Chapter C: D E F are the four printing cylinders, named in the order of their (30)

2 Primes of Cyanic or fulminic Acid = 34 × 2 = 68 24
1 Deutoxide of Mercury = 216 76
--- ---
284 100

As these 284 parts of fulminate contain 200 of quicksilver, so 142 parts of fulminate will contain 100 of quicksilver. Whence it appears, that when only 130 parts of fulminate can be obtained in practice from 100 of quicksilver, 8-1/2 parts of quicksilver out of the 100 are unproductive, that is, are expended in the etherized gas, or left in the residuary acidulous liquid. By the above experimental and theoretical analysis, 91·5 parts of quicksilver enter into the composition of 130 parts of true crystalline fulminate. The complete accordance here exhibited between theory and practice removes every shadow of doubt as to the accuracy of the statements. 100 parts of fulminate consist of--

Mercury } 70·4 } Peroxide 76·0
Oxygen } 5·6 }
Fulminic acid 24
-----
100·0

_Question 3._ May the gas or vapour produced by the inflammation of the fulminate of mercury, when combined with a portion of gunpowder, be considered in its nature corrosive of iron or brass?

_Answer._ I have suggested to Mr. Lovell, of Waltham Abbey works, that the fulminate may be probably diluted most advantageously with spirit varnish made of a proper consistence by dissolving sandarach in alcohol. When well mixed with this varnish, a small drop of the mixture will suffice for priming each copper cap or disc; and as the spirit evaporates immediately, the fulminate will be fixed to the copper beyond the risk of shaking or washing away. On the Continent, tincture of benjamin is used for the same purpose; but as that balsamic resin leaves in combustion a voluminous coal, which sandarach does not, the latter, which is the main constituent of spirit varnish, seems better adapted for this purpose. It is sufficiently combustible, and may be yet made by a due proportion, to soften the violence of the explosive mercury on the nipple of the touch-hole. Fulminate prepared by my formula has no corrosive influence whatsoever on iron or steel; and, therefore, if such a medium of applying it, as I have now taken leave to suggest, should be found to answer, all fears on the score of corrosion may for ever be set at rest.

_Question 4._ How far is the mixture (of fulminate and gunpowder) liable to be affected by the moisture of the atmosphere, or by the intrusion of water; and will such an accident affect its inflammability when dried again?

_Answer._ Well made fulminate, mixed with gunpowder and moistened, undergoes no change, nor is it apt to get deteriorated by keeping any length of time in a damp climate or a hazy atmosphere. Immersion in water would be apt to wash the nitre out of the pulverine; but this result would be prevented if the match or priming mixture were liquefied or brought to the pasty consistence not with water, but spirit varnish. Such detonating caps would be indestructible, and might be alternately moistened and dried without injury.

_Question 5._ Is it at all probable that the composition would be rendered more inflammable or dangerous of use, by the heat of tropical climates?

_Answer._ No elevation of temperature of an atmospheric kind, compatible with human existence, could cause spontaneous combustion of the fulminating mercury, or the detonating matches made with it. In fact, its explosive temperature is so high as 367° of Fahrenheit’s scale, and no inferior heat will cause its detonation.

_Question 6._ Is the mercurial vapour or gas arising from the ignition of a great number of primers, and combined with the smoke of gunpowder in a confined space (as in the case of troops in close bodies, squares, casemates, &c.) likely in its nature to be found prejudicial to human health?

_Answer._ I have exploded in rapid succession of portions, 100 grains of fulminate of mercury (equivalent to 300 or 400 primers), in a close chamber of small dimensions, without experiencing the slightest inconvenience at the period, or afterwards, though my head was surrounded by the vapours all the time of the operation. These vapours are, in fact, so heavy that they subside almost immediately. When the fulminate mixed with pulverine is exploded in the primers by condensed masses of troops, the mercury will cause no injury to their health, nor one 100th part of the deleterious impression on weak lungs which the gases of exploded gunpowder might by possibility inflict. These gases are all, _theoretically_ speaking, noxious to respiration; such as carbonic acid gas, azote, carburetted hydrogen, and sulphuretted hydrogen, a deadly gas. Yet the soldier who should betray any fear of gunpowder smoke would be an object of just ridicule.”

In the following September, I executed for the Board of Ordnance a set of experiments complementary to those of the memoir, with the view of ascertaining the best manner of protecting the fulminate when applied to the copper caps, from being detached by carriage, or altered by keeping. The following were my results and conclusions.

1. Fulminate of mercury moistened upon copper is speedily decomposed by the superior affinity of the copper over mercury, for oxygen and fulminic acid. Dryness is, therefore, essential to the preservation of the fulminate; and hence charcoal, which is apt to become moist, should not be introduced into percussion caps destined for distant service.

2. An alcoholic solution of sandarach, commonly called spirit varnish, acts powerfully on copper, with the production of a green efflorescence, which decomposes fulminate of mercury. Indeed, sandarach can decompose the salts of copper. It is therefore ill adapted for attaching the fulminate to copper caps.

3. An alcoholic solution of shell-lac acts on copper, though more feebly than the sandarach.

4. A solution of mastic in spirits of turpentine, whether alone or mixed with fulminate, has no action whatever on bright copper, but protects it from being tarnished. Such a varnish is very cheap, dries readily, adheres strongly, screens the fulminate from damp, and does not impair or counteract its detonating powers. This, therefore, is in my opinion the fittest medium for attaching the fulminate, and for softening the force of its impulsion in any degree proportional to the thickness of the varnish.”

