Imatges de pàgina
PDF
EPUB

other neighbouring gentlemen were induced to establish at Raikes, near Bolton, in Lancashire, a bleaching concern of very considerable magnitude.

Little doubt could now be entertained but that the new process would eventually be brought into general use. Therefore, in the year 1789 (a year after Dr. Taylor

some distance from the town, which had all the necessary conveniences for the business. Here a large establishment was formed in the course of the year 1788; but notwithstanding the support which the proprietors had thus received, the opposition of the old bleachers, and the inveterate prejudices the neighbourhood were so

had exhibited in Manchester such a favour-great, that Mons. Bonjour was under the necessity of addressing the National Bureau of Commerce on the occasion.

able specimen of the facilities of the new method) Berthollet published a very cir cumstantial account of the system, with ample directions to the manufacturers, respecting the construction of an improved apparatus for the purpose of preparing the bleaching liquid.

ganese.

1 lb. of sea salt.

From this memoir it appears, that bleaching was now adopted in various parts of France, and that the chief obstacle to its being brought into general use was the want of a convenient and safe apparatus for the production of the oxymuriatic acid. This desideratum was accomplished by Berthollet, and it formed the main object of his memoir to explain very minutely the construction and principle of the apparatus he had contrived, together with the proportion of the materials for distillation, so as to render the practice of chemical bleaching general and efficacious. His directions are, to use

6 ounces of pulverized oxide of man

Soon after this period, some manufac turers at Javelle near Paris announced in several Journals, that they had discovered a particular liquor which they called the Lye of Javelle, having the property of gas-bleaching cloth by a few hours immersion. This composition, which was immediately analysed by Berthollet, was found to be nothing more than a solution of the oxymuriate of potash; and, on is attempting to prepare the solution, he unmediately perceived that the addition of the potash to the water caused it to imbibe the gas sooner, and that it likewise formed a more concentrated liquor..

12 ounces of sulphuric acid, and 12 ounces of water.

When the excellence of this process was thus established, he repeated the experiments in the presence of the celebrated - Mr Watt; and he adds, that soon afterwards Mr. Watt wrote him from England that he had applied his discovery, and in his first attempt had bleached 500 pieces of cloth in Mr. Mac Gregor's large bleach ground at Glasgow, and that this eminent manufacturer had determined to continue the process.

In the mean time, a M. Bonjour, who had been an assistant to Berthollet in his first experiments, connected himself with a M. Constant, a cloth finisher at Valenciennes, for the purpose of forming a bleaching establishment at that town; but, owing to the violent opposition of the neighbouring bleachers, they were unable to procure ground for the purpose on any reasonable terms.

In this difficulty, a patriotic French nobleman, the Count de Bellaing, who favoured the enterprize, and was made acquainted with the extent of the opposition, gave them possession of a piece of land at

The manufacturers of Javelle, before mentioned, having been disappointed in their commercial prospects at home, came over to England, and settled at Liverpool for the purpose of manufacturing the solution of oxy-muriate of potash, which they proposed to sell to the English bleachers in bottles, and which they still Jenominated the Liquor de Javelle.

[ocr errors]

These men, although they had been unable to introduce their article in France, so that it might have been consumed in sufficient quantities to answer their purpose, were so sanguine respecting the sale of it in England, that they applied to the British Parliament for an exclusive right to the invention, for the term of 28 years. Fortunately, however, one of the gentlemen who first applied the oxy-muriatic acid to the purposes of bleaching in this country, happening to be in the gallery of the House of Commons at the time the application was made in behalf of these foreigners, he took immediate measures to inform the principal members that this was not a new process; that he himself had long ago prepared an article equally efficacious, and that he would be ready to substantiate the truth of his statement when required. Their purpose was thus defeated, and the act was not obtained.

The peculiar advantages of combining the oxy-muriatic gas with lime or potash, consists in this circumstance, that the saline solution gives out its acid gradually to the goods which require bleaching, but does not give it out with facility to the at

mosphere. In consequence of this, the operation of bleaching is now not injurious, nor even disagreeable to the workmen ; whereas in the former process, when the

gas was merely received into water, it was given out again so freely that no man could long endure to work in it, or even for any considerable time to superintend the operation.

In addition to these advantages, the saving in interest of capital is incalculable, as will appear from one or two considera-sand

tions.

vise no one to make too free with them; especially, no one who has not an abundance of water at command. After all, bleached on the grass is exposed to vadamages are by comparison; for cloth rious misadventures; sometimes to its great injury.

We turn now to another subject, which demonstrates the advantage of chemical knowledge, more than a thou

theoretical arguments could do. We shall suffer Mr. P.'s history to tell its own tale, in the author's words.

