MUR

MUR

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The brine fprings in this country feldomcontain more than one per cent, of fait in thenatural ftate, but by mere graduation the brineis brought as high as 20 per cent, after whichit is ready to be boiled down as ufual. Toeffeft this concentration therefore, 20 parts ofbrine mull part with 19 by evaporation throughthe faggots. The depofition of ftala&ite hard-ly begins till the brine is brought to 5 percent, of fait, and it ceafes altogether wlxen itis brought to 15 per cent. The graduation ofthe brine becomes flower as the concentrationincreafes. With regard to the a£tual effeft ofa given quantity of faggots, Haller finds thatat a mean degree of concentration or 10 percent, the evaporation of a Angle day in Swit-zerland , taking the average of the entire year,is 1100 cubic feet, (reckoning the weight ofthe cubic foot at 46 lb. of 18 oz.) in a row offaggots 20 feet high, and 735 long. Whenthe fun fhines ftrongly, the exhalation is morethan double the above quantity.

A graduating houfe of the above dimenfionsis eftimated to have always at work about1,912,000 lbs. of brine, and this quantity isfurnifhed eleven times in the year to the boilingpans. There appear to be two inconveniencesin graduation, one, which is but trifling is, thatthe brine extracts at firft fome colouring matterfrom the faggots, which is never totally got ridof in the fubfequent evaporation, fo that thefait has a little brownifti tinge. The other ismore ferious, and it is the afifual lofs of brineby graduation either when the wind is too vio-lent, or the procefs managed unfkilfully andthe faggots not well arranged. This in fomefait works is eftimated as high as from 30 to40 per cent.

Klaproth has fome valuable experiments ongraduated brines in his analyfis of the faitfprings of Konigfbom, which is a fait moun-tain extending from Paderborn to the Dutchyof Cleves, and into the bifhoprick of Munfter.The brine is found much ftronger the deeperit is drawn. That obtained at 50 feet from thefurface contains only 11 to 2 per cent of fait,at 80 feet it is 2|; and at 120 feet it rifes to31 or per cent.

The method purfued by this excellent chemiftin the analyfis of the brine, may be alfo fhortlymentioned as a direction to the reader whomay with to repeat the experiments.

1. Fifty cubic inches of brine (each equalto 290 grs. of diftilled water) were evaporated

to drynefs in a fand heat, and the weight noted.

2. The refidue was covered with alcohol anddigefted in a moderate heat for 24 hours.

3. The alcoholic folution was poured off andevaporated to drynefs, and frelh alcohol pouredon the refidue in order to rediflolve all the fait*except the fmall portion of common fait whichthe firft alcohol had taken up. The laft al-coholic folution was then evaporated to drynefsand the refidue weighed.

4. The dry refidue from the laft alcoholicfolution confifted of muriat of lime and muriatof magnefia, and the weight of each wasdetermined in the following manner: the refiduewas difl'olved in water, and the earth precipi-tated by carbonat of foda. This earth, wellwallied, was then combined with fulphuric acidto excefs, and after the mixture had ftood awhile in a warm place, the excefs of acid wasabforbed by adding carbonat of lime. Thefolution was then evaporated confiderably (re-moving the fulphat of lime as it was formed)and then expofed to exhalation in the open air,whereby the fulphat of magnefia was feparatedin cryftals. Thefe laft were collefted, re-difiolved in water, decompofed by foda, andthe magnefia faturated with muriatic acid andevaporated to drynefs. It was then pure muriatof magnefia brought to the ftate in which itexifted in the dry refidue of the brine, and theweight of the muriated lime originally mixedwith it was found by fubtrafting the weight ofthe muriat of the magnefia from that of theentire alcoholic refidue.

5. The dry fait remaining after the feparationof thefe earthy muriats was then difl'olved inwater and filtered.

6. What was left on the filter confifted offulphat and carbonat of lime, and exyd of iron.When weighed, it was treated with muriaticacid, and the fulphat of lime left on the filter.Ammonia was added to feparate the iron whichwas collefted and weighed.

7. The clear folution of No. 5 might ftillcontain fulphat of lime; it was therefore boiledwith carbonated foda, when a carbonated limefell down. The foda added was then neutra-lized by muriatic acid, and muriat of barytesadded, which gave a precipitate of fulphatof barytes, {hewing therefore the exiftence offulphuric acid in the brine, which muft havebeen combined with the lime obtained by thefoda. The quantity of fulphat of lime wasinferred from the united weights of the car-

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