for a large picture, and it is of the greatest importance

to allow the man to practise for several weeks before he is allowed to

prepare any portion of the ground, even for decorative: painting. In

this way he becomes accustomed to the suction of the wall, and upon

the suction of the wall depends the soundness of the ground and the

success of fresco painting.

When the plaster is first put on, of course it is very soft; the piece

of cartoon is replaced upon it, and the lines of the picture are gone

over with a bone point, so that an indentation is made, and then the

artist begins his painting. At first he finds his colours work greasy;

you cannot get the tint to lie on, it works streaky; but you must not

mind that, you must paint on, but you must only paint on for a certain

time, for if you go on painting too long you will interfere with the

satisfactory suction of the ground, which is so necessary to produce a

good fresco painting. Of course, nothing but practice can tell any one

the period at which he ought to stop. After some practice, you know

perfectly well by the feel when you ought to stop. If you feel your

colour flowing from your brush too readily, you ought to stop at this

period. You must then leave your work for a time, and go back to it

again. And then you will find, as the plaster sucks in the colour which

you have first laid on, that there will be--it may be in the course of

half-an-hour, it may be an hour, that depends upon the temperature of

the atmosphere--a pleasant suction from your brush, the colour going

from it agreeably, and you will find that it will cover better. Now

is the time to paint rapidly, and complete the work you have in hand.

When the colour leaves your brush as though the wall was thirsty for

moisture, you should cease painting; every touch that is applied after

that will turn out grey when it dries, and the colour will not be fast

upon the wall.

You will see, then, how impossible it is, with such materials, to

paint in the same style in which you paint a picture in oil-colour.

Fresco painting involves the adoption of an entirely different style

from oil painting. The frescoes of the old masters are not highly

wrought up, highly-finished works. They depend for their effect upon

the juxtaposition of tints, the shadows being intensified by lines and

cross-hatching. If you look at those reproductions of some of the most

valuable fresco paintings of the old masters, you will see the method

adopted by them depended upon the juxtaposition of tints, not upon

covering over, and over, and over again. That juxtaposition of tints

produces roundness, transparency, and has a very pleasing effect upon

the eye. If two tints are put against one another, they do not appear

to us as if they were single, but each adds something to the effect

of the other, and together they produce a pleasurable and agreeable

effect, if they have been properly selected. We all know how tempting

it is to go back to a piece of painting and do something to it that

ought to have been done before. We think that a touch will improve

it, and we go and make it: but in fresco painting the temptation must

be resisted, for it will be absolutely fatal to the permanency of the

work.

