SAL Vy^lthout Inducing aftual putrefac- tion ; 3. The earth employed ought to be of a loose and porous texture ; for instance, the clay of old mud- walls, or a due admixture of chalk, quick-lime, &c. ; 4. A sufficient length of time, namely, from six to twelve months, and up- wards ; as, otiierwise, a very small quantity of nitre will be obtained by crystallizing the ley made of the saltpetre-rot, or the earth after it has been exposed to the influ- ence of the atmosphere in triangu- lar beds, under proper sheds. — The manner of extrafting such earth is exceedingly simple and easy, by means of tubs with nume- rous holes at the bottom, lined with straw, over which the mould is placed in alternate strata ; with a little pot-ash either strewed be- tween Uiera, or dissolved in the boiling water, which is gradually poured over the solid materials : there is nothing farther required, than proper wooden pails with transverse sticks, in which the li- quor, after evaporating it to a pro- per consistence, is poured and suf- fered to stand for several days, slightly covered, till the crystals are formed. The remaining fluid, or mother-ley , is again to be boiled, and poured over a new portion of the earth taken from an old nitre- bed, so that none of it may be wasted. — Such is the process that is generally followed in the most profitable saltpetre- works of Ger- many. Though nitre affords one of the most extensively useful articles in the arts and manuftiftures (see AauA-FOETis), as well as in me- dicine, yet this powerful salt, when inadvertently taken in too large quantities, is one of the most fatal poisons. There are several attest' no. XIII.— VOL. IV. SAL ['7 ed cases on record, in which from half to a whole ounce of saltpetre has occasioned violent vomiting, convulsions, swelling, and other painful symptoms in persons who, by mistake, had swallowed it in a dissolved state, instead of Glau- ber's, or similar salts. — The most proper antidotes, in such distressing situations, will be a scruple or half a dram of i^iecacuanha with a tea- cupful of sweet-oil, and a large quantity of warm water to be drunk after it, to promote its operation as an emetic. Where this remedy cannot be procured on the spar of the occasion, it will be necessary to make use of copious and frequent draughts of mucilaginous decoc- tions of marsh-mallows, pearl-bar- ley, salep, or arrow-root powder, sago, tapioca, &-c. after which a gentle opiate will aflbrd the de- sired relief. In all instances of this nature, however, it will be advisa* ble immediately to resort to medi- cal advice. SALTWORT, or Glasswort, Salsola, L. a genus of plants com- prising nine species, of which two are indigenous : namely, 1. The kali, Prickly Salt- wort, or Kelpwort, grows fre- quently on sandy sea-shores, and flowers in the months, of July and August. 2. Thcfruticosa, Shrubby Salt- wort, or Shrub Stone-Crop, thrives likewise on sandy sea-sliores, and flowers in the month of Au* gust. Both these species are used for making the salt known under the name of kali, considerable quanti- ties .of which are employed in the manuftiftureof glass. — Theprocess is as follows : A trench being dug near the sea, laths are placed across it, on which die herb is laid in C heaps j