Fulminate of mercury is obtained in white grains, or short needles, of a silky lustre, which become gray upon exposure to light, and detonate either by a blow or at a heat under 370° F.; with the disengagement of azote, carbonic acid, as also of aqueous and mercurial vapours; to the sudden formation of which gaseous products the report is due. It detonates even in a moist condition; and when dry it explodes readily when struck between two pieces of iron, less so between iron and bronze, with more difficulty between marble and glass, or between two surfaces of marble or glass. It is hardly possible to explode it by a blow with iron upon lead; and impossible by striking it with iron upon wood. It fulminates easily when rubbed between two wooden surfaces; less so between two of marble, two of iron, or one of iron against one of wood or marble. The larger its crystals, the more apt they are to explode. By damping it with 5 per cent. of water, it becomes less fulminating; the part of it struck still explodes with a proper blow, but will not kindle the adjoining portion. Though moistened with 30 per cent. of water, it will occasionally explode by trituration between a wooden muller and a marble slab, but only to a small extent, and never with any danger to the operator. When an ounce of it, laid upon the bottom of a cask, is kindled, it strikes a round hole down through it, as if it had been exposed to a four-pound shot, without splintering the wood. If a train of fulminate of mercury be spread upon a piece of paper, covered with some loose gunpowder, in exploding the former the latter will not be kindled, but merely scattered. When gunpowder, however, is packed in a cartridge, or otherwise, it may be certainly kindled by a percussion cap of the fulminate, and more completely than by a priming of gunpowder. 8-1/2 parts of gunpowder exploded by a percussion cap, have an equal projectile force as 10 exploded by a flint lock. If we add to this economy in the charge of the barrel, the saving of the powder for priming, the advantage in military service of the percussion system will become conspicuous.

The French calculate that 1 kilogramme of mercury will furnish 1-1/4 kil. (2-1/2 lbs. nearly) of fulminate, which will be sufficient to charge 40,000 percussion caps. For this purpose they grind the crystalline salt along with 30 per cent. of water upon a marble table with a wooden muller; mixing with every 10 parts of the fulminate 6 of gunpowder. A consistent dough is thus obtained, which, being dried in the air, is ready for introducing into the bottoms of the copper caps. One quarter of a grain of the fulminate is said to be fully sufficient for one priming.

Mr. Lovell, of the Royal Manufactory of Arms, has lately executed a series of experiments upon priming powders. His trials, which occupied nearly 18 months, were made for the purpose of ascertaining what is the advantage in point of _force_ obtained by using percussion primes. He had anticipated some extra energy would be imparted to the charge of powder in the barrel, because he had repeatedly proved that a good strong cap, exploded by itself on the nipple of the musquet, (without any charge of gunpowder), will exert sufficient force upon the air within the barrel to blow a candle out at a distance of 12 feet from the muzzle. He concluded also that stopping the escape of fluid from the vent, as is done by the cap, would have some effect, but he attributed most to the quickness and energy with which the powder of the charge is ignited by the vivid stream of flame, generated by the percussion prime. The trials were made from one and the same barrel, having a percussion lock on one side and a flint lock on the other. The balls were fired against Austen’s recoiling target, a very delicate _plegometer_, beginning with a charge of 150 grains (the present musquet charge), and descending by 10 grains at a time (firing 30 rounds with each weight), down to 50 grains. The machine marked the decrease of force at each reduction in the charge very satisfactorily, and the result of the whole average was that 8·84 parts of gunpowder fired by percussion are equal to 10 parts fired by the flint.

To find out what sort of liberties might be taken with fulminate of mercury in handling it, he placed 3 grains on an anvil, putting the end of a steel punch gently on the top of it, and while so placed he covered the fulminate over with a drachm of dry gunpowder. He then ignited the fulminate by a blow on the punch with the hammer, but not a grain of the gunpowder was lighted, though it was blown about in all directions. He then placed a train of fulminate as thick as a quill, and about 3 feet long, on a table, and covered it over entirely with gunpowder except about an inch at one end; this he lighted with a hot iron, when the whole train went off without blazing a grain of the gunpowder, which he swept together and blew up afterwards with a match. He then took a tin box containing 500 copper caps, made a hole in the top of the box, and through this hole ignited one of the caps in the middle, by means of the punch and hammer on the outside; only two other caps besides the one struck exploded; no injury was sustained by the remainder, except being discoloured. This he tried repeatedly, and always with the same kind of result, never more than 3 or 4 caps exploding. He then made a steel rammer red hot, and passed it through the hole in the box right in amongst the caps, but it only ignited them where the hot iron came in actual contact with the priming composition; when, however, he placed a few grains of gunpowder loose among the caps, the hot iron lighted this, and produced a flame that blew off the whole of them.

The same thing has been tried at Woolwich, where large packages of percussion caps (some thousands) have been fired at with musquet balls, and only a few of the caps actually hit by the ball exploded; but when any cartridges were connected with the packages, the whole, caps and all were blown up. The flame of the fulminate is therefore hazardous, but being so very ethereal, it requires for making primes, an admixture of some combustible matter, as a little gunpowder, to condense or modify the flame.

FULMINIC ACID; (_Acide fulminique_, Fr.; _Knallsäure_, Germ.) is the explosive constituent of the fulminating mercury of Howard, and the fulminating silver of Brugnatelli, being generated by the reaction of alcohol and the acid nitrates of these metals. It is a remarkable chemical fact, that fulminic acid has exactly the same composition as cyanic acid; though the salts of the latter possess no detonating property, and afford, in their decomposition by an oxygen acid, ammonia with carbonic acid; while those of the former afford ammonia and prussic acid. All attempts to insulate fulminic acid have proved unsuccessful, as it explodes with the slightest decomposing force. It consists, by weight, of 2 primes of carbon, 1 of azote, and 1 of oxygen; or of two volumes of carbonic acid, and one of azote. When two different bodies, like the above, have the same composition, they are said to be _isomeric_.

FUMIGATION, is the employment of fumes or vapours to purify articles of apparel, and goods or apartments supposed to be imbued with some infectious or contagious poison or fumes. The vapours of vinegar, the fumes of burning sulphur, explosion of gunpowder, have been long prescribed and practised, but they have in all probability little or no efficacy. The diffusion of such powerful agents as chlorine gas, muriatic acid gas, or nitric acid vapour, should alone be trusted to for the destruction of morbific effluvia.

FUR; see PELTRY.

