Below is an excerpt from William Cooper' Glazier's Manual, 1835.
The invention of the art of colouring glass— that is, imbuing it throughout with any particular tint— seems to be nearly equal
with the discovery of the art of making the substance itself. Egyptian ornaments, and Druidical beads, of the highest antiquity,
as already noticed in the historical department of this work, are found, of many and surpassingly beautiful colours; but the
art of staining and painting glass, so as to form pictorial representations of objects, is of comparatively recent date,
although the precise period of its introduction is unknown. It is certain, however, that it has existed for many centuries,
but in different stages of excellence, and, like every other art, has been gradually advancing in improvement. A pretty general,
but very erroneous, idea exists, with regard to the superiority of the colours employed in ancient glass painting over those in use
at the present day. It is relieved by many, and taken for granted by others, :hat not only is the brilliancy of the former unattainable
by modern skill, but that the art of producing them is itself entirely lost. This is a very mistaken notion, for not only are the
colours now employed as brilliant and durable as those of the ancients, but others have been added, which they most probably did
not know how to produce, or at least did not use. Amongst these are pink, straw colour, and other compound tints. That indiscriminating
veneration for every thing ancient, which has so often, so unjustly, and so seriously interfered with the claims of modern merit
to the encouragement to which it is justly entitled, has operated against glass painting and staining with perhaps fully more force
than against any other art. It has induced a belief, that excellence in the art is confined to the ancients — that nothing can be now
done to equal their triumphs in it—and that all the productions of the modern glass stainer and painter are mere flimsy imitations of
those of the artists of the fourteenth and fifteenth centuries. Than this there never was any notion more unjust or more absurd;
and the writer feels assured, that nothing farther is necessary to convince any one of that injustice and absurdity, than a visit
to the warehouse or workshop of any respectable glass painter and stainer of the present day.
But glass painting and staining labours under other, and perhaps greater, disadvantages than that of being reckoned a decayed art.
Some of these are inherent in itself, others are contingent^ and others are the result of prejudice, or spring- from a deficiency of
due encouragement. Not the least of these disadvantages is the circumstance of its being' considered a luxury of too presumptuous a
character, and of too expensive a nature, to be employee/ in the embellishment of the houses of persons of moderate income. This is the
result of impressions derived from the uses to which painted and stained glass was of old exclusively applied,—the adornment of stupendous
cathedrals, magnificent palaces, and baronial mansions — a circumstance which has had the effect of associating it with ideas of
gorgeous splendour and vast expense —ideas which are yet in full operation, although the exciting cause has long since disappeared.
Most people, as already remarked, are under an impression that painted or stained glass is much too expensive, and too fine a thing
for them to think of indulging in as an article of luxury, and they are at no pains to correct the
error, either by reflection or inquiry. Were they to make proper investigation, they would find that modern improvement has brought
this elegant ornament within the reach of very moderate circumstances.|
It may be remarked, too, as something singular, that while almost every other art has been called on to contribute in some way or
other to our domestic comforts, or to the adornment of our dwellings, that of glass painting and staining, though its productions
are not more expensive than some of these, and are certainly not inferior in elegance to many of them, should yet be but rarely
applied to domestic purposes, where it could be employed with such delightful effect. When stained glass has been used in the
embellishment of the mansions of the middling, or even of the upper classes, it has been hitherto in a great measure confined
to hall and staircase windows, and to windows placed in similar situations, but its use might be much extended, with great advantage
in point of ornamental effect.
If the windows, for instance, of a drawing-room, were filled with stained glass, whose prevailing tints should harmonize with the
predominating colour in the apartment, an effect would be produced at once novel, striking, and singularly pleasing-.* Where the expense, or any other objection, might be urged against figured glass, in which
masses of brilliant colour are employed, that description which is plain, and of one tint,—such as brown, ruby, pale yellow, etc. —
might be substituted; and, if selected with reference to the prevailing colour of the interior, with the view of either heightening
or deepening1 its complexion, a delightful warmth and richness of tint would be thrown around the apartment, such as no other
contrivance of art can communicate. And where both of these descriptions of coloured glass might be found unsuitable — a circumstance
for which, it is apprehended, there could be only two reasons, namely, the expense, or the too great exclusion of light—there is still
a third description of ornamental glass, which might be employed, and which is free from both of these objections. This is a pale
tracery, resembling lacework, which, when
properly executed, is exceedingly beautiful, and imparts to a room an appearance of singular lightness and elegance.
It would not, perhaps, be altogether accurate to say, that a want of taste is the cause of the neglect with which glass painting
has been treated, and of the very little demand that there is for it; neither do we think that it does entirely proceed from this
cause. It is one of those things of which it would be, probably, more correct to say, that it has rather been overlooked than
neglected, and that, therefore, little more is wanting than to call the public attention to it, to procure for it a share of
that popularity and encouragement, which some more fortunate, but certainly not more deserving arts enjoy.
Except in the name, painting on glass has no resemblance to any other department of the pictorial art but that of porcelain.
Both the colours, and the process of their application throughout, are entirely different. While animal and vegetable substances
are freely used as colouring matter in every other department of the art, they are wholly excluded in that of glass painting,
where all the pigments used are subjected, after being laid on, to the operation of fire, to make them penetrate the glass, or
become fused on its surface — a process which would destroy the colouring propensity of organic substances.
Most colours employed in glass painting are oxides of minerals such as gold, which
not only stand the fire, but require the powerful interference of that agent to bring on their brilliancy and transparency.
Some colours, with the application of heat, penetrate the body of the glass, and, from this circumstance, are called stains:
while others, when mixed with a vitreous substance called flux, become fused or vitrified on the surface. The former produces
a variety of colours, and all of them are perfectly transparent. The product is only semi-transparent, but
they may be made to yield any colour or tint required.
In preparing these colours, the most important point to be attended to is, to have all those that are to be used at the same
time of an equal degree of softness. To attain this, those that are hard, and require a great degree of heat to make them
effective, must be fixed first; leaving the soft colours, for which a slight heat only is necessary, to the last. If used
promiscuously, and without regard to this precaution, some of the colours would be rendered too fluid, while others would be
insufficiently fused, and the work in consequence spoiled.
It is likewise of great importance to make a proper selection of glass for the purposes of staining and painting,
as one kind will assimilate more freely with one colour than with another. The description of glass generally chosen for
painting or staining is the best crown glass.
It is not thought advisable to enter at greater length here into the details of the process of glass painting and staining;
because, in the first place, this work is intended, by the author, for the use of the glass-cutter and glazier chiefly, to
whom such information is unnecessary, and which, therefore, were it introduced here, would swell the volume to too great a
size. In the next place, all such details would be nearly useless for any practical purpose, there being scarcely a possibility
of either communicating or acquiring such a knowledge of the art of glass painting or staining as would enable any person to
practise it successfully. Nothing but personal observation and long experience can do so. And thus it is, that all the printed
directions and instructions for the prosecution of the art, of
which there is no lack, are found to be almost wholly useless when attempts are made to act upon them. In short, to those who
have no knowledge of the art, no written instructions could be of any avail; and to those who have, the writer has nothing new
regarding it to communicate.