INDEX

African indigo, 47

Alkali for removing old paint, 351

Alumina for lakes, 282

American indigo, 47

---- lamp-black furnace, 20

Aniline black, 25

Animal black, 5, 6

---- matters, nitrogen in, 51

Anthracene oil black, 21

Antimony vermilion, 138

Antwerp blue, 62

Area covered by paint, 359, 360

Arnaudon’s green, 128

Arsenic from cobalt ores, 31

---- orange, 153

---- yellow, 257, 280

Asphalt brown, 101

---- for painting iron, 373

Aureolin, 257

Azurite blue, 40

Balmains luminous paint, 286

Baryta blue, 111

---- green, 109

---- red, 143

---- white, 170

Barytes, 170

Benzoates as dryers, 318

Benzol vehicles, 296

Binder’s cobalt blue, 29

Bistre, 101

Bitumen, 101

Blacks, 5-26

---- adulterations, 6

---- aniline, 25

---- animal, 5, 6

---- anthracene oil, 21

---- bone, 5, 6

---- bone-oil, 12

---- candle, 25

---- “carbon,” 19

---- charcoal, 25

---- coal, 25

---- coal tar, 14, 15, 21

---- coke-oven, 16

---- composition, 5

---- cork, 25

---- creosote oil, 21

---- drop, 11

---- fat, 11, 12, 21

---- Frankfort, 11

---- “gas,” 19

---- gas-tar, 14, 15, 21

---- German, 26

---- impurities, 5

---- iron, 26

---- ivory, 5, 11

---- lamp, 5, 11

---- lead, 26

---- manganese, 26

---- mineral gas, 19

---- ---- matter in, 6

---- natural gas, 19

---- oil, 11, 12, 21

---- oily matter in, 5

---- organic, 5

---- paraffin, 16

---- peach-stone, 11

---- Prussian, 26

---- prussiate, 26

---- resin, 11. 15, 16

---- shale oil, 21

---- Spanish, 26

---- tannin, 26

---- tar, 14, 15, 21

---- testing, 6

---- unimportant, 25

---- vegetable, 5, 11, 25, 26

---- vine twig, 11

---- wine lees, 11

Blanc fixe, 172

Bleaching oils, 332

Blenkinsop and Hartley’s dryer, 335

Blood in priming coat, 352

Blue luminous paint, 291

---- potash, 54, 56

---- salt, 54, 56

---- washing, 90

Blues, 27-100

---- Antwerp, 62

---- azurite, 40

---- baryta, 111

---- Binder’s cobalt, 28

---- Bong’s, 62

---- Bremen, 34

---- Brunswick, 64

---- cæruleum, 27

---- Chinese, 65

---- cobalt, 27, 28

---- cœruleum, 37

---- copper, 34

---- indigo, 42

---- lime, 38

---- manganese, 49

---- mountain, 40

---- Paris, 68

---- Péligot, 41

---- Prussian, 49

---- Saxon, 69

---- smalts, 27, 30

---- soluble, 69

---- Thénard’s cobalt, 28

---- Turnbull’s, 70

---- ultramarine, 70

---- verditer, 41

---- zaffre, 30

Body of pigments, 293

Boiled oils, adulterants of, 331

---- ---- defects, 327

---- ---- substitute for, 352

---- ---- testing for lead in, 328

Boiling oil, 316, 320

Bole, 272

Boletta, 273

Bologna stone, 170

Bone black, 5, 6

---- ---- composition, 10

---- cost of production, 10

---- ---- furnaces, 7

---- ---- qualities, 10

---- brown, 102

---- oil black, 12

Bones, carbonising, 7

---- gases from, utilising, 9

Bong’s manganese blue, 49

---- Prussian blue, 62

Borates as dryers, 318

Braconnot’s green, 123

Bramwell’s prussiate, 58

Brazil-wood lake, 283

Bremen blue, 34

---- green, 112

Brighton green, 112

Brinjes and Goodwin’s paint mill, 346

Brown luminous paint, 291

Browns, 101, 108

---- asphalt, 101

---- bistre, 101

---- bitumen, 101

---- bone, 102

---- cappagh, 102

---- Cassel earth, 102

---- chicory, 102

---- Cologne earth, 102

---- manganese, 103

---- Mars, 103

---- Prussian, 103

---- Rubens, 102

---- sepia, 104

---- ulmin, 105

---- ultramarine, 88

---- umbers, 105

---- Vandyke, 107

Brunquell on prussiate, 59

Brunswick blue, 64

---- green, 113

---- ---- characters, 118