FURNACE OF ASSAY. Under ASSAY, I have referred to a furnace constructed by Messrs. Anfrye and d’Arcet, which gives some peculiar facilities and economy to the ancient process by fire. It had originally a small pair of bellows attached to it, for raising the heat rapidly to the proper vitrifying pitch. The furnace, 17-1/2 inches high, and 7-1/2 inches wide, made of pottery or fine clay, is represented _fig._ 481., supported upon a table, having a pair of bellows beneath it. The laboratory is at _b_, the blow-pipe of the bellows at _d_, with a stop-cock, and the dome is surmounted by a chimney _a_, _c_, in whose lower part there is an opening with a sliding door, for the introduction of the charcoal fuel. The furnace is formed in three pieces; a dome, a body, and an ash-pit. A pair of tongs, a stoking hook, and cupel, are seen to the right hand, and the plan of the stone-ware grate, pierced with conical holes, and a poker, are seen to the left. This grate suits the furnace represented under ASSAY. The following are comparative experiments made by means of this furnace:

+--------+---------+---------+-----------+--------------+-----------+
|Numbers.| Silver | Lead | Time of | Standards. | Charcoal |
| |employed.|employed.| Assay. | | used. |
+--------+---------+---------+-----------+--------------+-----------+
| 1 |1 Grain. |4 Grains.|12 minutes.|947 millièmes.|173 Grains.|
| 2 | -- | -- |11 |950 | 86 |
| 3 | -- | -- |13 |949 | 93 |
| 4 | -- | -- |10 |949 | 60 |
+--------+---------+---------+-----------+--------------+-----------+

Each assay was therefore performed at an average in 11-1/2 minutes, and not much more than a quarter of a pound of charcoal was used. An experiment of verification in the ordinary assay furnace showed the standard to be 949 thousandths.

This furnace becomes a very convenient one for melting small quantities of metals in analyses, by removing the muffle, and closing the several apertures with their appropriate stoppers. A small pedestal may be then set in the middle of the grate, to support a crucible, which may be introduced through the opening _h_. Coak may also be used as fuel, either by itself or mixed with charcoal. For descriptions of various furnaces, see ASSAY; BEER; COPPER; EVAPORATION; IRON; METALLURGY; ORES; SILVER; TIN; &c.

FUSIBILITY. That property by which solids assume the fluid state.

Some chemists have asserted that fusion is simply a solution in caloric; but this opinion includes too many yet undecided questions, to be hastily adopted.

_Fusibility of Metals, as given by M. Thenard._

Centigr.
1. Fusible below a Mercury -39°
red heat. Potassium +58° } Gay Lussac and Thenard.
Sodium 90 }
Tin 210 } Newton.
Bismuth 256 }
Lead 260 Biot.
Tellurium A little less fusible than lead.--
Klaproth.
Arsenic Undetermined.
Zinc 370° Brongniart.
Antimony A little below a red heat.
Cadmium Stromeyer.

Pyrometer of Wedgewood.

2. Infusible below Silver 20° Kennedy.
a red heat. Copper 27 } Wedgewood.
Gold 32 }
Cobalt A little less difficult to melt than
iron.
Iron {130 Wedgewood.
{158 Sir G. M’Kenzie.
Manganese 160 Guyton.
Nickel As manganese.--Richter.
Palladium }
Molybdenum } Nearly infusible; and to be obtained
Uranium } at a forge heat only in small
Tungsten } buttons.
Chromium }
Titanium }
Cerium }
Osmium } Infusible at the forge furnace.
Iridium } Fusible at the oxyhydrogen blowpipe.
Rhodium } See BLOWPIPE.
Platinum }
Columbium }

FUSIBLE METAL. See ALLOY.

FUSTET. (_Fustec_, Fr.) The wood of the _rhus cotinus_, a fugitive yellow dye.

FUSTIAN, is a species of coarse thick tweelled cotton, and is generally dyed of an olive, leaden, or other dark colour. Besides the common fustian, which is known by the name of pillow (probably pilaw), the cotton stuffs called corduroy, velverett, velveteen, thicksett, used for men’s wearing apparel, belong to the same fabric. The commonest kind is merely a tweel of four, or sometimes five leaves, of a very close stout texture, and very narrow, seldom exceeding 17 or 18 inches in breadth. It is cut from the loom in half pieces, or ends as they are usually termed, about 35 yards long, and after undergoing the subsequent operations of dyeing, dressing, and folding, is ready for the market.

The draught and cording of common fustian is very simple, being generally a regular or unbroken tweel of four or five leaves. Below are specimens of a few different kinds, selected from those most general in Lancashire.

The number of leaves of heddles are represented by the lines across the paper, and the _cording_ by the cyphers in the little squares, those which raise every leaf being distinguished by these marks, and those which sink them left blank, as more particularly explained in the article TEXTILE FABRIC.

Of velvet, there are properly only two kinds, that with a plain, and that with a tweeled, or, as it is here called, a Genoa ground, or back. When the material is silk, it is called velvet, when cotton, velveteen; and this is the sole difference. In the same way a common tweeled cloth, when composed of silk is called satin; when of cotton, fustian or jean; of woollen, plaiding, serge, or kerseymere; and in the linen trade is distinguished by a variety of names according to the quality or fineness, or the place where the article is manufactured.

No. 1.--Pillow Fustian. No. 2.--Plain Velveret.
-+-+-+-+-+------------------------------+-+-+-+-+-+--------------
|0| | | | 4 5 1 § | |0| | | | 3 1
-+-+-+-+-+------------------------------+-+-+-+-+-+--------------
| |0| | | 3 6 2 § |0| | | | | 5
-+-+-+-+-+------------------------------+-+-+-+-+-+--------------
| | |0| | 6 2 3 § |0| | |0|0| 0 2
-+-+-+-+-+------------------------------+-+-+-+-+-+--------------
| | | |0| 5 1 4 § | | | |0| | 6 4
-+-+-+-+-+------------------------------+-+-+-+-+-+--------------
2 4 3 1 4 6 2 3 1
5

Of the above, each contains four leaves of heddles or healds; that represented by No. 1. is wrought by four treddles, and that which is distinguished by No. 2. by five; the succession of inserting the threads of warp into the heddles will be discovered by the figures between the lines, and the order in which the treddles are to be successively pressed down by the figures below.

No. 3.--Double Jean. No. 4.--Plain Thicksett.
-+-+-+-+-+----------------------+-+-+-+-+-+----------------
|0| | |0| 1 § | |0| | | | 8
-+-+-+-+-+----------------------+-+-+-+-+-+----------------
|0| |0| | 2 § | |0|0|0| | 6 4
-+-+-+-+-+----------------------+-+-+-+-+-+----------------
| |0|0| | 3 § | | | |0| | 5 2
-+-+-+-+-+----------------------+-+-+-+-+-+----------------
| |0| |0| 4 § |0| | |0|0| 7 3 1
-+-+-+-+-+----------------------+-+-+-+-+-+----------------
4 2 3 1 4 6 2 3 1
5 7

These, like the former, are wrought with leaves. No. 3. requires four, and No. 4. five treddles. The succession of inserting the threads of warp, and of working the treddles, are marked by the respective numbers between and under the lines, as in the former example. Both are fabrics of cloth in very general use and estimation as low priced articles.

