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WE come now to notice those curious and instructive | Gold is employed for purple; a mixture of gold and processes of the glass-stainer whereby the chief material is produced in

silver gives a rose colour; iron, a brick red; iron, copper, and manganese, in various proportions, form browns and blacks. Perfectly black glass, in large slabs, is now imported from Russia, and is used instead of black marble in ornamental furniture.

Blue is obtained from cobalt, commonly called zaffres. The origin of this term is curious: the old glass-stainers preserved their processes with jealous secresy; and when urged to disclose them frequently gave false recipes †, one of which for a blue stain was sapphires. When oxide of cobalt became known as the real material, this was supposed to be the

Storied windows, richly dight, Casting a dim religious light. When certain metallic substances are made, through the agency of heat, to combine with colourless glass, the result is a stain which penetrates more or less deeply into the very substance of the glass itself. As the choice and management of these metallic colouring matters are points of the greatest importance, we will first offer a few details on the subject. We have already described the general processes of glass-blowing, so that by referring the reader to that article, he will the better appreciate the following for enamel colours and stains contained in many of our works on + The same practice is still adopted, and the "valuable recipes" details. the subject, are almost worthless. M. Brongniart well observes, The colouring materials are in all cases metallic." It is very remarkable that if the processes described in these works were strictly followed, it would never be possible to form the colours for which those recipes are given." 426

* See Saturday Magazine, Vol. III., p. 131.

VOL. XIV.

sapphires of the old stainers; and by an easy corruption, it was called zaffres, under which name it is now commonly known in commerce.

Pure silver possesses the extraordinary property of staining glass yellow when brought in contact with it at a dull red heat, and this is the material employed for yellow, orange, or red stains; any one being produced by modifications of the same process. No flux is used; but the silver is ground with ochre or clay, and laid in a thick stratum on the glass. After the process of firing, although the silver is not found to adhere at all to the glass, yet a transparent yellow stain is imparted to it. If a large proportion of ochre be used, the stain is yellow: if the proportion be small, it is orange; and by repeated firings the latter is, in some unaccountable way, converted into ruby red; and this is the process we before alluded to for procuring this colour, although it is not equal to that of the old artists.

since a slight excess of heat produces a dull blue, or a dingy brown, instead of a red. A similar remark applies when copper is the material. When taken out of the melting-pot, it often exhibits only a faint greenish tinge: it is then worked into panes, by the exposure of which to a gentle heat a brilliant red is produced: this is an extraordinary and unaccountable fact.

That copper will produce a red stain was discovered (perhaps we may say re-discovered) in a remarkable manner. The reader is probably aware that PlateGlass is formed by rolling out the refined glass, in a molten state, upon a steel table. The transfer of the glass is sometimes made by tilting the melting-pot over the table, and at other times by lading it out by means of a copper ladle, which must occasionally be dipped into cold water, to prevent it from being warped, or perhaps melted, by the heat. Many years ago, at the plate-glass works of St. Gobain, the latter mode of manufacture was adopted; and on one occasion, the cold-water precaution being neglected, the ladle remained in the melting pot. The workman foolishly thought that he should find his ladle at the bottom of the melting pot: the casting was proceeded with, and all the contents of the pot exhausted, but the ladle had disappeared. No further notice was taken of the circumstance, till the glass having been annealed and being about to be polished, the workmen, to their surprise, discovered traces of the lost ladle in metallic particles of copper embedded in the glass, together with large streaks of a fine red colour. This circumstance becoming known, a variety of exsub-periments were tried by different chemists and glassstainers, with various degrees of success.

In enamel painting, copper yields a fine green, but it does not answer well on glass; and no other material being known to afford a good green, an ingenious contrivance is adopted. Since a mixture of yellow and blue produces green, the glass, which in other cases is stained on one side only, is in this case stained blue on one side, and then, by a second process, yellow or lemon colour on the other.

In addition to the above modes of staining glass, another mode is resorted to, when practicable. It consists in melting common glass, or its ingredients, mixed with the colouring matter, in a melting pot, in the same way that ordinary glass is made. Here the resulting panes are coloured throughout their stance, and such glass is called pot metal.