---- ---- dry method, 117

---- ---- testing, 118

---- ---- wet method, 115

Brushes, 355

---- keeping, 355

Buckley’s prussiate works, 59

Cadmium Yellow, 258

Cæruleum, 27

Calcining lamp-black, 23

Calcium hyposulphite, preparing, 139

---- polysulphide, preparing, 139

Candle black, 25

Candle-nut oil, 298

Cappagh brown, 102, 106

“Carbon” black, 19

---- pigments, 5

Carbonising bones, 7

Carminated lake, 283

Carmine lake, 283

Carriages, painting, 361

---- varnishing, 365

Cars, painting, 361

---- re-varnishing, 367

---- washing, 367

Cassel earth, 102

Cassius purple, 143

Cawk, 170

Central American indigo, 47

Cerchione, 273

Chalk, 246

Charcoal black, 25

Charlton white, 172, 254

Chicory brown, 102

China clay, 172

---- ---- artificial, 182

---- ---- characters, 182

---- ---- drying, 175, 181

---- ---- waste products, 179

---- ---- works, 173

Chinese blue, 65

---- green, 118, 129

---- red, 144, 185

---- vermilion, 157

Chromates, iron, 267

---- lead, 260

---- zinc, 268

Chrome greens, 113, 118, 125

---- orange, 144

---- red, 144, 145

---- yellows, 258

Chromes, characters, 266

Clark’s paint mill, 341

Coaches, painting, 361

---- re-varnishing, 367

---- varnishing, 365

---- washing, 367

Coal black, 25

Coal-tar black, 14, 15, 21

Coats of paint, 355

Cobalt benzoate, 318

---- blues, 27, 28

---- borate, 318

---- greens, 119

---- ore furnace, 31

---- oxide blue, 28

---- pink, 144

---- red, 144

Cochineal lake, 284

Cœruleum blue, 37

Coke oven black, 16

Colcothar, 145, 150

Cologne earth, 102

Colour and aggregation of particles, 2

---- ---- chemical composition, 2

---- ---- light, 1

---- causes, 1

---- defined, 1

---- destruction, 2

---- of pigments, testing, 293

---- sense, 1

Condenser, fume, 216

Condensing smoke, 13, 15, 17

Condy’s white lead, 197

Copper blues, 34

---- carbonate, 40

---- greens, 121, 130, 131

---- hydrated oxide, 34, 41

---- nitrate, 36

---- sulphate dryer, 325

Cork black, 25

Cornish umber, 107

Cotton seed oil in linseed oil, 301

Covering power of pigments, 293

Cracking, causes, 363

Creosote oil black, 21

Crucibles for roasting smalts, 32

Cuttle fish brown, 104

Cyanogen in prussiate making, 58

Cyprus earth, 134

Dammar vehicles, 296

Derby red, 145

Derbyshire umber, 106

Discoloration of paint, 356

Douglas green, 120

Drop black, 11

Dryers, 295-338, 365

Dryers, benzoates, 318

---- Blenkinsop and Hartley’s, 335

---- borates, 318

---- chemical action of, 322

---- ---- ---- in oils, 330

---- cobalt benzoate, 318

---- copper sulphate, 325

---- Guynemer’s, 319

---- lead, 325

---- litharge, 316

---- manganese benzoate, 318

---- ---- oxalate, 319

---- ---- oxide, 318

---- ---- sulphate, 325

---- red lead, 316

---- resinates, 318

--- zumatic, 318

Drying china clay, 175, 181

---- paint, 353, 367

---- white lead, 191

Durability of pigments, 294

Dutch vermilion, 167

---- white lead, 185

Dyestuff defined, 1, 3

Egyptian cœruleum, 37

Emerald green, 121

---- ---- characters, 124

---- ---- testing, 124

---- tint greens, 124

Enamel white, 245, 254

Enamelled white, 170, 183

English white, 183, 246

Extraction of oils, 308

Eye, colour effect on, 1

Fascia, 273

Fat-black, 11, 12, 21

Ferric oxide reds, 150

Figuier’s red, 144

Filling before painting, 354, 362

Fineness of pigments, testing, 293

Finishing painting, 363

Firmenich’s vermilion, 165

Fleck’s vermilion, 156

Frankfort black, 11

Freeman’s white, 224, 254