No. 5.--Best Thicksett. No. 6.--Velvet Tuft.
-+-+-+-+-+-+------------------+-+-+-+-+-+---------------------
|0| | |0|0| 3 1 § | |0| | | | 5 3 1
-+-+-+-+-+-+------------------+-+-+-+-+-+---------------------
| | | | |0| 5 § | |0|0| | | 4 2
-+-+-+-+-+-+------------------+-+-+-+-+-+---------------------
| |0| | | | 2 § |0| | |0|0| 4 2
-+-+-+-+-+-+------------------+-+-+-+-+-+---------------------
| |0|0| | | 6 4 § | | | |0| | 5 3 1
-+-+-+-+-+-+------------------+-+-+-+-+-+---------------------
6 4 2 3 1 6 4 2 3 1
5

These are further specimens of what may be, and is, executed with four leaves, and in both examples five treddles are used. With two other specimens we shall conclude our examples of this description of work, and shall then add a very few specimens of the more extensive kinds.

No. 7.--Cord and Velveret. No. 8.--Thicksett Cord.
-+-+-+-+-+-+-----------------------------+-+-+-+-+-+-----------------
| |0| | | | 3 1 3 1 §|0| | |0|0| 5 3 1
-+-+-+-+-+-+-----------------------------+-+-+-+-+-+-----------------
| |0|0| | | 5 7 5 §| |0| | | | 4 2
-+-+-+-+-+-+-----------------------------+-+-+-+-+-+-----------------
|0| | |0|0|6 8 2 §| | | | | | 9 7
-+-+-+-+-+-+-----------------------------+-+-+-+-+-+-----------------
| | | |0| | 4 2 6 4 §| |0|0| | | 10 8 6
-+-+-+-+-+-+-----------------------------+-+-+-+-+-+-----------------
4 2 3 1 5 4 3 2 1
6 5

In these the succession of drawing and working are marked like the former. The next are examples of patterns wrought with six leaves. No. 9. has eight, and No. 10. five heddles.

No. 9.--Double Corduroy. No. 10.--Genoa Thicksett.
-+-+-+-+-+--+--+--+-+-----------------+-+-+--+-+-+--------------
| | | |0| |0 | |0| 1 § | | | |0|0| 1
-+-+-+-+-+--+--+--+-+-----------------+-+-+--+-+-+--------------
| |0| | | |0 | | | 2 § | | | 0| |0| 2
-+-+-+-+-+--+--+--+-+-----------------+-+-+--+-+-+--------------
|0|0|0|0|0 | | | | 3 § |0| | 0|0| | 3
-+-+-+-+-+--+--+--+-+-----------------+-+-+--+-+-+--------------
| | | |0| |0 | | | 4 § | |0| |0|0| 4
-+-+-+-+-+--+--+--+-+-----------------+-+-+--+-+-+--------------
| |0| | | | | 0| | 5 § |0| | 0| |0| 5
-+-+-+-+-+--+--+--+-+-----------------+-+-+--+-+-+--------------
| |0| |0| | | | | 6 § | |0| |0| | 6
-+-+-+-+-+--+--+--+-+-----------------+-+-+--+-+-+--------------
2 4 6 8 10 12 3 1 4 2 5 3 1
7 5 8 6 11 9 7
11 9 1 2 10

In both these the warp is inserted into the heddles the same way. The difference is entirely in the application of the cords, and in the succession of pressing down the treddles. We now give four specimens of the flushed and cut work, known by the name of velveteen. They are also upon six leaves, and the difference is solely in the cording and in the treading.

No. 11. Queen’s Velveteens. No. 12.
-+-+--+--+-+-+--+-----------------+--+--+--+-+-+-+-------------
| | 0| |0|0| | 1 § | | | |0| |0| 1
-+-+--+--+-+-+--+-----------------+--+--+--+-+-+-+-------------
| | | 0| |0| | 2 § | | | 0| |0|0| 2
-+-+--+--+-+-+--+-----------------+--+--+--+-+-+-+-------------
| | | 0|0| | | 3 § | | | |0|0| | 3
-+-+--+--+-+-+--+-----------------+--+--+--+-+-+-+-------------
| | | |0|0| 0| 4 § | | 0| |0| |0| 4
-+-+--+--+-+-+--+-----------------+--+--+--+-+-+-+-------------
| | | 0| |0| | 5 § | | | | |0|0| 5
-+-+--+--+-+-+--+-----------------+--+--+--+-+-+-+-------------
|0| | 0|0| | | 6 § | 0| | |0|0| | 6
-+-+--+--+-+-+--+-----------------+--+--+--+-+-+-+-------------
1 2 12 8 4 2 2 4 3 1
5 7 6 6 8 7 5
9 11 10 10 12 11 9

No. 13.--Plain Velveteen. No. 14.--Genoa Velveteen.
-+-+-+-+-+-+-----------------+--+-+-+--+--+-+-------------
| | | | |0| 1 § | | |0| 0| |0| 1
-+-+-+-+-+-+-----------------+--+-+-+--+--+-+-------------
|0| | |0| | 2 § | |0|0| | | | 2
-+-+-+-+-+-+-----------------+--+-+-+--+--+-+-------------
| | | | |0| 3 § | 0|0| | 0| | | 3
-+-+-+-+-+-+-----------------+--+-+-+--+--+-+-------------
| | |0|0| | 4 § | | |0| 0| | | 4
-+-+-+-+-+-+-----------------+--+-+-+--+--+-+-------------
| | | | |0| 5 § | |0|0| | 0| | 5
-+-+-+-+-+-+-----------------+--+-+-+--+--+-+-------------
| |0| |0| | 6 § | |0| | 0| | | 6
-+-+-+-+-+-+-----------------+--+-+-+--+--+-+-------------
1 3 2 4 8 2 4 8 12 3 1
5 7 6 6 7 5
10 11 9

The additional varieties of figure which might be given are almost endless, but the limits of this article will not admit a further detail. Those already given are the articles in most general use. The varieties of fancy may be indulged to great extent, but it is universally found, that the most simple patterns in every department of ornamental weaving, are those which attract attention and command purchasers. We shall therefore only add two examples of king’s cord or corduroy, two of Genoa and common velvet, and two more of jean. These will be found below.