Another mode consists in flashing; that is, uniting a thin layer of coloured glass with another layer which is colourless. The coloured layer is sometimes included between two layers of colourless glass. Such glass is prepared thus: the glass-blower has two melting-pots in the furnace, one containing colourless and the other coloured glass, each in a melted state. He dips his rod first into the colourless glass, and then into the coloured, a portion of which adheres to the lump first taken up. If it is desired to enclose the coloured film between two colourless layers, he again dips his rod into the colourless glass. He then proceeds with the processes of blowing and whirling, as in the manufacture of the ordinary crown glass for windows. We have seen some specimens of fine ruby-glass made in France by this method, which is also employed in the formation of perfume-bottles, and other ornamental vessels of particular colours.

The production of the ruby red stain has long been a most interesting feature connected with the details of our subject, We will therefore conclude this short article with a few anecdotal remarks

thereon.

Gold, copper, and silver, are the reputed sources of the splendid reds of the old stainers; and so general at one time was the notion, in France, that gold was the colouring material, that in 1793, the French government actually collected a large quantity of fine old red glass, and demolished it for the purpose of getting the gold which, as it was supposed, afforded the colouring material. It is needless to remark that they were not very successful, although it was stated, by Kunckel, that gold melted with flint glass afforded a fine ruby colour; but as Kunckel was a stainer by profession, and dérived much profit from his ruby glass, which was really fine, there is no wonder that he did not publish his process.

When gold is employed, great care and experimental knowledge is necessary, especially as to temperature;

Such then is a brief account of the colours employed in the production of stained glass. We come now to notice the method of applying them when certain patterns or figures are required, as in the case of a church window; but for the sake of greater simplicity we will show the mode of producing a small ornament, such as a rosette, on a pane of colourless glass.

A pattern or drawing of the desired figure is prepared, the outlines of which are dark and well defined. This is attached to the glass by means of wafers at the corners; the glass serving the same object as the glass of a picture-frame, the design being perfectly visible through it.

The colouring materials are ground up with flint glass, lead, and borax, the ingredients of a very fusible glass, which acts as a flux. Fluidity is given to the colouring matter and flux, by mixing them with a volatile oil, such as turpentine: amber oil, capivi balsam, or gum water, are also employed.

The pane of glass, with its pattern attached, is mounted upon an easel, and the figure is painted on the glass with the above colours, by means of long haired sable pencils. A rest stick is also employed, and the general process resembles that employed in painting on canvass.

When the same figure is to be produced upon a number of similar panes of glass, the pattern need not be shifted from the first pane; but the second piece of glass being laid upon the first, the process is repeated as before.

The

For the production of more elaborate figures, such as the full-length portrait of a man, including a portion of the building in which he is placed, two methods are united to attain the desired result. face and other parts are painted on a piece of glass of the desired form; but the drapery &c. are cut out from pieces of glass, to which various but equable stains have been previously imparted. These irregu

by Rubens, for the high altar of the Recollet Church, at Antwerp; and the other, from which the groups at the sides were taken, was the composition of Lambert Lombard. A fine altar-piece, of Norway oak, is placed under the sombre but pleasing light of this rich window.

The frontispiece which illustrates the present article, is a copy of an old window in York Cathedral, the work probably of John Thornton, the terms of whose engagement we stated in our former article, p. 18. (From a Correspondent.)

lar pieces are built up into a picture, the joints being | from two different designs; one of which was painted made with glaziers' lead, care being taken to throw such joints into the shaded parts of the picture. The sheets of coloured glass are prepared by a process similar to the blowing and whirling as adopted by the ordinary glass-blower, in the production of common window-glass: but for certain stains, and for all designs which have been painted on panes of glass, a method of fixing the colours, by burning, is adopted. The process of burning need not be described very minutely. A slight notice thereof will be sufficient for the general reader. The panes of glass are taken separately, and placed in a box of iron-plate, called a muffle. This muffle is furnished with shelves of ironplate, covered with powdered lime, to prevent the glass coming in contact with the hot metal surface. The muffle is now placed within a furnace, and the contents are gradually brought to a dull red heat, by means of fuel that does not produce flame; for which purpose coke and charcoal are usually employed. The heat produced must be exactly sufficient to fuse the flux, by which means the colouring material becomes firmly united to one surface (the upper one) of the panes of glass. Hollow tubes pass out from the furnace into the air, through which the process of burning in the colours can be witnessed; and it requires the watchful eye of experience to detect the precise moment when the process is complete. The fire is then damped and allowed to go out gradually; and in ten or twelve hours (the glass slowly cooling and annealing all the while), the burning process is completed.

