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through a long platinum syphon, surrounded by another pipe filled with cold'■ 1102 shows my contrivance for this purpose.
The under stopcock a, being shut, and the legb, being plunged to nearly the bottom of the still,the worm is to be filled with concentrated coldacid through the funnel c. If that stopcock is nowshut, and a opened, the acid will flow out in suchquantity as to rarefy the small portion of air in theupper part of the pipe b, sufficiently to make thehot acid rise up over the bend, and set the syphonin action. The flow of the fluid is to be so regu-lated by the stopcock a, that it may be greatly-cooled in its passage by the surrounding cold waterin the vessel /, which may be replenished by meansof the tube and funnel d, and overflow at e.
A manufacturer of acid in Scotland , who burnsin each chamber 210 pounds of sulphur in 24 hours,being at the rate of 420 pounds for 20,000 cubicfeet (= nearly 2000 metres cube), has a product ofnearly 3 pounds of concentrated oil of vitriol for’ every pound of sulphur and twelfth of a pound ofnitre. The advantage of his process results, I con-ceive, from the lower concentration of the acid inthe chambers, which favors its more rapid produc-tion.
The platinum retort admits of from 4 to 6 opera-tions in a day, when it is well mounted and man-aged. It has a capital of platinum, furnished with^"th n ? c ' £ > which conducts the disengaged vapors into a lead worm of condensation ;<o n ® e liquid thus obtained is returned into the lead pans. Great care must be taken
Invent
c »Ul
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any particles of lead from getting into the platinum vessel, since at the tem-
s of boiling sulphuric acid, the lead unites with the precious metal, and thus'vittj ! , es in the retort. These must be repaired by soldering-on a plate of platinumfief
l he separate oven or hearth for burning the sulphur in contact with the nitre"bti this combustible mixture was introduced into the chamber itself, spread on
v er y j or earthen pans, supported above the water on iron stands. But this plan was0q e ° r ious and unproductive. It is no longer followed.
' v ithoi n 0t H le characters of the good quality of sulphuric acid, is its dissolving indigo
Sip., tiering its fine blue color.
Uric ueid, when well prepared, is a colorless and inodorous liquid, of an oilyStiii Assessing a specific gravity, in its most concentrated state, of 1-842, when re-«ut t as found in commerce, of 1-845. It is eminently acid and corrosive, so\ v -j, ln "'e drop will communicate the power of reddening litmus to a gallon of water,fls S { * u produce an ulcer of the skin when allowed to remain upon it. If swallowed into ^ Sest state, in even a small quantity, it acts so furiously on the throat and stomachtl ’ a Snes ' USe * nt °lerable agony and speedy death. Watery diluents, mixed with chalk orv tee s W are the readiest antidotes. At a temperature of about 600° F., or a few de-h «st J >el °w the melting point of lead, it boils and distils over like water. This is theHioh ]; • ^ procuring sulphuric acid free from the saline and metallic matters withThe s .° me times contaminated.
,?hcer u . ’*5’ °1 sulphuric acid for water is so strong, that when exposed in an openJfhies j’t- lm bibes one-third of its weight from the atmosphere in 24 hours, and fully six!°Ur p s height in a few months. Hence it should be kept excluded from the air. If°tt) } )r ■ s > by weight, of the strongest acid be suddenly mixed with one part of water,?.*ber i,, ' 1 -] at 50° F., the temperature of the mixture will rise to 300°; while, on theI'tWery . four parts of ice be mixed with one of sulphuric acid, they immediatelyar'^een tt • S ' n k tbe thermometer to 4° below zero. From the great attraction existingtl a 1tteoi MS ac '^ an< l water, a saucer of it is employed to effect the rapid condensation- s v apor as it exhales from a cup of water placed over it; both standing under
t Won 1 ! austet l
receiver of an air-pump. By the cold produced by this unchecked evapo-
..Tq det=l aca °> the Water is speedily frozen-u. Cl ermm„ «.». .. „ r i »_ :a
m ] n . e purity of sulphuric acid, let it be slowly heated to the boiling pointbv lC 8 *Uell an y v °latile acid matter be present, it will evaporate, with its character-J j V ap 0raJ - presence of saline impurity, which is the common one, is discovered^er s> jp n * a given weight of it in a small capsule of platinum placed on red-hotfoore than two grains remain out of 500, the acid may be reckoned to be