French and Hannay’s white lead, 216

Fresco colours, 257

---- painting, 111, 378

Fume condenser, 216

Furnaces, bone-black, 7

---- cobalt ore, 31

---- galena, 225

---- lamp-black, 12, 14, 16, 17, 18, 19, 20, 21

---- ochre, 277

---- prussiate, 53, 59, 60

---- smalts, 32, 33

Galena, chromates from, 263

---- white lead from, 225

Galloway’s green, 123

Gamboge, 270

Gardner’s white lead, 200

“Gas” black, 19

Gases from bones, utilising, 9

Gas-tar black, 14, 15, 21

Gaud indigo, 45

German black, 26

---- lamp-black, 15

Gmelin’s ultramarine, 81

Green luminous paint, 291

Greens, 109

---- Arnaudon’s, 128

---- baryta, 109

---- Braconnot’s, 123

---- Bremen, 112

---- Brighton, 112

---- Brunswick, 113

---- Chinese, 118, 129

---- chrome, 113, 118, 125

---- cobalt, 119

---- copper, 121, 130, 131

---- Cyprus earth, 134

---- Douglas, 120

---- emerald, 121

---- ---- tint, 124

---- Galloway’s, 123

---- Guignet’s, 125

---- Köchlin’s, 123

---- lokao, 129

---- malachite, 129, 131

---- manganese, 130

---- mineral, 130, 131

---- mitis, 130

---- mountain, 131

---- Paris, 132

---- Prussian, 132

---- Rinmann’s, 132

---- sap, 129, 132

---- Scheele’s, 133

---- Schweinfurth, 134

---- terre verte, 134

---- titanium, 135

---- ultramarine, 73

---- verdigris, 135

---- verditer, 136

---- Verona earth, 134, 136

---- Victoria, 137

---- Vienna, 137

---- zinc, 137

Grey luminous paint, 291

Griffith’s zinc white, 251

Grinding Chinese blue, 67

---- smalts, 34

Ground-nut oil, 297

Guignet’s green, 125

Guimet’s ultramarine, 81

Guynemer’s dryer, 319

Gypsum, 183

Hannay’s white lead, 214

Hartley & Blenkinsop’s dryer, 335

---- on dryers, 322

Hempseed oil, 298

Hind and Lund’s paint mill, 345

Hyposulphite of lime, preparing, 139

Idrian vermilion works, 154

Indian indigo, 43

---- red, 147, 150

Indigo, African, 47

---- American, 47

---- blue, 42

---- carmine, 48

---- Central American, 47

---- cultivation, 43

---- gaud, 45

---- Indian, 43

---- Japanese, 45

---- Javan, 46

---- maceration, 43

---- manufacture, 43

---- Philippine, 47

---- plants, 42

---- preparations, 48

---- qualities, 48

---- testing, 48

Irish umber, 106

Iron black, 26

---- chromates, 267

---- decay, 369

---- oxide for painting, 373

---- ---- reds, 150

---- painting, 369

---- ---- experiments, 375

---- pitching, 369

Italian white lead, 221

Ivory black, 5, 11

Jacquelin’s vermilion, 168

Japanese indigo, 45

Javan indigo, 46

Kaolin, 172, 183

Keeping brushes, 355

Kegs, paint, 349

Kilns, 7, 12, 14, 16, 17, 18, 19, 20, 21, 31, 32, 33, 53, 59, 60, 225, 277

King’s yellow, 271, 280

Kirchoff’s vermilion, 168

Köchlin’s green, 123

Kukui oil, 298

Lakes, 282

---- alumina, 282

---- Brazil-wood, 283

---- carminated, 283

---- carmine, 283

---- cochineal, 284

---- madder, 284

---- yellow, 285

Lamp-black, 5, 11

---- ---- anthracene oil, 21

---- ---- apparatus, 12, 14, 15, 16, 17, 19, 20, 21, 22

---- ---- calcining, 23

---- ---- creosote oil, 21

---- ---- gas tar, 14, 15, 21

---- ---- German, 15

---- ---- in iron painting, 378

---- ---- Martin & Grafton’s, 15

---- ---- natural gas, 19

---- ---- nuisance in making, 23

---- ---- paraffin, 16

---- ---- qualities, 25

---- ---- Russian, 16

---- ---- Shackell & Edwards’ Works, 24

---- ---- shale oil, 21

---- ---- transport, 25

Lapis lazuli, 70

Lead black, 26

---- chromates, 260

---- dryers, 325

---- for white lead making, 186