When the glass is removed from the muffle, the colours are scraped or brushed off separately; some of the more valuable stains being reserved for repeated use, since a small fraction only of the colouring matter is absorbed by the glass.

The panes are thoroughly cleaned and separately examined. If any flaws or faults appear, the colour is again applied, and a second burning is adopted. This second burning also tends to remove spots or stains, and serves to heighten the colours.

Such then is a brief account of the processes still adopted, and which were probably adopted by the older artists in the production of stained glass. Many of the fine windows which were painted previous to the Reformation, were demolished during that eventful period. In some cases the windows were pulled down, and the glass concealed in the vaults of the holy building; and thus was it preserved from demolition. In more peaceful times the windows were restored: but it has frequently happened that the concealed glass has been forgotten; sometimes it was stolen or broken by those who were ignorant of its value. As an example of the treatment bestowed on ecclesiastic ornaments, during the time of Cromwell, we may instance the fine window over the altarpiece, in the chapel of St. Peter's College, Cambridge. This beautiful chapel was built by subscription in 1632. Some of the embellishments with which it was decorated on its first erection were demolished or removed during the civil wars. "In 1643," say the Parliamentary Commissioners, we went to Peterhouse, and pulled down two mighty angels, and divers other angels, the four evangelists, and Peter with his keys, on the chapel door; together with about one hundred cherubim, and many superstitious letters in gold." The beautiful painted glass, which now adorns the east window, was happily rescued from the profane nands which at that time waged war against the arts by being taken to pieces and concealed in boxes. It represents the history of our Saviour's crucifixion between the two thieves. It is said to have been copied

66

[In our first article on Stained Glass Windows, (page 18 of the present volume,) we gave a list of English glassstainers, with a slight notice of their principal works. It appears that in this list we omitted the names of several stainers who are still exercising their profession; names for the artists, scarcely known." We are anxious to do which, as our correspondent remarks, are, "unfortunately justice to all; and while we cannot but regret the omissions complained of, it will be seen how difficult it is to avoid omissions of the names of artists whose ingenious and beautiful productions are, we regret to state, so seldom brought before the public at large.]

Muss, a skilful painter, who died in 1824. Among his principal works were the Assumption of the Virgin, after Murillo, (for Sir Thomas Baring;) the Battle of Neville's Cross at Brandspeth Castle; several windows at Eaton Hall, the seat of the Marquis of Westminster, and many others. MILLER, a painter of the present day, whose chief works are done in imitation of the ancient style.

HOADLEY and OLDFIELD, two successful artists now living. Their works are remarkable for their minuteness, high finish, and elaborate detail. Many of their performfavourable notice. Among their works may be mentioned ances were lately exhibited to the public, and met with the copies of those well-known engravings of Martin, viz., Belshazzar's Feast, Joshua, and Nineveh; the noted Kemble family of Harlow; Faith, Hope, and Charity, after Reynolds (a copy of these were done for Charles the Tenth of France). These artists are now engaged upon a splendid window for the Rev. Gale Townley, after Spagnoletti, of the Descent from the Cross, &c., which, it is to be hoped, will be shortly exhibited to the public, and thus prove to the world that the art of painting on glass is not lost, as many foolishly imagine.

WILMSHURST, the painter of the well known window of the Field of Cloth of Gold, a magnificent production, which was for some time exhibited in Oxford-Street, and unfor tunately fell a sacrifice to fire.

NIXON, the painter of many beautiful figures, &c.

