Page:Cyclopaedia, Chambers - Volume 2.djvu/668

 SAL

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SAL

therefore acl: with lefs Violence than thofe of the Firft Clais of Salts. Acids joined to Fixed Salts, compoie Mixed Sails. Thus Spirit of Nitre-, with Salt of 'Tartar, make Salt-petre $ and Spirit of Salt, with Salt of Tartar* make a true Common Salt, and Spirit of Vitriol, with tffeft ofTartar, a true Vitriol. However, the two ingre- dient Salts ftill remain, the one Fixed., the other Vola- tile- Acids joined with Urinous Salts, compoie another Kind or iWtfj called ^Kfes Ammoniaci, which are always Volatile.

Lixivial and Urinous Salts, are called Mealies $ the firft a 2%m4 Alcali, the lecond a Volatile Alcali. Thefe ■lltalks are ulually efteemed Antagonifts to the yfo',^ &gj£5 becaule their Mixture always occasions a fudden Ebullition. But 'tis more probable this Ebullition is not the Effecl: of a Combat, but rather a proper junction and Union of" two Matters which had been naturally united together, and only leparated by the Fire, and now re-place themfelves in the lame Parts whence the Flame had tore them off. Hence, the one are compared to Sheaths, and the other to Points fit to be fheathed therein. Now, the Precipitation wherewith the Points of the Adds enter the Pores of the Alkalies, tears afunder their Contexture, and reduces them into minute Parts invisible to the Eye j and thus is the Bufmeis of Dijfolution accounted for. See Dissolution.

Thus far will the mere Doctrine or Alkali and Acid po towards accounting for ibme of the great Phenomena of Nature. But the Theory is made vaftly more com- pleat and adequate, by Sir Ifaac Newtm's Principle of Attraction., for which we refer the Reader to the Articles Acid, Menstruum, Sic. where the Operation of Salts, or Acid Spirits, are perhaps more fatisfaftorily accounted for.

The Principal Cbymical Salts of Ufe in Medicine are ; Salt of Urine, of Lavandcr, of Viper, of Human Shod, ot Wormwood, of Guayac, of Quinquina, of Tobacco, of Rhubarb, of Rofemary, of Calaureum, of Sage, of Ju- mper, of Vitriol, of Amber, of Saturn, &c. molt of which, with many others, are explained under the Arti- cles of the reipe&ive Drugs, £$c. whence they are drawn; To which the Reader may have recourfe.

Salt, in the popular Ufe of the Word, is ufed for a Kind of .y^/we Crystallization ; or a fharp, pungent, de- tergent and astringent Substance, ufed to Seafbn Flefli, Fim, Butter, Hides, and other Things that are to be kept: As alio to give a Relifh to Meats, &c. This Salt we ulu- ally call Commons-Salt, in Contra-diftinclion to the Cby- mical Salt. M. Guglielmeni, in an exprefs DifTertation de Salibus, lays it down as a Fundamental, that the fir It Principles of Common-Salt, Salt-petre, Vitriol, &c. have their Figures unalterably fixed at their firft Creation, and are indivisible as to- any created Force. That of Common- Salt, he maintains to be a little Cube 3 that of Salt of Vitriol, a Parallelipiped $ that of Salt-petre a Prifm, whole Bale is an equilateral Triangle, &c. Common-Salt is of three Kinds, viz* Sea-Salt, Foffile, or Rock-Salt, and Salt drawn out of Salt Springs and Wells.

For Sea-Salt, the greatest and beft Part is made in France -j little in England. Foffile, or Rock-Salts, are' chiefly found in (Poland, Hungary, and Catalonia. For Salt Fountains, they are considerable in Cbepire, Wor- cejlerpire, Hamppire, Northumberland, Franche Comte, Lorrain, Tirol, and fome other Places.

The Ufe of Salt is fo univerfal, and the Commerce thereof fo very confiderable in the Places where Nature has produced the different Salts, and fo neceflary for thofe which have not that Advantage 5 that a Detail of the Preparation, Commerce, f£c t of the feveral Kinds, cannot fail of being acceptable.

Manner of Making Sea*Salt.