---- in boiled oil, testing for, 328

---- orange, 147

---- red, 148

---- sulphate, 223

---- whites, 183

Levigating ultramarine, 79

Lewis’s white lead, 223

Light and colour, 1

Lime blue, 38

---- hyposulphite, preparing, 139

---- manganate, 49

---- polysulphide, preparing, 139

---- white, 170, 245

Linseed oil, 299

---- ---- adulterants, 331

---- ---- bleaching, 303

---- ---- impurities, 301

---- ---- purifying, 302

Litharge as a dryer, 316

Lithophone, 245, 247

Lokao, 129

Luminous paints, 286

MacIvor’s ultramarine, 93

---- white lead, 229

Madder, lake, 284

Magnesite, 245

Malachite green, 129, 131

Manganese benzoate, 318

---- black, 26

---- blue, 49

---- borate, 318

---- brown, 103

---- green, 130

---- linoleate, 336

---- oxalate dryer, 319

---- oxide dryer, 318

---- sulphate dryer, 325

Manure from prussiate residue, 57

Mars brown, 103

Martin & Grafton’s lamp-black, 15

Massicot, 148

Measuring painting, 360

Menhaden oil, 303

Metallic paints, 274

Mica, 179

Mills, oil, 309

---- paint, 339, 341, 345, 346

Mineral gas black, 19

---- green, 130, 131

---- matter in blacks, 6

---- orange, 150

Minium, 148

Mitis green, 130

Mixer for paint, 341

Mixing paint, 364

Mountain blue, 40

---- green, 131

Murdoch’s antimony red, 142

Naples yellows, 271

Natural gas black, 19

Nitrogen converted into cyanogen in prussiate making, 58

---- in animal matters, 51

Nuisance from making lamp-black, 23

---- prevention, 24

Ochres, 272

---- characters, 279

---- kilns, 277

---- working, 274

Odour of paint, removing, 356

Oil-black, 11, 12, 21

---- cake, moulding, 313

---- mill, 309

---- seed crushing rolls, 311

---- ---- kettles, 312

---- vehicles, 295

Oils, bleaching, 332

---- boiled, defects, 327

---- ---- substitute for, 352

---- ---- testing for lead in, 328

---- boiling, 316, 320

---- ---- chemistry of, 326

---- candle-nut, 298

---- chemical action of dryers on, 330

---- drying and non-drying, 297

---- extraction, 308

---- ground-nut, 297

---- hemp-seed, 298

---- kukui, 298

---- linseed, 299

---- menhaden, 303

---- pea-nut, 297

---- poppy, 305

---- porgie, 303

---- refining, 335

---- tobacco, 306

---- tung, 308

---- walnut, 307

---- wood, 308

Oily matter in blacks, 5

Old paint, removing, 351

Orange, chrome, 144

---- lead, 147

---- luminous paint, 291

---- mineral, 150

Organic blacks, 5

Orpiment, 280

Orr’s white, 245, 254

Oxide reds, 150

Oxygen in making ultramarine, 78

Packing paint, 349

Paint beds, 274

---- composition, 358

---- covering power, 359, 360

---- cracking, 363

---- defined, 1

---- discoloration, 356

---- drying, 367

---- estimating quantity required, 359, 360

---- machinery, 339

---- mills, 339, 341, 345, 346

---- mixer, 341

---- mixing, 364

---- old, removing, 351

---- packing, 349

---- priming, 354, 362

Painting, 351

---- brushes, 355

---- carriages, 361

---- coats, 355

---- drying, 353

---- filling, 354, 362

---- finishing, 363

---- fresco, 378

---- iron, 369

---- measuring, 360

---- plaster, 378

---- priming coat, 352, 362

---- removing odour, 356

---- surface, 351

---- walls, 378

---- water-colours, 356

---- woodwork, 368

Paraffin black, 16

---- wax vehicles, 296

Paris blue, 68

---- green, 132

--- white, 246

Peach-stone black, 11

Pea-nut oil, 297

Péligot blue, 41

Permanent white, 170, 246

Persian red, 145, 150, 153

Philippine indigo, 47

Phosphorescent paints, 286

Pigments, carbon, 5

---- defined, 1, 3