EVANS, whose principal works were a window at Hornsey Church, and another at Winchester,

A PIOUS acquaintance, remarkable for the quaint shrewdness of his observations, one day, when walking in a garden, having pulled a flower of exquisite loveliness, after expressing, in his own characteristic way, his admiration of its various beauties, took up a clod of the soil in his other hand, and naïvely, but emphatically, exclaimed, "What but Almighty power could extract that from this?" If there was anything ludicrous in the manner, there was nothing but truth and sublimity in the sentiment. Everything in the operations of the Creator is worthy of devout admiration, but I scarcely know anything in the inanimate world which brings together and concentrates so many wonders of designing wisdom and benevolence, as the structure and qualities of a flower,-and assuredly not a little is added to the surprise and pious feeling with which this delightful production is contemplated, when we think of the crude materials from which it is elaborated. The beauty of form and colour, the sweetness of the fragrance, the delicate and skilful nature of the organization, the careful provisions, the forethought, the contrivance, the suiting of parts, as regards the propagation of the species, the adaptations to the subsistence and enjoyment of the insect tribes,—all produced by the artificial union of a few simple and apparently unfit substances, cannot fail to excite in the reflecting mind, the most lively sentiments of astonishment, and to force upon it the conviction, that here, without doubt, is the finger of God.-Duncan.

ELECTRICITY.
No. VIII.

THE LEYDEN Jar.

WHENEVER the electrical equilibrium of bodies is disturbed, both kinds (or states) of electricity, are invariably brought into action. And this happens, not only, as we have on a former occasion mentioned, at different parts, or at opposite sides, of any particular substance in which a redundancy of electricity may be excited or accumulated; but its influence extends to other substances in that vicinity; although the latter be at too great a distance for any actual transference to take place. This is termed electrical induction; of which we shall give a brief explana

tion:

3.

thus arranged, and a imbued with positive electricity, b will instantly become negative, c positive, d negative, e positive, and so on throughout the whole series. This will be shown by the feathers in each case attracting each other; a result plainly indicating, that they are in opposite states of electrical excitation.

We remark further, that these experiments will be still more interesting, if to different parts of a series of insulated conductors, we attach pith-balls in pairs; by which we shall ascertain that induced electricity, is more active at opposite sides of spherical, and opposite ends of elongated conductors, than at any other parts, and that its intensity gradually diminishes towards the centre of such bodies, becoming there entirely neutral.

The effects of electricity, thus operating at a To begin with one of the most simple illustrations distance from the excited body, are not in any degree we can select, let the figures in the margin represent diminished by interposing a third body; provided discs of tin-foil, similiar to those on the spiral tube, however, that the latter be not liable to have its own of which a description was lately electrical relations disturbed. A plate of glass, thereN P N P NP given. It will, of course, before, may be placed between two bodies acting on each understood, that if these discs other inductively, without producing any perceptible 1. 2. were in contact, and electricity change in either. communicated to any one of them, it would diffuse As induced electricity acts independently of interitself over the whole, in the same manner as if they posed bodies, its intensity, supposing all other circumconsisted of an entire piece of metal. But the discs stances equal, being determined by the relative sizes are not in contact; and consequently, the electricity and distances of the exciting and the excited bodies; can pass from one to the other, only by penetrating so must it be remembered, that its effects cease by the the interposed column of air; which is, indeed, the removal of the latter. Hence, therefore, supposing intention of their being so arranged. If, however, we the spherical body a in the preceding figure, to contain examine this matter a little more attentively, we shall a certain quantity of electricity, which operates inducfind that the electrical relations previously existing tively upon the insulated conductors, so long as they among these pieces of tin-foil, are affected by mere remain within a certain distance of a and of each other; proximity to an electrified body. For example;-on removing them, the conductors are immediately Let us suppose the disc marked 1, to represent that restored to their former state of neutrality, the sphere at the end of the spiral tube already referred to, and still retaining the same quantity of electricity that it which first receives the spark from the machine. The did before the experiment commenced. Thus it will tube being brought near the conductor, before a appear, that induced electricity, implies that no actual spark can pass from the latter to the former, the whole interchange, or transference takes place between the of the discs, whatever be the number of the series, 'bodies subjected to its influence. Nothing is gained will be electrified by induction; which means, that the by one, or lost by the other; the only effect being the electricity, excited and brought into action by the temporary disturbance, accompanied by a different machine, and accumulated in the conductor, exercises arrangement, of the electricity existing in bodies, an influence on surrounding objects, although no part when in their ordinary and unexcited state. We could of the redundant electricity is transferred to any of enumerate many other examples, tending to the conthose objects. Supposing the conductor to be firmation of these views; but enough, we think, has charged with positive electricity, the disc at the ex- been said, to prepare the way for understanding the tremity of the tube, and all that succeed it, will be principle and the method of using the Leyden Jar; electrically excited in the following manner, namely, which has been the chief design of our somewhat that part of the first disc, nearest to the conductor, lengthened remarks on electrical induction. will exhibit negative, and the part most distant positive, electricity. This is indicated by the letters N P, and is equally applicable to the series, as to any one particular disc. The instant a spark passes from the conductor to the discs, the induced electricity is dissipated; but is again renewed in the interval between the passing of each spark, although that interval be too brief either to be observed or computed.