In bleaching linen goods, in a great work, where one large parcel follows another, in regular succession, and through the different operations, five weeks is as much as is now ever allowed for the completion, and a small parcel can be begun and finished in a few days; whereas, by the old process, the effect could never be fully produced in less than eight months, as I have before mentioned.

Barytes is a heavy mineral, called ponderous spar, and many other names, found in large masses in the Derbyshire lead mines, in the Cornwall copper mines, &c. in a great variety of forms. The artificial sulphate of barytes is the permanent_white of painters in was ter colours. Barytes is usually found in the state of carbonate. Says Mr. P. speaking of the once famous lead mines of Anglezark, in Lancashire,

Moreover, the bleaching of linen was formerly very seldom accomplished with less than from S3 to 35 per cent. of waste, whereas the waste now, is not more than The quantity of carbonate of barytes in 26 or 27 per cent. This, of itself, is a pre- these mines is immense, much greater, I sumptive proof that the goods are less in-understand, than that of the lead ore jured, and evinces the superiority of the present practice.

five to one, as our guide supposed); but as the metallic ore was raised, this was always left behind in the mine, being considered of no value. The workmen called

it

Such are the principal points in the History of Bleaching: but, the reader is to conceive of many failures, and great damages done, before this system was perfected. We speak from experience; for, the same process being adopted at the paper mills; it was our lot to witness the destructive effects of this acid on several parcels of paper, out of which the corrosive principle had not been sufficiently washed: these, while dry, appeared fair to the eye; but, when wetted, the acid resumed its activity, and in a few weeks the paper cracked

and crumbled to rottenness.
We are
not quite free from suspicion that some-
what of the same kind occasionally
takes place in Domestic linen, which
good housewives affirm, with an expres-
sive gravity of countenance, does not
now last so long, or wear so well, as
formerly. At this we hinted, in our
considerations on the Report of the
Committee appointed to consider then
propriety of favouring the manufacturers
of Bleaching Salts: they may be ad-
vantageous oh the whole, under good

The papers in the Philosophical Transactions by Dr. Withering and Mr.Crawford on the carbonate of barytes had now

management; but, with Mr. P. we ad-drawn the attention of all the chemists of

spar.

Some of the best informed people in the town of Chorley say, that the first time any idea was given of the value of this spar, was by the arrival of two Frenchmen about twenty-eight years ago. It appears that they were in the town some days without the nature of their business being suspected, till it was at last discovered that they had been at the lead mines, and had filled two boxes with the spar, which they secured with great care, and sent off by the carrier before they left the town.

At this, Mr. Tatham, the steward of Sir Frank Standish, immediately took an alarm; and having given strict orders that in future no one should be suffered to take away any of the spar, set himself to make every inquiry he could into its nature; to learn, if possible, to what uses these foreigners intended putting it; and whether some methods might not be discovered for consuming it in this country.

prosecuting these objects of inquiry,

however, he never succeeded.

[ocr errors]

Europe to this newly discovered mineral; | ascertaining something more, if possible, so that its real nature and properties respecting this traffic in the Anglezark were every where soon understood. But spar; and from one Alexander Gerrard, during this investigation, in which every an intelligent farmer, who resides not far chemist who was fortunate enough to pro- from the mine, and was formerly very incure specimens was probably engaged, timate with the aforesaid James Smithels, nothing new occurred at the mine or in the I learnt the following particulars. neighbourhood, respecting it, till it was discovered that a man of the name of Smithels, who occupied a cottage and about forty acres of land under Sir Frank Standish, close to the mines, had long been engaged in disposing of the carbonate of barytes in an illicit manner.

|

This man, who was well known in the neighbourhood of Chorley, and is still remembered by many of its inhabitants, used to get the spar from among the heaps of stone and rubbish that lie round the mouths of the old shafts. This he used to pack in strong boxes, and delivered them himself, by his own cart, to the carrier in Chorley, to be conveyed to Liverpool.

He managed this business so well, that he not only bought the boards for making the boxes, but prepared the boxes himself in the night, and suffered no one to see him pack the article, or carry it away when packed. Besides, it went from Chorley by the common carrier to a bro-licking some lumps of spar, which at that ker in Liverpool, who shipped it to a middle-man upon the Continent;-so that the place where it was actually consumed could never be traced out.

sonous nature of this mineral, Mr. DerbyOn my affecting ignorance of the poishire assured me that some years ago, he lost three cows at one time, who had strayed from their pasture, and were found

and that on opening one of these animals, time lay about the mine in abundance; several small pieces of spar were found in its stomach.

"

A neighbouring farmer had, indeed, for some years observed that James Smithels was often engaged in picking something from off the waste land; and that often on moonshine nights, when they imagined no one observed them, he and his wife were employed for hours together upon the mounds which stand round the old shafts; and on the circumstance being mentioned to the steward of Sir Frank Standish, he put an entire stop to this poor man's little trade.