---- examining, 293

---- requirements, 3

---- testing body, 293

---- ---- colour, 293

---- ---- covering power, 293

---- ---- fineness, 293

Pink, cobalt, 144

Pitching iron, 369

Plaster painting, 378

Pompeian cœruleum, 37

Poppy seed oils, 305

Porgie oil, 303

Potash, blue, 54, 56

---- prussiate, 50

Prevention of nuisance, 24

Priming coat, 352

---- paint, 362

Prussian black, 26

---- blue, 49

---- ---- Bong’s, 62

---- ---- common, 61

---- ---- qualities, 49

---- ---- recipes, 61

---- ---- testing, 50

---- brown, 103

---- green, 132

Prussiate, 50

---- black, 26

---- Bramwell’s works, 58

---- Brunquell on, 59

---- Buckley’s works, 59

---- crystallisation, 55

---- formation, 52

---- furnaces, 53, 59, 60

---- metal, lixiviation, 55

---- of potash, 50

---- pots, 53

---- residue as manure, 57

---- separating: impurities, 56

Pug mill, 341

Purple of Cassius, 143

Putty, 354, 362

Puttying, 354, 362

Realgar, 153, 280

Red lead, 148

---- ---- as a dryer, 316

---- ---- for painting iron, 374

---- luminous paint, 291

---- ultramarine, 77, 80

Reds, 138-169

---- antimony vermilion, 138

---- baryta, 143

---- Cassius purple, 143

---- Chinese, 144, 145

---- chrome, 144, 145

---- ---- orange, 144

---- cobalt, 144

---- ---- pink, 144

---- colcothar, 145, 150

---- Derby, 145

---- Indian, 147, 150

---- iron oxide, 150

---- lead orange, 147

---- minium, 148

---- orange mineral, 150

---- oxides, 150

---- Persian, 145, 150, 153

---- realgar, 153

---- rouge, 150, 153

---- tin, 144

---- Venetian, 150, 153

---- vermilion, 153

Refining oils, 335

Removing old paint, 351

Resin black, 11, 15, 16

Resinates as dryers, 318

Rinmann green, 132

Roller mills for paint, 339, 341, 345, 346

Rosin in linseed oil, 301

Rouge, 150, 153

Rubens brown, 102

Ruby of arsenic, 153

Russian lamp-black, 16

Rutherford & Barclay kiln, 277

Sap green, 129, 132

Satin white, 246

Saxon blue, 69

Schatte’s luminous paint, 290

Scheele’s green, 133

Schweinfurth green, 134

Seed-crushing rolls, 311

---- kettles, 312

---- oils, extracting, 308

Sepia, 104

Shackle and Edwards’ lamp-black works, 24

Shale oil black, 21

Ships’ hulls, painting, 376

Siena earths, 272

Siennas, 272

Silica ultramarine, 74

Smalts, 27, 30

---- crucibles, 32

---- furnace, 32, 33

---- grinding, 34

Smith’s pitching process for iron pipes, 369

Smoke, condensing, 13, 15, 17

Soda for making ultramarine, 78, 92

---- sulphate from ultramarine, 79

---- ultramarine, 74

Soluble blue, 69

Spanish black, 26

---- white, 246

Square blue, 90

Stack white lead, 185

Stampshaw lamp-black furnace, 21

Stangen-spath, 170

Strontia white, 246

Sulphate ultramarine, 72

Surface for painting, 351

Tannin black, 26

Tar black, 14, 15, 21

Terra alba, 183, 246

---- bolare, 273

---- guilla, 273

Terre verte, 134

Thalwitzer’s lamp-black apparatus, 16

Thénard’s cobalt blue, 28

---- white lead, 184

Tin red, 144

Titanium green, 135

Tobacco-seed oil, 306

Transport, lamp-black, 25

---- paint, 349

Tung oil, 308

Turkey umber, 106

Turnbull’s blue, 70

Ulmin, 105

Ultramarine, 70

---- adulterations, 76

---- ancient treatise on, 94

---- artificial, 71

---- brown, 88

---- Brunner on, 82

---- chemistry, 81

---- colouring principle, 75

---- composition, 81

---- direct crucible process, 87

---- Dollfus on, 84

---- effect of silica, 83

---- Endemann on, 82

---- faults, 100

---- German process, 86

---- Gmelin’s, 81

---- Goppelsröder on, 84

