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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 doffil of fine lint must be introduced between the lips of the wound, and the rest of the fore drest with the fame.

Whoever compares this fimple operation with those in fimilar 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 abfurdity of the usual method of treating this disorder, particularly in France, in which the Author reasons candidly, judicioufly, and, we think, convincingly to unprejudiced readers.

An Epany on British Isinglass: Werein its Nature and Properties are

compared with the foreign Sorts; with the bent Methods of comqurting them into Fining, Glue, and Starch, for the Use of the Brewer, Vintner, Paper-stainer, gr. comprehending a fucina Analysis of lsingloss, and Nationale of its Allion in clarifying Liexors. frier/perfid with Hints for the further improving of Maiting, Bretvirs, Fermeriting, and for préventing the Wooden Apparatus in the Brewery fro:n speedy Decay. By H. Jackson. 8vo. 15. 6d. Newbery.

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'HE home-manufacture of an article which is imported at

an exorbitafit 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 fuck article from our own labour and our own materials, is entitled to the countenance and patronage of the legißature. The preparation of Isinglafs hath been long kept a seciet by the Ruffians. Neuman, indeed, and others, have given a description of the fit from which this particular species of glue is extracted, and a fort of hearsay account of the proces by which it is made: the Ruffians, however, were the first inventors of this art, have continued to be the sole manufacturers, and from them all Exrope has been supplied.

In Mr. Jackson's essay we meet with the following interesting particulars :- that the art of making Isinglafs in England from Britih materials, after a moft rigid fcrutiny into its merits, has been adjudged a new and useful invention ; that several tons weiht of this manufacture have been confumed and inconteftible p.oved in a court of judicature, to answer the purposes of the foreign; and that all sorts of Ifinclass may be manufactured at hyme, as soon as we receive a duc fupply 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 fith, that will yield fine Ifinglafs fufficient for the confumption of all Europe, provided a just encouragement be given to our fitheries. That our Author's intent in the present publication was to set the subject of British Ilinglass in its true light, and to communicate a method whereby the most perfect fining for the purpote of clarifying malt liquors may be made from the same, equal in efficacy to that made from any sort of foreign lfinglass whatever; that the coarfer forts, if perfectly dry and found, are not inferior to the belt Napie-ifinglass, 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 Ifinglass performs its office more speedily, and falls closer to the bottom, than the foreign; that the fine, pellucid forts, are consumed in making mockpearls, and in ftiffening linens, filks, gauzes, &c. the use of gums and starch being juftiy laid aside, on account of their disa paling the fabrics to rot, crack, and mildew ; that the inferior forts have been reduced two hundred per cent. since the cammencement of the Britth manufacture; that for this article there is an annual remittance of forty thousand pounds tterling ; that the yearly consumption' in the brewery is calculated at twentyfive tons ; that one in four has been saved by the home mandfacture; and that by an adequate supply of materials from our own colonies, this importation may be entirely superseded.

If the above particulars are juftly represented, we hope Mr. Jackson will scap 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-mmger. The vistues of lfinglass for the purpose of fining are much injured, if, by being exposed to beat, its diffolution is urged beyond a certain point: and this disposition to liquify is more remarkable in Britith than foreign Isinglals. • The whites of eggs, says Mr. Jacklon, well whisked up, and comm with British fining, greatly prevents its Huidity, and acts very powerfully in the business of fining; but as that adLition is general,y too costly for this purpose, we hope to be able . to discover fome cheap subititute 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 imp:cper to hint, tbat there is a certain faline matter easily procurable, which, if caminixed to the proportion of a dram to a barrel of fining, greatly improves its ciarifying principles, the rationale of which Ihall be mentioned hereafter.? -Possibly our Author may have been provoked to this piece of fecrecy 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 lately been assured by unexceptionable evidence, that a certain faponaceous * brewer perfifts to deny the practicability of making Isinglass in England, and represents 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, on his arrival at London, miltaking British asparagus for leeks, 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 lupposes that the fining powers of Isinglass depend apon its fibrous texture. Thele fibres are easily rendered vifible to the naked eye ; and are fitted for their operation by being separated, macerated, or in part dissolved by a proper medium.Neither gum, size, glue, jellies, which are a kind of half-finished glue, or Ifugiass ittelf diffolved in hot water, possess the fining properties of lfinglass when duly divided by a subacid menftruum; and the best menftruum for this purpose is strong 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 er foreign Ilinglass, 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 slender twigs from a 'birch broom, or common whilk, as will give it the thickness of half an inch in the middle, where it is to be tied round with pack-thread; draw ott as much beer out of the butt intended to be fined, as will fill the glass within four inches of the top, then beat up about fix spoonfuls of fining in a bafon, with the whisk, a few minutes by ittelf; after which add gradually a little of the beer in the glass, and whisk it again till it appears very light and frothy: ftir the beer about briskly in the glass, and immediately pour in the fining, 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 increase in magnitude, till at length they separate at confiderable distances, and some parts fall dowi

Mr. Combrune defines kort to be a species of soap.

to the bottom, while others ascend to the top, on account of fome 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 small addition be fightly 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 ftale beer, in which the Ifinglass was dissolved, 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 Ilinglass, but manifestly point out what the chemists. call an ElecTIVE ATTRACTION.

Where the beer is specifically heavier than the fining, the fining rises and Aoats at the surface, says our Author: but where the beer and the fining are of the same specific gravity, they remain united, the feculencies do not fubfide, 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 ex. periments made with his proof-glasses : thcse, he says, are made of the best glass, and contain about two quarts each, with a mouth about one inch and half, and bottom three inches dia. meter ; their form is pyramidal, the better to prevent the fining from adhering to the sides, and examine the colour of beer under ifferent densities,

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Thus,

• 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 tafte, colour, and fretting difpofition first examined; then having a little good fining ready whisked up in a baron, as before directed, put into cach 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 perfi:n of tolerable discernment will perceive what beer, according to the common phrase, falls kindly, or turns out fubtorn, proves cloudy or fretting, high or low coloured, &c. he will likewise perceive what quantity of fining is neceffary for one fort more than another, the difference of time in becoming bright, and furnish himfelf with the most eligible methods of redrefing general defecis; and thus, by experiments in the small way, he will be enabled to form right prognostics, and may safely proceed to the Jarge ; for whatever phænomena occur in the glass, will turn out exactly the same in the butt, due regard being had to difference in proportion.'--Our Author would bave performed a very acceptable fervice to the brewer, had he pointed out the pariicular means and management, necessary to remedy each particular fault.

Mr. Jackson has precluded any observations on his language or manner of philosophising.--" The prefing solicitations, says he, of some friends, and the urgent neceflity of publication at this juncture, I Aatter myself, will apologize for fome inaccuracies, &c.'-We cannot enter into any detail of our Author's hints on malting, brewing, fermenting, &c. but recommend his essay to the perusal of those who are interested in these subjects.

Conclusion of the Account of Mifheini's Ecclefiaftical History. Seç

our Review for Oaober, p. 330.

H

TAVING, in two preceeding articles, endeavoured to give

some idea of the first volume of this excellent work, we fhal! now conclude our account of it, by laying before our Readers fome extrads from the fecond volume, which is introduced with a history of the Reformation. This history 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 datę of thể confesion drawn up at Augsburg; the third exhibits

a view

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