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all that is between the edge of the knife and the verge of the anus.' The operation being performed, a soft dofil of fine lint must be introduced between the lips of the wound, and the rest of the sore drest with the same,

Whoever compares this simple operation with those in similar cases of former times in this kingdom, and even of the present age in other countries, will immediately be convinced of the value of this treatise. The latter part of the work is chiefly employed in demonstrating the absurdity of the usual method of treating this disorder, particularly in France, in which the Author reasons candidly, judiciously, and, we think, convincingly to unprejudiced readers.

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An Efay on British Ijinglafs: Wherein its Nature and Properties are

compared with the foreign Sorts; with the best Methods of converting them into Fining, Glue, and Starch, for the Use of the Brewer, Vintner, Paper-stainer, &c. comprehending a succinat Analysis of lfinglass, and Rationale of its Action in clarifying Lia quors. Interspersed with Hints for the further improving of Malting, Brewing, Fermenting, and for preventing the Waden Apparatus in the Brewery froni speedy' Decay. By H. Jackfon. 8vo. 1 s. 6d. Newbery.

HE home-manufacture of an article which is imported at

an exorbitant price, and forms a disadvantageous balance in the way of commerce, is a subject of great importance ; and the inventor of a method by which we may be supplied with such article from our own labour and our own materials, is entitled to the countenance and patronage of the legislature.—The preparation of Ifinglass hath been long kept a secret by the Russians. Neuman, indeed, and others, have given a description of the fish from which this particular species of glue is extracted, and a fort of bearfay account of the process by which it is made: the Russians, however, were the first inventors of this art, have continued to be the sole manufacturers, and from them all Europe bas been supplied.

In Mr. Jackson's effay we meet with the following interesting particulars :- that the art of making Isinglass in England from British materials, after a moft rigid scrutiny into its merits, has been adjudged a new and useful invention ; that several tons weight of this manufacture have been consumed and inconteftibly proved in a court of judicature, to answer the purposes of the toreign; and that all sorts of Ifinglass may be manufactured at home, as soon as we receive a due supply of materials from our

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American provinces, the rivers of which are well known to abound with an inexhaustible plenty and variety of fish, that will yield fine Isinglass fufficient for the consumption of all Europe, provided a just encouragement be given to our fisheries.That our Author's intent in the present publication was to set the subject of British Isinglass in its true light, and to communicate a method whereby the most perfect fining for the purpose of clarifying malt liquors may be made from the same, equal in efficacy to that made from any sort of foreign lsinglass whatever; that the coarser forts, if perfectly dry and sound, are not inferior to the best staple-isinglass, for the uses of the brewer ; they require only a longer time, and a proper management, to le formed into fining: that from some very accurate experiments, made by a gentleman of undoubted honour and veracity, it appears, that fining made with British Isinglass performs its office more speedily, and falls closer to the bottom, than the foreign ; that the fine, pellucid sorts, are consuined in making mockpearls, and in stiffening linens, filks, gauzes, &c. the use of gums and starch being juftly laid afide, on account of their dirposing the fabrics to rot, crack, and mildew ; that the inferior forts have been reduced two hundred per cent. since the commencement of the British manufacture; that for this article there is an annual remittance of forty thousand pounds sterling ; that the yearly consumption in the brewery is calculated at twentyfive tons; that one in four has been saved by the home manufacture, and that by an adequate supply of materials from our own colonies, this importation may be entirely superseded.

If the above particulars are justly represented, we hope Mr. Jackson will reap the fruits of his application and invention. We think, however, it would have been more to his reputation, if, in one part, he had not appeared a little in the character of a noftrum-monger. The virtues of Isinglass for the purpose of fining are much injured, if, by being exposed to beat, its difolution is urged beyond a certain point: and this disposition to liquify is more remarkable in British than foreign lfinglass. • The whites of eggs, says Mr. Jackson, well whisked up, and commixed with British fining, greatly prevents its fuidity, and acts very powerfully in the business of fining ; but as that addition is generally too costly for this purpose, we hope to be able to discover fome cheap substitute to answer the same intentions. As this must be the result of experience, we shall be filent in this point, at present, except that it may not be improper to hint, that there is a certain faline matter easily procurable, which, if commixed to the proportion of a dram to a barrel of fining, greatly improves its clarifying principles, the rationale of which thall be mentioned hereafter. Poffibly our Author may have been provoked to this piece of secrecy by the prejudice and inviFf 2

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dious censures of his enemies ; and of which he more than once complains.—So firmly, says he, is this bigotry established, that I have lacely been allured by unexceptionable évidence, that a certain saponaceous * brewer persists to deny the practicability of making lsingiass in England, and represenis the affair as an infidious trick to impose upon those less happy in discernment than himself; this circumstance reminds me of a story fathered upon a certain Welchman, who, cn his arrival at London, mistaking British asparagus for lecks, began to devour the wrong ends; and, notwithstanding he was frequently admonished of his error, yet, rather than acknowledge it, continued to eat it so all his life-time.'

Our Author supposes that the fining powers of Isinglass depend upon its fibrous texture. These fibres are easily rendered visible to the naked eye ; and are fitted for their operation by being separated, macerated, or in pait dissolved by a proper medium.Neither gum, fize, glue, jellies, which are a kind of half-finished glue, or Iringlass itself diffolved in hot water, poslels the fining properties of lsinglass when duly divided by a subacid menftruum; and the best menitruum for this purpose is frong fale beer.That any person may have an opportunity of observing the operation of fining, or be satisfied as to the relative merits of British or foreign Isinglass, Mr. Jackson directs the following experiments.