---- green, 73

---- Guimet’s, 81

---- Heyne on, 94

---- history, 80

---- Hoffmann on, 83

---- indirect process, 85

---- levigating, 79

---- Leykauf process, 94

---- McIvor’s, 93

---- natural, 70

---- Nejedly on, 94

---- oxygen in making, 78

---- properties, 76

---- red, 77, 80

---- removing soluble salts, 78

---- resisting alum, 75, 77

---- Ritter on, 82

---- Schülzenberger on, 82

---- silica process, 74

---- soda for, 78, 92

---- ---- process, 74

---- ---- sulphate from, 79

---- statistics, 91

---- Stein on, 81

---- sulphate process, 72

---- testing, 99

---- uses, 76, 90, 99, 100

---- varieties, 99

---- violet, 77, 79

---- Wilkins on, 81

Umbers, 105, 272

Vandyke brown, 107

Varnishing coaches, 365, 367

Vegetable blacks, 5, 11, 25, 26

Vehicles, 295-338, 365

Venetian red, 150, 153

Verdegris, 135

Verditer, 136

---- blue, 41

Vermilion, 153

---- antimony, 138

---- Chinese, 157

---- Dutch, 167

---- Firmenich’s, 165

---- Fleck’s, 156

---- Jacquelin’s, 168

---- Kirchoff’s, 168

---- Weshle’s, 168

---- works at Idria, 154

Verona earth, 134, 136

Victoria green, 137

Vienna green, 137

Vine-twig black, 11

Violet luminous paint, 291

---- ultramarine, 77, 79

Wagner’s antimony red, 142

Wall painting, 378

Walnut oil, 307

Washing blue, 90

Water-colour painting, 356

Wax vehicles, 296

Weshle’s vermilion, 168

Wetherill furnace, 225

White lead, 183

---- ---- adulterations, 195

---- ---- characters, 242

---- ---- chemistry of, 187, 192, 193, 200

---- ---- Condy’s, 197

---- ---- cost, 213

---- ---- dangers of, 191

---- ---- dry, 195

---- ---- drying, 191

---- ---- Dutch, 185

---- ---- French & Hannay’s, 216

---- ---- from galena, 225

---- ---- Gardner’s, 200

---- ---- Hannay’s, 214

---- ---- Italian, 221

---- ---- lead for, 186

---- ---- Lewis’s, 223

---- ---- MacIvor’s, 229

---- ---- powdered, 195

---- ---- precipitated, 194

---- ---- stack, 185

---- ---- substitutes, 194

---- ---- testing, 244

---- ---- Thénard’s, 184

---- luminous paint, 286, 290

Whites, 170-256

---- baryta, 170

---- blanc fixe, 172

---- chalk, 246

---- Charlton, 172, 254

---- china clay, 172

---- enamel, 245, 254

---- enamelled, 170, 183

---- English, 183, 246

---- Freeman’s, 224, 254

---- Griffith’s, 251

---- gypsum, 183

---- lead, 183

---- lime, 170, 245

---- lithophone, 245, 247

---- magnesite, 245

---- mineral, 183, 245

---- Orr’s, 245, 254

---- Paris, 246

---- permanent, 170, 246

---- satin, 246

---- Spanish, 246

---- strontia, 246

---- terra alba, 183, 246

---- whiting, 246

---- zinc, 247

Whiting, 246

Wilson’s fume condenser, 216

Wine-lees black, 11

Wood charcoal black, 25

-- oil, 308

Woodwork, painting, 368

Working ochre beds, 274

Wright’s paint machinery, 339

Yellow luminous paint, 291

---- prussiate, 50

Yellows, 257-281

---- arsenic, 257, 280

---- aureolin, 257

---- hole, 272

---- cadmium, 258

---- chrome, 258

---- gamboge, 270

---- King’s, 271, 280

---- lakes, 285

---- Naples, 271

---- ochres, 272

---- orpiment, 280

---- realgar, 280

---- umbers, 272

Zaffre, 30

Zinc chromates, 268

---- green, 137

---- oxide, 37, 247

---- sulphide, 250

---- whites, 247

---- ---- characters, 255

Zumatic dryer, 318

LONDON: PRINTED BY WILLIAM CLOWES AND SONS, LIMITED, STAMFORD STREET

AND CHARING CROSS.

End of Project Gutenberg's Pigments, Paint and Painting, by George Terry

Pigments, Paint and Painting: A practical book for practical men · 第 16 / 16 章