MUR

( 122

)

MUR

bonat of fime and the fulphat of barytes, andfrom the quantity of the latter alfo it was provedthat no other fulphat exifted than that of lime.The fame was alfo fhewn by the gradual folu-tion of the, fait in a mixture of two parts ofalcohol and one of water, for the fulphats will.not fenfibly diffol.ve in this mixture withoutheat.

To {hew the precife effect of graduation wefhall now give Klaproth ’s analyfis of brine firftin its . natural ftate, and then through thefucceffive ftages of concentration in the gradu-ating houfe.

The natural brine was as follows: the fpecificgravity 1.024:

The entire refidue from 50 cubic inchesweighed 521 grs. which was compofed asfollows:

Muriat of lime - - -

- ' ^0 grains

- Magnefia - -

1

z

Carbonated lime - -

- IX

Carbonated oxyd of iron

r

“ z

Sulphat of lime - -

- u

Muriat of Soda - - -

- 464

521

This brine was brought by the firft gradua-tion to the fpecific gravity of 1.060. Therefidue from 50 cubic inches now weighed1285 grains, and confided of

Muriat of lime ------ 65 grs.

-Magnefia - - - - iy

Carbonated lime with a little iron 4|Sulphat of lime ----- 44

Muriat of Soda - - - - -1170

1285

The fecond graduation brought the fpecificgravity to 1.076, and the refidue to 1615 grs.which was compofed of

Muriat of lime - - - 75 grains

-Magnefia - - 2

Carbonat of lime - - 3

Sulphat of lime - - 48.

Muriat of foda - - - 1487

1615

The third graduation gave a fpecific gravityof 1.086 and a refidue of 1850 grains com-pofed of

Muriat of lime

- - 82 grain*

-Magnefia

- - 3

Carbonate of lime

- - 3

Sulphat of lime

- - 52

Muriat of foda

1710

1850

By comparing the above analyfes we mayinfer what muft be the effedf in graduation bothin concentrating the brine and in freeing it froma part of its impurities, and what muft be thecompofition of the ftalasftitical incruftation onthe faggots of the graduating houfe. It wouldhave been more accurate if the fucceffive changesproduced in an individual brine had been noted,but in the fait-works here mentioned thereappear to be a number of fprings all {lightlydiffering from each other in the proportion ofingredients, the brine of which is mingledtogether before graduation. On the wholehowever it is obvious that the great lofs of theingredients of the brine is in the carbonat oflime, for fince the entire refidue of a givenquantity of the rough brine amounts to only521 grains, and the refidue of brine thrice gra-duated is 1850 grains, the proportion of eachingredient (were there no lofsj fhould be ref-pedtively upwards of 3 { times as much in thegraduated as in the rough brine. Thus thequantity of carbonat of lime fhould in thegraduated brine be about 39 grains, whereasit is a&ually only 3. This lofs of carbonat oflime therefore fhould be found in the incrufta-tion of the graduating faggots, and accordinglythis is the cafe; for by analyfis 960 grains ofthis cruft contains no lefs than 828 of carbonatof lime. The exadl analyfis of this fubftanceis as follows:

Impure common fait - - 4 grains

Sulphat of lime - - - 25

Carbonated oxyd of iron - 92

Carbonated lime - - - 828

Moifture - - - - _ 11

960

The carbonated oxyd of iron alfo difappearsfrom the brine during graduation, and is foundin the incruftation.

When the brine is boiled down, what remainsof the carbonat of hme in it is precipitatedalong with felenite and common fait, and formsthat hard cruft which adheres fo firmly to thepan, and has been defcribed already under, thsterm pickings or pan-Jcratch „