To render this class of phenomena more intelligible, let a in the following figure, represent a body positively electrified, near to which are to be placed any convenient number of insulated conductors, with feathers attached to them as at b c and d, and the last, as at e communicating with the earth. The apparatus being See Saturday Magasine, Vol. XIV., p. 24.

In the instances of induced electricity just mentioned, it will be observed, that the exciting, as well as the excited bodies are conductors, and the medium through which the excitation is communicated, is an imperfect conductor; the latter consisting of the air interposed between the two former. Now although this, or any other particular arrangement, is not indispensable to the existence of the phenomena, yet it is necessary in every case that a non-conducting, or at any rate, an imperfectly-conducting substance should be present.

To illustrate this by experiment, let us take a pane of window glass, clean and dry, and if one side of it be rubbed briskly with a warm and dry silk handkerchief, both sides will become electrically excited. This may be ascertained by presenting to the side which has not been rubbed, a small pith-ball, suspended by a silk thread, when it will be attracted by the glass; and then if it be immediately presented to the side which has been rubbed, the same ball will be repelled; a proof, not only that

a

electricity is diffused over both sides of the glass, but also that the electricity on one side is positive and on the other negative.

The same results, but with greatly-increased action, will follow, if one side of the glass be held near the conductor of an electrical machine, taking care, however, whilst this is done, to pass the finger gently backwards and forwards over the other side, otherwise the glass will receive only a very feeble charge. In this case sparks will pass from one side to the other of the glass, which will have the appearance of penetrating it; they are occasioned by the sudden discharge of the accumulated electricity over the edges of, not through, the glass.

In both these experiments we have examples of electrical induction, which takes place through the substance of the glass; in the first, the side rubbed with silk is charged with positive, and the other, of course, with negative electricity; and, in the second, supposing the positive conductor to have been employed, the arrangement will be the same.

Now let us advance a step further.

Glass, it is well known, is a non-conductor, and hence it is difficult to diffuse electricity equally over every part of its surface; and, supposing that to be done, we find it just as difficult to disengage the electricity from the glass again, that is, in such a way as to serve any useful purpose. But these objects are fully attained by covering the glass on both sides with tin-foil, which must not, however, reach to within about two inches of the edges, as represented in the accompanying figure.

A pane of glass thus coated and charged with electricity, by placing one side of it near the conductor, in the manner just now directed, if we make the tin-foil on its opposite sides to communicate with each other, a sharp report is heard, accompanied by a bright spark, indicating that the accumulated electricity has been dissipated, and both sides of the glass restored to their former state of equilibrium.

Let it be particularly noticed, that the use of the tin-foil is to enable us to diffuse electricity uniformly over the surface of the glass, and having done so, to recover the whole of it again whenever we please, giving it any required direction in a condensed, or rather an accumulated form. The thin coating of metal in contact with the glass, performs only the office of a conductor; for it is possible to remove it without dissipating any of the electricity, which adheres to the glass, not to the metal.