This Salt is made of Sea Water, thicVenM by frequent Evaporations, and at length Crystallized. Of Sea-Salt there are two Kinds : That which requires the Sun's Rays to give it its Consistence, called, from its brown Colour, Say- Salt : And that which receives its Consilience from the Heat of a Fire, called White Salt. They ufe either this or that Manner of Preparation, according to the Difpofition of the Coafts, where 'tis made. If the Coasts rife in Downs or Hills of Sand, the Salt is made by Fire, in Copper or Leaden Veffels. It the Coasts be flat, and low ; efpecially, if the Bottom be a little Clayey, the Salt is Crystallized wholly by the Action of the Sun. We have nothing very confiderable of either Kind in BgZftA Some indeed we have of the latter, at Shields hi Northumberland', and of the former in the Hie of May. France is the principal Place for thefe Salts 5 more being made there than in all Europe, perhaps in all the World beside, and 'tis hence that we are chiefly furnifhed therewith. We {hall therefore deliver the Method of waking it, as it it praftifed there. The chief Coafts for

Say Salt are thofe of Sretagne, Saintonge, and the (Pays d' Aunis. The chief Salt- Works, in the two latter Places, are Srouage^ Maran, and the Ifle of Rhe. ThOie in Sretagne are in the Bay of Sorneuf, Guerand, and Crcijll: For White-Salt is chiefly made on the Coafts of Normandy. In the Bay of Sorneuf alone, are computed above Twenty Thouiand confiderable Sa.UWcrks.

Manner of Making Bay-Salt.

Low Mar/hy Grounds, difpofed by Nature for the Re- ception of the Sea -waters when the Tide f wells, and provided with Banks and Sluices to retain the fame, are called a Salt-marft.'Thclh Salr-?narjhes, the Bottoms where- of they ram with a deal of Care, are divided into feveral fquare Pits or Baibns, fome greater, others lets, leparated by little Dikes 13 or 14 Inches broad : And into thefe Batons, when the Sea I on is at hand, they let in the Sea- water. The Salt Seafon is from the Middle of May to the End of Jhmtjb 5 in which Time the Days being long, and the Sun's Rays strongest, the Salt is railed and cry. ftallized better than in any other Seafbn. E'er they let in the Water, they take Care the Baibns be well cleared of what had been left in them during the Winter to keep, them in Order. The Water is admitted to the Heigh th of about fix Inches, after having firlt let it reft, and warm two or three Days in huge Refervoirs, without the Works; that it may come in luke-warm. The Water admitted, the Sluices are ihut, and the reft of the Work left to the Wind and the Sun.

The Surface of the Water being {truck, and agitated by the direct Rays of the Luminary, thickens, at fitft,' imperceptibly, and becomes, at length, cover 'd over with a night Crutt, which hardening by the Continuance of the Heat, is wholly converted into Salt. The Water, in this Condition, is fo hot, that the Hand can't be pur into it without burning it. When the Salt has received its full Coftion, they break it with a Pole, upon which it finks to the Bottom, whence being dragg'd out again, they leave it tbmetimes in little Heaps, about the Edge of the Pit, to compleat the Drying - 7 and at length in greater Heaps, containing feveral Thoufand Muids, which they cover over with Straw, or Rufh.es, to fecure them from the Rain.

Eight, Ten, or at molt Fifteen Days, having thus per- fected the Crystallization of the Salt, they open the Sluices, when the Tide is riling, for a frefh Stock of Water 5 and thus they continue alternately, taking in Water, and gathering the Salt, till the Seafbn be over. Rainy Weather is very pernicious to the Work ; for Rain Water, mixing in any Quantity with the Sea Water, renders it ufelels, fo that new Water mull be called in. The Salt is brown when taken out of the Pits, and is ufually thus fold, without farther Preparation. Indeed inf fome Places they make it into White-Salt by refining. They refine it by boiling it in large flat Caldrons, whicht not only takes away its Acrimony, but is found to in- creafe the Quantity.

Method of Making White Sea-Salt.

l*he White-Salt of Normandy is not made by refining the Say-Salt, but has this Colour naturally when taken out of the Pits. To make it, they gather a muddy Sand on the Flats of the Shoar, which the riling Tide has" covered and impregnated with its Waters for feven or eight Days. This Sand being removed into Pits for the Purpofc, difcharges itfelf by degrees of all its Water, which filtrates through fome Straw wherewith the Bottom: of the Pit is filled, and trickles into Veffels fet on pur- pofe to receive it. Of this Water it is that they make their Salt.

Their Furnaces are of Earth, and their Boilers of Leads Each Furnace boils four Leads. When the Water where- with they have filled the Leads begins to boil, they take off the Skhrj, which arifes in abundance, snd in Propor- tion as it dim i nifh.es, throw in frefh Water, which they continue to skim, as before. When it thickens, they keep it continually ftirring, with a crooked Stick, o" Ladle ; and when the Grain is form'd, take it off the Fire to purify it.

The Purifying is performed by letting it frand in large Osier Baskets 5 where it drains itfelf of certain Humidi- ties that remained. When dry, it is laid in Heaps, and thence carried into the Magazines. The Commerce of White-Salt brings an immenfe Profit to France, though more to the King than to the Makers and Sellers : The Duty is one Fourth Part of the Price the Salt is fold at. The English atad 'Dutch, and (when they are at War with France) the Swedes and Danes, take oft' most of the Salts of the Compte Navtois ; paying for it, communihus AnniS) from 20 to %$ Livres the Load, That of Gue- [D'] fanM