No. 15.--King’s Cord. No. 16.--Dutch Cord.
-+-+-+-+-+-+-+---------------------+-+-+-+-+-+------------------
| | | | |0|0| 1 § | | |0| | | 4 1
-+-+-+-+-+-+-+---------------------+-+-+-+-+-+------------------
| | |0| | |0| 2 § | |0| | |0| 5 2
-+-+-+-+-+-+-+---------------------+-+-+-+-+-+------------------
| | |0|0| | | 7 3 § |0| | |0| | 6 3
-+-+-+-+-+-+-+---------------------+-+-+-+-+-+------------------
| | | |0|0| | 8 4 § | |0|0| | | 7
-+-+-+-+-+-+-+---------------------+-+-+-+-+-+------------------
| |0| | |0|0| 5 § |0| |0| |0| 8
-+-+-+-+-+-+-+---------------------+-+-+-+-+-+------------------
|0| |0| | | | 6 § |0|0| |0|0| 9
-+-+-+-+-+-+-+---------------------+-+-+-+-+-+------------------
1 3 8 6 4 2 6 4 2 3 1
5 7 5

No. 17.--Genoa Velvet. No. 18.--Plain Velvet.
-+--+-+-+--+--+-+-----------------+-+-+-+-+-+-------------
| | |0| | |0| 1 § | | | | | | 1
-+--+-+-+--+--+-+-----------------+-+-+-+-+-+-------------
| |0|0| 0| | | 2 § | | | | | | 2
-+--+-+-+--+--+-+-----------------+-+-+-+-+-+-------------
| 0|0| | | | | 3 § | | | | | | 3
-+--+-+-+--+--+-+-----------------+-+-+-+-+-+-------------
| | |0| 0| | | 4 § | | | | | | 4
-+--+-+-+--+--+-+-----------------+-+-+-+-+-+-------------
| |0| | 0| | | 5 § | | | | | | 5
-+--+-+-+--+--+-+-----------------+-+-+-+-+-+-------------
| |0| | 0| | | 6 § | | | | | | 6
-+--+-+-+--+--+-+-----------------+-+-+-+-+-+-------------
2 4 8 12 3 1 1 3 4 2 8
6 7 5 7 5
10 11 9

After the fustian cloth is taken from the loom-beam, it is carried to the cutter, who rips up the surface-threads of weft, and produces thereby a hairy-looking stuff.

Preparatory to its being cut, the cloth is spread evenly upon a table about six feet long, upon each end of which a roller mounted with a ratchet-wheel is fixed; the one to give off, and the other to wind up the piece, in the above six-feet lengths.

The knife is a steel rod about two feet long, and three-eighths of an inch square, having a square handle at the one end; the other end is tapered away to a blade, as thin as paper. To prevent this point from turning downwards and injuring the cloth, its under side is covered by a guide which serves to stiffen it, as well as to prevent its lower edge from cutting the fustian.

The operative (male or female) grasps the handle in the right hand, and insinuating the projecting point of the guide under the weft, pushes the knife smartly forward through the whole length of six feet, with a certain dexterous movement of the shoulder and right side, balancing the body meanwhile, like a fencer, upon the left foot. This process is repeated upon every adhesive line of the weft.

The next process to which fustians are exposed is steeping in hot water, to take out the dressing paste. They are then dried, reeled, and brushed by a machine, &c. From twenty to thirty pieces, each eighty yards long, may be brushed in an hour. The breadth of the cloth is twenty inches. The maceration is performed by immersing the bundled pieces in tanks of water, heated by waste steam; and the washing by means of a reel or winch, kept revolving rapidly under the action of a stream of cold water, for an hour or longer.

After being thus ripped up, it is taken to the brushing or teazling machine, to make it shaggy.

This consists of a series of wooden rollers, turning freely upon iron axles, and covered with tin-plate, rough with the burs of punched holes; and blocks of wood, whose concave under surfaces are covered with card-cloth or card-brushes, and which are made to traverse backwards and forwards in the direction of the axes of the revolving rollers, during the passage of the cloth over them.

After they are brushed in the machine, the goods are singed by passing their cut surface over a cylinder of iron, laid in a horizontal direction, and kept red hot by a flue. See SINGEING. They are now brushed again by the machine, and once more passed over the singeing surface. The brushing and singeing are repeated a third or even occasionally a fourth time, till the cord acquires a smooth polished appearance.

The goods are next steeped, washed, and bleached, by immersion in solution of chloride of lime. They are then dyed by appropriate chemical means. After which they are padded (imbued by the padding machine of the calico printers) with a solution of glue, and passed over steam cylinders to stiffen them.

Smooth fustians, when cropped or shorn before dyeing, are called moleskins; but when shorn after being dyed, are called beaverteen, they are both tweeled fabrics. Cantoon is a fustian with a fine cord visible upon the one side, and a satiny surface of yarns running at right angles to the cords upon the other side. The satiny side is sometimes smoothed by singeing. The stuff is strong, and has a very fine aspect. Its price is one shilling and sixpence a yard.

Common plain fustian, of a brown or drab colour, with satin top, is sold as low as sevenpence a yard.

A fustian, with a small cord running in an oblique direction, has a very agreeable appearance. It is called diagonal. Moleskin shorn, of a very strong texture, and a drab dyed tint, is sold at 20_d_. per yard.

The weight of 90 yards of the narrow velveteen, in the green or undressed state, is about 24 pounds. The goods made for the German, Italian, and Russian markets are lighter, on account of the peculiarity in the mode of levying the import duty in these countries.

Velveteens as they come from the loom, are sold wholesale by weight, and average a price of 20_d._ per pound. They are usually woven with yarns of Upland and Brazil cotton wool, spun together for the warp; or, sometimes, New Orleans alone. The weft is usually Uplands, sometimes mixed with East India cotton wools.

Trowser velveteens are woven 19 inches wide, if they are to be cut up; if not, they are woven 30 inches, and called beaverteen.