But although a pane of glass may do for an illustrative experiment, it is difficult to manage, very liable to be broken, and capable of receiving and retaining only a feeble charge, and, therefore, not adapted for general use.

Here is a figure of the Leyden Jar, the most convenient form in which we can employ coated glass. It consists of a vessel, similar to those used as show-glasses by confectioners, coated on both sides, to within about four inches of the top, with tin-foil. The jar, as here drawn, has a cover of mahogany, or other hard wood, through the centre of which passes a brass rod, terminating above by a ball of the same metal, and below by a chain

reaching to the bottom of the jar.

Leyden ars, fitted up as just described, are very portable, but are not the most useful; we prefer them without any cover. In our next paper we shall give instructions for constructing them on our own plan, as we shall also for performing, by their aid, some very beautiful experiments.

THE ECONOMY OF BEE-KEEPING.

NOTHING gives me greater pleasure in a country walk than to hear a bee buzzing by my ear, as I pass a cottage fence. A row of bees is a sign the owner takes pleasure in his home. And a word of advice to such a man is likely to come to good.

In the first place, Never kill your Bees. In France,

Germany, and Switzerland, they never kill their bees. In some places they make straw hives, with the top to take off, and fasten it down with wooden pegs in July they pull out the pegs, and with a large knife cut away the top of the hive from the comb, and cut out what honey the bees can spare, never caring for those flying about their heads; for they will not touch them if they have a pipe in their mouth. And when they have helped themselves they peg the top down again; and the bees will gather enough in August and September for the winter.

Others put a large hive on the top of a strong stock, in May, which prevents their swarming; and this hive they take off when full. Others turn up their hives in July and Others put wooden August, and cut out some combs. boxes on one another, putting empty boxes below, and taking away full ones from the top.

I saw a doctor in Switzerland take honey from twelve hives: he got fifteen pounds from each. The better way is such as is now practising by the Bee Society at Oxford.

You may find funguses, called puff-balls; when ripe they give out a powder like smoke; pick them when half ripe, (the largest are the best,) and dry them; the fungus is fit for use when it will hold fire like tinder. Keep them till you take your bees.

In autumn weigh your hives-mark those which are the heaviest and lightest; this you cannot rightly do unless you weigh them before you put your swarms in, and mark the weight outside. Casts, except they are very early and strong, will scarcely stand the winter.

When the honey season is over, stop up over night those you mean to take up. In the morning take a piece of the fungus, twice as big as a hen's egg; put it in a stick, split at one end and sharp at the other have a hive as large as that you mean to take up, fixed bottom upwards, (a pail will hold it well). Then light your fungus, and fix the sharp end in the hive you have turned topsy-turvy, and wet cloth round the two hives, that no smoke may get out. place the hive you intend to take on the top of it, and tie a You will soon hear the bees drop down and tap the top of the full hive to make the bees fall quicker. When they are all quiet, lift the full hive off, and turn all the bees that have fallen on a table, and they will get well again in twenty minutes. Look for the Queen Bee, keep her safe, and sweep all the other bees back into the empty hive; then cut the combs out carefully, and if you have not already found the Queen, it is likely that you will find her at the top of the hive.

Sweep the bees with a feather back into the hive out of which you have taken the combs.

As soon as the bees begin to crawl about, take a hive which is strong enough to stand the winter, or though heavy, weak in bees; stop it up the night before, and put it gently on the empty hive where the smoked one stood before, keeping the bees asunder with coarse canvass, or a sheet of thick paper with pin holes; a sheet of tin, punched with holes, the sixteenth of an inch over, is best of all. Keep the bees for twenty-four hours apart.

On the evening of the second day, draw away the tin, empty hive, and the bees which have forgotten their queen paper, or canvass, without disturbing the hives, tap the which you have taken away, will go up into the full hive, as if they belonged to one swarm.

Early the next morning, when all is quiet, set the doubled hive back in its old place; if you pull away the tin too soon the bees will fight terribly and kill many, and perhaps their queen; for fear of this you must take care of the queen you smoked.

The next day, after the stock has been put back to its own place, put this queen to the mouth of your double hive, and

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