• Provide a cylindrical glass, about five inches diameter, and two feet long, which may be easily procured at the glass-houses; let it be made pretty strong, with a narrow rim, that it may

be laid over with a cover occasionally, and likewise have a glass cover fitted to it, like what the confectioners use. Let a small whisk be prepared, by stripping off as many sender twigs from a birch broom, or common whisk, as will give it the thickness of half an inch in the middle, where it is to be tied round with pack-thread ; draw off as much beer out of the butt intended to be fined, as will fill the glafs within four inches of the top, then beat up about fix spoonfuls of fining in a bason, with the whisk, una few minutes by itself; after which add gradually a little of the beer in the glass, and whilk it again till it appears very light and frothy : ftir the beer about briskly in the glass, and immediately pour in te firing, and commix them very well, put on the cover, and place the glass in a good light; as soon as the mixture has lost its vertical motion given it by stirring, innumerable little mafies, resembling brown-coloured curd, may be perceived to form and move in various directions throughout the whole liquor, which every moment increafe in magnitude, till at length they feparate at considerable distances, and some parts fall down

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to the bottom, while others ascend to the top, on account of some air bubbles, confined in the curdled matter, which, on breaking at the surface, fall directly to the bottom; but if the air is not discharged, the curd will be suspended thereby, and form a kind of scum ; if the fining is good, and the beer in proper condition to receive it, that part in the middle of the glass will become of a blackish transparent hue in a short time, and if prudently drawn off by a syphon, will be found very bright; in twenty-four hours the fining will settle pretty close to the bottom, and very little remain at top, unless the beer be in a fretting ftate; in which case the fining will be carried tumultuously up to the surface, by means of the vast number of air bubbles perpetually generating and ascending in all fermenting fluids; but as soon as that action is over, the fining will fall to the bottom, and produce its proper effect, especially if a sinall addition be Nightly stirred in at the surface the next day, with caution not to disturb what is already subsided; thus it is evident, that at the very inftant that fining is commixed with beer to be clarified, the stale beer, in which the Ifinglass was diffolved, or divided, quits the fibres, and unites with the body of the beer ; while at the same time the fibres, now set loose, and every where interspersed in the beer, attract and unite with the loose feculent particles, which, before this union, being of the same specific gravity with the beer, could not possibly subside alone, but by this reciprocal attraction having obtained an additional weight, are now rendered proportionably heavier, and precipitate together of course in form of the curdly magma just mentioned.'

The above phenomena, we apprehend, are not to be explained from any mechanical consideration of the fibrous texture of Ifin-, glass, but manifestly point out what the chemifts call an ELECTIVE ATTRACTION,

Where the beer is specifically heavier than the fining, the fining rises and Aoats at the surface, fays our Author: but where the beer and the fining are of the same specific gravity, they remain united, the feculencies do not subside, and the beer is then said to be stubborn.Stubbornness, however, we imagine, does not so much depend upon a sameness as to the specific gravities, as upon some fault either in the beer or the fining, by which the elective attraction is prevented taking place. When beer is stubborn, Mr. Jackson recommends a particular attention to experiments made with his proof-glasses: these, he says, are made of the best glass, and contain about two quarts each, wih a mouth about one inch and half, and bottom three inches diameter ; their form is pyramidal, the better to prevent the friz from adhering to the sides, and examine the colour of terwca different densities,

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· Thus, if we want to know the condition of different guyles or butts of beer, a glass must be appointed to every butt, which must be marked or numbered; each glass must be filled two thirds full, or more, with the respective beers placed in a good light, and the taste, colour, and fretting dispofition first examined i then having a little good fining ready whisked up in a bason, as before directed, put into each glass a common spoonful by measure, with the usual precautions ; 'twist a little paper over each g'ass, and let them stand quiet; in a short time a person of tolerable discernment will perceive what beer, according to the common phrase, falls kindly, or turns out stubborn, proves cloudy or fretting, high or low coloured, &c. he will likewise perceive what quantity of fining is necessary for one fort more than another, the difference of time in becoming bright, and furnish himselt with the most eligible methods of redrcfling general defects, and thus, by experiments in the small way, he will be enabled to form right prognostics, and may safely proceed to thç Jarge ; for whatever phænomena occur io the glass, will turn out exacily the same in the butt, due regard being had to difference in proportion.'-- Our Author would have performed a very acceptable service to the brewer, had he pointed out the pariiçular means and nianagement, necessary to remedy each particular fault

Mr. Jackson has precluded' any observations on his language or manner of philofophifing.– The presling solicitations, says he, of some friends, and the urgent necessity of publication at this juncture, I fiatter myself, will apologize for some inaccu. sacies, &c.'-We cannot enter into any detail of our Author's hints on malting, brewing, fermenting, &c. but recommend his elray to the perusal of those who are interest¢d in these subjects.

D.

Conclusion of the Account of Moheim's Ecclefiaftical History. See

our Review for October, p. 330.

HO

'AVING, in two preceeding articles, endeavoured to give

some idea of the first volume of this excellent work, we lhall now conclude our account of it, by laying before our Readers some extracts from the second volume, which is introduced with a history of the Reformation. This vistory is divided into four parts: the first contains an account of the state of Christianity before the commencement of the Reformation; the second comprehends the history of the Reformation from its first beginnings until the daic of the confession drawn up at Augsburg; the third exhibits

a view

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