Cutting or cropping fustians by hand is a very laborious and delicate operation. The invention of an improved apparatus for effecting the same end with automatic precision and despatch, was therefore an object of no little interest to this peculiar manufacture of Manchester. An ingenious machine, apparently well calculated for this purpose, was made the subject of a patent by Messrs. William Wells and George Scholefield, of Salford in November, 1834.

FUSTIC. (_Bois jaune_, Fr.; _Gelbholz_, Germ.) The _old_ fustic of the English dyer, as the article fustet is their _yellow_ fustic. It is the wood of the Morus tinctoria. It is light, not hard, and pale yellow with orange veins; it contains two colouring matters, one resinous, and another soluble in water. The latter resembles weld, but it has more of an orange cast, and is not so lively.

Its decoctions in water are brightened by the addition of a little glue, and more by curdled milk. This wood is rich in colour, and imparts permanent dyes to woollen stuffs, when aided by proper mordants. It unites well with the blue of the indigo vat, and Saxon blue, in producing green of various shades. Alum, tartar, and solution of tin, render its colour more vivid; sea salt and sulphate of iron deepen its hue. From 5 to 6 parts of old fustic are sufficient to give a lemon colour to 16 parts of cloth. The colour of weld is however purer and less inclining to orange; but that of fustic is less affected by acids than any other yellow dye. This wood is often employed with sulphate of iron in producing olive and brownish tints, which agree well with its dull yellow. For the same reason it is much used for dark greens.

G.

GABRONITE, is a yellowish stony substance, of a greasy lustre and spec. gr. = 2·74; affording no water by calcination; fusible at the blowpipe into an opaque glass; soluble in muriatic acid; solution affords hardly any precipitate by oxalate of ammonia. This mineral is distinguished by the large quantity of soda which it contains; its constituents being,--silica, 54; alumina, 24; soda, 17·25; magnesia, 1·5; oxide of iron, 1·25; water, 2. It belongs to the species Nepheline.

GADOLINITE; called also Yttrite and Ytterbite; is a mineral of a black, brownish, or yellowish colour, granular, or compactly vitreous, and conchoidal fracture; of spec. grav. 4·23? readily scratching glass; fusible at the blowpipe into an opaque glass, sometimes with intumescence. It affords, with acids, a solution that lets fall, with caustic soda, a precipitate partly re-soluble in carbonate of ammonia. It is remarkable for containing from 45 to 55 per cent. of the earth Yttria; its remaining constituents being silica, 25·8; oxide of cerium, 17·92; oxide of iron, 11·43. This mineral is very rare, having been hitherto found only in the neighbourhood of Fahlun and Ytterby, in Sweden; its peculiar constituent was discovered by Professor Gadolin.

GALACTOMETER, or LACTOMETER, is an instrument to ascertain the quality of milk; an article often sophisticated in various ways. Fresh milk, rich in cream, has a less specific gravity, than the same milk after it has been skimmed; and milk diluted with water becomes proportionably lighter. Hence, when our purpose is to determine the quantity of cream, the galactometer may consist merely of a long graduated glass tube standing upright upon a sole. Having filled 100 measures with the recent milk, we shall see, by the measures of cream thrown up, its value in this respect. A delicate long-ranged glass hydrometer, graduated from 1·000 up to 1·060, affords the most convenient means of detecting the degree of watery dilution, provided the absence of thickening materials has been previously ascertained by filtration. Good fresh milk indicates from 1·030 to 1·032; when the cream is removed, 1·035 to 1·037. When its density is less than 1·028, we may infer it has been thinned with water.

GALBANUM, is a gum-resin, which occurs sometimes in yellow, shining tears, easily agglutinated; of a strong durable smell; an acrid and bitter taste; at other times in lumps. It exudes either spontaneously or from incisions made into the stem of the _bubon galbanum_, a plant of the family of _umbelliferæ_, which grows in Africa, particularly in Ethiopia. It contains 67 of resin; 19·3 of gum; 6·4 of volatile oil and water; 7·5 of woody fibres and other impurities; with traces of acid malate of lime.

GALENA; (_Plomb sulfuré_, Fr.; _Bleiglanz_, Germ.;) is a metallic looking substance of a lead-gray colour, which crystallizes in the cubical system, and is susceptible of cleavages parallel to the faces of the cube; spec. gr. 7·7592; cannot be cut; fusible at the blowpipe with exhalation of sulphureous vapours; is easily reduced to metallic lead. Nitric acid first dissolves it, and then throws down sulphate of lead in a white precipitate; the solution affording with plates of zinc, brilliant laminæ of lead (arbor Saturni.) It consists of sulphur, 13; lead, 85; with a little iron, and sometimes a minute quantity of silver. This is the richest ore of lead, and it occurs in almost every geological formation, in veins, in masses, or in beds. It is almost always accompanied by sulphuret of zinc, different salts of lead, heavy spar, fluor spar, &c. Galena in powder, called Alquifoux, is employed as a glaze for coarse stoneware.

GALIPOT, is a name of a white semi-solid viscid rosin found on fir-trees; or an inferior sort of turpentine, poor in oil.

GALLATES; salts consisting of gallic acid combined with bases; the most important being that with oxide of iron, constituting a principal part of the black dye.

GALLIC ACID, is the peculiar acid extracted from gall-nuts; which see.

GALLIPOLI OIL, is a coarse olive oil, containing more or less mucilage; imported from a sea port so named, of the province of Otranto, in the kingdom of Naples.

GALL-NUTS, or GALLS; (_Noix de Galle_, Fr.; _Galläpfel_, Germ.;) are excrescences found upon the loaves and leaf-stalks of a species of oak, called _Quercus infectoria_, which grows in the Levant. They are produced in consequence of the puncture of the female of the gall wasp, (Cynips folii quercus), made in order to deposit her eggs; round which the juice of the tree exudes, and dries in concentric portions. When the insect gets fully formed, it eats through the nut, and flies off.

The Levant galls are of two different appearances and qualities; the first are heavy, compact, imperforated, the insect having not been sufficiently advanced to eat its way through the shell; prickly on the surface; of a blackish or bluish green hue; about the size of a musket ball. These are called _black_, blue, or Aleppo galls. The second are light, spongy, pierced with one or more holes; smooth upon the surface, of a pale grayish or reddish yellow colour, generally larger than the first, and are called _white_ galls. Besides the galls of the Levant, others come from Dalmatia, Illyria, Calabria, &c.; but they are of inferior quality, being found upon the _Quercus Cerris_; they are smaller, of a brownish colour, and of inferior value. The further south the galls are grown, they are reckoned the better.