However, when he was questioned by the steward, and by a variety of other persons, respecting this transaction, he remained sullen and silent, and would never give them the least information as to the quantity he had sold, the price he obtained for it, or even to what part of the world it went. It was, however, imagined that the two foreigners before mentioned were the people who had engaged this man to collect it, and that they had found some means of regularly paying him for what he procured for them. As the quantity of carbonate of barytes thus collected, was much larger thau merely to serve as a chemical test and a few common purposes of philosophical research, I was desirous of

he died, informed Gerrard that, in the
That Smithels, only a short time before
whole, he had sold a very large quantity
of the spar; that he received five guineas
to some part of Germany; and that he
per ton for it; that it went from Liverpool
had understood, from the person who
usually paid him, that it was consumed in
celain.
some process in the manufacture of por

these poor uneducated men had any idea
Being desirous of knowing whether
of the nature and properties of the carbo-
nate of barytes, I put some questions to
them for that purpose. They told me,
strong poison.
all they knew of it was, that it was a

He told me also, that it was impossible to keep any fowl upon the farm; for, mistaking the smaller pieces of the spar for white sand, they were sure to pick it up, and die the first day they got out upon the land. Ducks and geese, he says, he can keep, as they do not swallow it, except at the time they lay their eggs, and then they never fail to take it, and with the same baneful effect. Doubtless they mistake it for lime or chalk, which all oviparous anitheir laying, in order to shell their eggs. mals are obliged to swallow at the time of

Hitherto, this singular mineral has been employed, chiefly, as a chemical test, and in the formation of certain salts. A few physicians have used it medically: we shall not say in what disorders, as the article is not only dangerous in itself, but some specimens of it contain copper, and others arsenic. Mr. P. suggests several useful purposes, as cements, &c. to which it may be applied.

A propos on Poisons: it may be well to bring our readers acquainted with the following remedy,

As the uses of sulphuric acid are become | ing, with which, our report on Mr. P.'s 10 various, cases may occur of its being volumes must conclude. taken into the stomach by mistake, and without immediate relief its corrosive properties would produce fatal effects. If magnesia should be at hand, that earth mixed with water and sweetened with sugar, would be the best possible antidote to the poison; but in case this could not be immediately procured, soap-water, which can be furnished by all families, and which is one of the next best remedies, should be drunk plentifully. The late unfortunate death of an infant son of the Hon. and Rev. E. Knox, at Dungarvon Park, in consequence of his swallowing a quantity of oil of vitriol which had been carelessly left on the table by a female domestic, shows how important it is for the public to be acquainted with the proper remedy in such cases.

We could have wished that Mr. P. had enlarged the number of domestic remedies for similar purposes: they would have formed a valuable and benevolent addition to his labours, and might have fixed themselves on the memory. He sometimes indeed, gives cautions to his unpracticed operators; but in our opinion excessive caution cannot be too strongly enforced. Even Panoramists have unwarily spirtled destructive concentrated gasses in their face and eyes: and have paid, for one single experiment, the cost of a new suit of clothes, when black satin waistcoats and breeches were in fashion.But, we must draw this article to a close. Our readers will perceive that we have perused the volumes with much interest, and satisfaction. If we do not think that Mr. P. has always hit the ancient history of articles to the greatest advantage, yet his references are fair, and without pedantry; their modern history is more to his purpose, and that of his purchasers. The work is valuable; and the public will not fail to profit by the hints dispersed throughout it.

England, is the only country for Black-lead pencils: we remember when the literati on the continent supposed them to be melted into the form in which they received them, and, conceiving this mineral to be an artificial production, they attempted to imitate it. By much the best account of the mine where it is found, that we have seen, is the follow

MINE AT BARROWDALE.

On a journey to the Lakes of Westmoreland and Cumberland, in the summer of the year 1814, I heard that the celebrated mine of black-lead in Barrowdale had been lately opened, and that the workmen were then engaged in raising and dressing the mineral. Rejoiced at this intelligence, I immediately determined not to lose so favourable an opportunity of visiting this curious spot, and therefore fixed myself at Keswick, the nearest town to the mine, in order to collect the necessary preliminary information, and learn how to procure the bourhood could afford. In traveling from most intelligent guide which the neighthe north, the road lies thus:-From Carlisle to Wigton is 11 miles; from thence to Keswick is 22 miles; and from Keswick to the mine 9 miles. It is necessary to take a chaise from Wigton to Keswick, as there is no mail or other coach which runs between those towns. From Keswick to the mine saddle-horses are necessary, as some of the defiles through the mountains are too narrow to admit the passing of a carriage. As no account has hitherto been given of this celebrated mine, where blacklead is found of a quality far superior to what is known in any other part of the world, I trust the following particulars will not be uninteresting to my readers.