Galls consist principally of three substances; tannin or tannic acid; yellow extractive; and gallic acid. Their decoction has a very astringent and unpleasant bitter taste. The following are their habitudes with various reagents:--

Litmus paper is powerfully reddened.

Stannous chloride (_protomuriate of tin_), produces an isabel yellow precipitate.

Alum; a yellowish gray precipitate.

Acetate of lead; a thick yellowish white precipitate.

Acetate of copper; a chocolate brown precipitate.

Ferric sulphate (red sulphate of iron); a blue precipitate.

Sulphuric acid; a dirty yellowish precipitate.

Acetic acid brightens the muddy decoction.

The galls of the _Quercus Cerris_ and common oak (_Galles à l’épine_, Fr.; _Knoppern_, Germ.) are of a dark-brown colour, prickly on the surface, and irregular in shape and size. They are used chiefly for tanning in Hungary, Dalmatia, and the southern provinces of the Austrian states, where they abound.

Tannin or tannic acid is prepared as follows: Into a long narrow glass adopter tube shut at its lower orifice with a cotton wick, a quantity of pounded galls are put, and slightly pressed down. The tapering end of the tube being inserted into a matrass or bottle, the vacant upper half of the tube is filled with sulphuric ether, and then closed with a ground-glass stopper. Next day there will be found in the bottle a liquid in two distinct strata; of which the more limpid occupies the upper part, and the other, of a syrupy consistence and amber colour, the lower. More ether must be filtered through the galls, till the thicker liquid ceases to augment. Both are now poured into a funnel, closed with the finger, and after the dense liquor is settled at the bottom, it is steadily run off into a capsule. This, after being washed repeatedly with ether, is to be transferred into a stove chamber, or placed under the receiver of an air pump to be evaporated. The residuary matter swells up in a spongy crystalline form of considerable brilliancy, sometimes colourless, but more frequently of a faintly yellowish hue.

This is pure tannin, which exists in galls to the amount of from 40 to 45 per cent. It is indispensable that the ether employed in the preceding process be previously agitated with water, or that it contain some water, because by using anhydrous ether, not a particle of tannin will be obtained.

Tannic acid is a white or yellowish solid, inodorous, extremely astringent, very soluble in water and alcohol, much less so in sulphuric ether, and uncrystallizable. Its watery solution, out of contact of air, undergoes no change; but if, in a very dilute state, it be left exposed to the atmosphere, it loses gradually its transparency, and lets fall a slightly grayish crystalline matter, consisting almost entirely of gallic acid. For procuring this acid in a perfectly pure state, it is merely necessary to treat that solution thus changed with animal charcoal, and to filter it in a boiling state, through paper previously washed with dilute muriatic acid. The gallic acid will fall down in crystals as the liquid cools.

If the preceding experiment be made in a graduated glass tube containing oxygen over mercury, this gas will be absorbed, and a corresponding volume of carbonic acid gas will be disengaged. In this case the liquor will appear in the course of a few weeks as if traversed with numerous crystalline colourless needles of gallic acid.

Tannin or tannic acid consists of carbon 51·56; hydrogen 4·20; oxygen 44·24.

From the above facts it is obvious that gallic acid does not exist ready formed in gall nuts, but that it is produced by the reaction of atmospheric oxygen upon the tannin of these concretions.

Gallic acid is a solid, feebly acidulous and styptic to the taste, inodorous, crystallizing in silky needles of the greatest whiteness; soluble in about 100 times its weight of cold, and in a much smaller quantity of boiling water; more soluble in alcohol than in water, but little so in sulphuric ether.

Gallic acid does not decompose the salts of protoxide of iron, but it forms, with the sulphate of the peroxide, a dark blue precipitate, much less insoluble than the tannate of iron. Gallic acid takes the oxide from the acetate and nitrate of lead, and throws down a white gallate unchangeable in the air, when it is mixed with that acetate and nitrate. It occasions no precipitate in solutions of gelatine (isinglass or glue), by which criterion its freedom from tannin is verified.

Gallic acid occurs but seldom in nature; and always united to brucine, veratrine, or lime. Its constituents are, carbon 49·89; hydrogen 3·49; oxygen 46·62. In the crystalline state it contains one atom of water, which it loses by drying.

Scheele obtained gallic acid by infusing pounded galls for 3 or 4 days in 8 times their weight of water, and exposing the infusion to the air, in a vessel covered loosely with paper. At the end of two months, the liquor had almost all evaporated, leaving some mouldiness mixed with a crystalline precipitate. The former being removed, the deposit was squeezed in a linen cloth, and then treated with boiling water. The solution being gradually evaporated, yielded crystals of gallic acid, granular or star-like, of a grayish colour. These crystals might be whitened by boiling their solution along with a little animal charcoal. About one fifth of gallic acid may be obtained by Scheele’s process from good gall-nuts.

From a decoction of 500 parts of galls, Sir H. Davy obtained 185 parts of solid extract; which consisted of 130 parts of tannin; 31 parts of gallic acid with extractive; 13 parts of mucilage; 12 parts of lime and salts. Hence gall-nuts would seem to contain, by this statement, more than two-thirds of their weight of tannin. This result is now seen, from the above experiments of Pelouze, to have been incorrect, in consequence of the admixture of yellow extractive in Davy’s tannin.

The uses of galls in many processes of dyeing, and in making black ink, are detailed under their respective heads.

GALL OF ANIMALS, or OX-GALL, _purification of_. Painters in water colours, scourers of clothes, and many others employ ox-gall or bile, but when it is not purified, it is apt to do harm from the greenness of its own tint. It becomes therefore an important object to clarify it, and to make it limpid and transparent like water. The following process has been given for that purpose. Take the gall of newly killed oxen, and after having allowed it to settle for 12 or 15 hours in a basin, pour the supernatant liquor off the sediment into an evaporating dish of stone ware, and expose it to a boiling heat in a water bath, till it is somewhat thick. Then spread it upon a dish, and place it before a fire till it becomes nearly dry. In this state it may be kept for years in jelly pots covered with paper, without undergoing any alteration. When it is to be used, a piece of it of the size of a pea is to be dissolved in a table spoonful of water.