The neighbourhood of Keswick has for ages been celebrated as a mining country. In the reign of Queen Elizabeth, gold and tity from the mountain called Gold-scarpe silver were procured in considerable quanin the vale of Newlands near Keswick. At that time the mine was worked by a company of Germans, who raised a large quantity of copper and lead, and not only converted these to their own use, but also laid claim to the precious metals, in opposition to the Queen, who demanded them as well as the usual royalty. However, on an appeal to common law, her majesty gained the point, and the foreigners soon

after absconded.

It was during this reign that the very valuable mine of black-lead, or plumbago, was first discovered at Barrowdale. The inhabitants of the neighbourhood say that this rich depository was first brought to light by a tremendous hurricane, which blew up a large ash-tree and discovered a mass of fine plumbago at its root. The mine now at work is in the midst of a mountain about 2000 feet high, which rises at an angle as near as I could guess of 45

[ocr errors]

degrees, and is situate among other stupendous hills in a district known by the name of Burrowdale. When the value of this mine became known, the proprietors found it very difficult to guard it so as to prevent depredations. The practice of robbing it was become so common, that several persons living in the neighbourhood were said to have made large fortunes by secreting and selling the mineral: this, however, is now entirely prevented by some expedients hereafter to be mentioned. Even a guard stationed on the spot was of little avail, for 70 or 80 years ago a body of miners broke into the mine by main force, and held the possession of it in spite of the proprietors themselves. At one time the depredations had arrived to such a pitch, and such vast quantities had been stolen, that the delinquents undersold the proprietors in the Loudon market, so that the latter found it expedient to buy up the remainder of their stock, in order to bring the price to its old level. It is not many years since a very large quantity of fine black-lead was found on Vickers Island, situated in Derwent-water, and it is supposed that this was secreted there at the time the robbers had possession of the mine in Barrowdale.

It has been already mentioned that the black-lead mountain has an altitude of about 2000 feet; and as that part of the mine which is now working is near the middle of the mountain, the present entrance is about 1000 feet from its summit. There are indeed two entrances; a small one by which the workmen descend by means of a flight of steps; the other is a large horizontal one capable of admitting hand carts and wheelbarrows for the removal of the rubbish and loose earth by which the black-lead is enveloped, and through this entrance the water passes off which constantly runs through the mine.

In order to secure the vast treasure which is contained within this mountain, the proprietors have now erected a strong brick building, consisting of four rooms on the ground floor, one of which is immediately over the opening by which the workmen enter the mine as they go to their work. This opening is secured by a trap door, and the room counected with it is called the dressing-room; for, when the men enter it, they strip off their usual clothes, and each of them puts on a dress suitable for working in a mine. The men work six hours each, and then they are relieved by others. When the hour of rehef comes, the steward attends in the dressing-room, to see the men undress, as they come up the steps one by one out of the mine, when

they put on their usual clothes, which are also examined by the steward to see that they have no black-lead concealed within them. This room contains no furniture except the pegs on which the clothes are hung ail round the room, each man knowing his own. When these have dressed and departed, another set of men clothe themselves for their work and enter the mine as before, when the trap-door is again shut, and the steward is relieved to attend his other occupations.

I have said that the house consists of four rooms, and these are contrived so that they conuect with each other. In the innermost of these rooms there is a kind of counter or strong table, under the window, at which two men sit; who are constantly employed in assorting and dressing the mineral. This is necessary, because it is usual to divide the black-lead into two kinds, called best and coarse; and as the finest specimens have generally pieces of iron-ore or other impurity attached to them, these are dressed off by peculiar tools adapted to the purpose. These men are constantly shut in when at work, and the steward walks backwards and forwards in an adjoining room furnished with two loaded blunderbusses, which hang within his reach, for the sake of further security. As the black-lead is cleaned, it is put into firm casks which hold about 112 lbs each, and these are sent by waggons to the warehouse of the proprietors in London. Formerly this mine was opened only once in six or seven years; but in consequence of the demand being greater, and the quantity which they have discovered not being so large, it has been found expedient to open it and dig for ore during six or seven weeks every year. During this time the mine is guarded night and day; and it is thought necessary that the steward who lives only at the village of Seathwart, at the foot of the mountain, should not leave the house night or day during the whole of this period, except an hour or two on the Sunday to visit his family, and even then, as he told me, he was alwayı careful to return to his dwelling on the mountain while it was yet light. Tu consequence of the mine having of late years been opened every summer, they now raise all the black-lead they find, and then the mine is securely shut up in the following manner :-The workmen wheel back the rubbish which had been removed at the opening of the mine, and this is laid in one continued heap, to the amount of some hundred cart loads, which securely blocks up both passages into the mine. The door is then locked, as well as the

« AnteriorContinua »