Another and probably a better mode of purifying ox-gall is the following. To a pint of the gall boiled and skimmed, add one ounce of fine alum in powder, and leave the mixture on the fire till the alum be dissolved. When cooled, pour into a bottle, which is to be loosely corked. Now take a like quantity of gall also boiled and skimmed, add an ounce of common salt to it, and dissolve with heat; put it when cold into a bottle, which is likewise to be loosely corked. Either of these preparations may be kept for several years without their emitting a bad smell. After remaining three months, at a moderate temperature, they deposit a thick sediment, and become clearer, and fit for ordinary uses, but not for artists in water colours and miniatures, on account of their yellowish-green colour. To obviate this inconvenience, each of the above liquors is to be decanted apart, after they have become perfectly settled, and the clear portion of both mixed together in equal parts. The yellow colouring matter still retained by the mixture coagulates immediately and precipitates, leaving the ox-gall perfectly purified and colourless. If wished to be still finer, it may be passed through filtering paper; but it becomes clearer with age, and never acquires a disagreeable smell, nor loses any of its good qualities.

Clarified ox-gall combines readily with colouring matters or pigments, and gives them solidity either by being mixed with or passed over them upon paper. It increases the brilliancy and the durability of ultramarine, carmine, green, and in general of all delicate colours, whilst it contributes to make them spread more evenly upon the paper, ivory, &c. When mixed with gum Arabic, it thickens the colours without communicating to them a disagreeable glistering appearance; it prevents the gum from cracking, and fixes the colours so well that others may be applied over them without degradation. Along with lamp black and gum, it forms a good imitation of China ink. When a coat of ox-gall is put upon drawings made with black lead or crayons, the lines can no longer be effaced, but may be painted over safely with a variety of colours previously mixed up with the same ox-gall.

Miniature painters find a great advantage in employing it; by passing it over ivory, it removes completely the unctuous matter from its surface; and when ground with the colours, it makes them spread with the greatest ease, and renders them fast.

It serves also for transparencies. It is first passed over the varnished or oiled paper, and is allowed to dry. The colours mixed with the gall are then applied, and cannot afterwards be removed by any means.

It is adapted finally for taking out spots of grease and oil.

GALL OF GLASS, called also sandiver, is the neutral salt skimmed off the surface of melted crown glass; which, if allowed to remain too long, is apt to be reabsorbed in part, and to injure the quality of the _metal_, as the workmen call it.

GALVANIZED IRON, is the somewhat fantastic name newly given in France to iron tinned by a peculiar patent process, whereby it resists the rusting influence of damp air, and even moisture, much longer than ordinary tin plate. The following is the prescribed process. Clean the surface of the iron perfectly by the joint action of dilute acid and friction, plunge it into a bath of melted zinc, and stir it about till it be alloyed superficially with this metal; then take it out, and immerse it in a bath of tin, such as is used for making tin plate. The tin forms an exterior coat of alloy. When the metal thus prepared is exposed to humidity, the zinc is said to oxidize slowly by a galvanic action, and to protect the iron from rusting within it, whereby the outer tinned surface remains for a long period perfectly white, in circumstances under which iron tinned in the usual way would have been superficially browned and corroded with rust.

GAMBOGE; (_Gomme Gutte_, Fr.; _Gutti_, Germ.) is a gum resin, concreted in the air, from the milky juice which exudes from several trees. The _gambogia gutta_, a tree which grows wild upon the coasts of Ceylon and Malabar, produces the coarsest kind of gamboge; the _guttaefera vera_ (_Stalagmites cambogioides_) of Ceylon and Siam affords the best. It comes to us in cylindrical lumps, which are outwardly brown yellow, but reddish yellow within, as also in cakes; it is opaque, easily reducible to powder, of specific gravity 1·207, scentless, and nearly devoid of taste, but leaves an acrid feeling in the throat. Its powder and watery emulsion are yellow. It consists of 80 parts of a hyacinth red resin, soluble in alcohol; and 20 parts of gum; but by another analysis, of 89 of resin, and 10·5 of gum. Gamboge is used as a pigment, and in miniature painting, to tinge gold varnish; in medicine as a powerful purge. It should never be employed by confectioners to colour their _liqueurs_, as they sometimes do.

GANGUE. A word derived from the German _gang_, a vein or channel. It signifies the mineral substance which either encloses or usually accompanies any metallic ore in the vein. Quartz, lamellar carbonate of lime, sulphate of baryta, sulphate and fluate of lime, generally form the gangues; but a great many other substances become such when they predominate in a vein. In metallurgic works the first thing is to break the mixed ore into small pieces, in order to separate the valuable from the useless parts, by processes called stamping, picking, sorting. See METALLURGY and MINES.

GARNET (_Grenat_, Fr.; _Granat_, Germ.); is a vitreous mineral of the cubic system, of which the predominating forms are the rhomboidal dodecahedron and the trapœzohedron; specific gravity varying from 3·35 to 4·24; fusible at the blowpipe. Its constituents are, silica, 42; alumina, 20·0; lime, 34·0; protoxide of iron, 4. Garnets are usually disseminated, and occur in all the primitive strata from gneiss to clay slate. The finer varieties, noble garnet or Almandine, and the reddish varieties of Grossulaire (Essonite), are employed in jewellery; the first are called the Syrian or oriental; the others, hyacinth. In some parts of Germany garnets are so abundant as to be used as fluxes to some iron ores; in others, the garnet gravel is washed, pounded, and employed as a substitute for emery. The garnets of Pegu are most highly valued. Factitious garnets may be made by the following composition:--Purest white glass, 2 ounces; glass of antimony, 1 ounce; powder of cassius, 1 grain; manganese, 1 grain.

GAS (Eng. and Fr.; _Gaz_, Germ.); is the generic name of all those elastic fluids which are permanent under a considerable pressure, and at the temperature of zero of Fahrenheit. In many of them, however, by the joint influence of excessive cold and pressure, the repulsive state of the particles may be balanced or subverted, so as to transform the elastic gas into a liquid or a solid. For this most interesting discovery, we are indebted to the fine genius of Mr. Faraday.

The following table exhibits the temperatures and pressures at which certain gases are liquefied.