Page:Willich, A. F. M. - The Domestic Encyclopædia (Vol. 1, 1802).djvu/187

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BAR H. The Dipsari/s fuUonum, L. or Manured Teasel ; and 12. Ail the species of the Cynara and Cardans, L. or theAaTiCHOKE and Thistle, when cultivated either on the sea- shore, or in any soil irrigated with sea-water. Barilla, as an article of trade, ought to possess the following pro- perties : it should be firm, hard, and heavy, though porous ; dry, and sounding on percussion ; of a blneish colour, and impart, on breaking it, a flavour slightly resem- bling that of the violet. By these criteria, it may be easily distin- guished from pot-ash, though it would be difficult to procure a ba- rilla consisting purely of mineral alkali ; as the very best sort of the former generally contains a small proportion of common salt. Ac- cording to tlie experiments made by Mr. Kir wan, and published in tire first volume of the Transactions of the. Jlcnjal Irish Academy, in 1/S9, the barilla exported from Spain, contains carbonic acid, carbon, lime, clay, and silicious earth ; but such as is very pure, also contains both common and Glauber's salt, and water. From the small quan- tity of carbonic acid discoverable in Spanish barilla, he concludes that its mineral alkali is for the most part combined with it in a pure or caustic state 3 and that its blueish colour must be ascribed to the matter of carbon : in a similar way, he attributes the green or blue colour of pot-ash to its combination with magnesia. This important article of com- merce is, in proportion to its degree of purity and strength, classed ac- cordirg to the following places, from which it is imported : 1 . The barilla made at Alexandria ; 2. That BAP. [163 from Alic'ant; 3. Garthagena ) and 4. B'jurde, or Smyrna. Various methods and schemes have, in this country, excited f e . ingenuity oi syrculat.-. ei i ■-.. in the lion of tins valuable sub- stance, for which large stuns are anriually paid at foreign marl. Those of our readers, who apply their attention to experiments of this useful nature, will, perhaps^ be gratified by the following speci- fication of Mr. James Kixg's pa- tent for his new-invented British barilla, granted in 1/30. As his exclusive privilege is now expired, we shall communicate the process nearly in the patentee's own words. He first takes a quantity of ashes obtained from burning the loppings or branches of ash- wood, oak, beech, elm, alder, and any other kind of green wood and bramble, in the proportion of one-fourth; and a similar quantity of ashes ob- tained by burning the green vege- tables, known by the name of fern, brecon, bean and pea-straw, and wdiin-ashes; also common field and highway thistles ; the stalks of raps and mustard seed; and the bent, or rushes, that grow by the sea- shore. One half oi the ingredients being thus procured, they are then passed through a fine siev»j. pfaactd on a boarded floor, andcaie : ;.. 'y mixed widi a similar quauuty (making the other half) ci soap* boilers' waste ashes, which must beintimateiy blended together with a shovel. Next, he acids one hun- dred weight ef quickdimeto twelve times that quantity of the ether materials, and likewise ii<ler- tliem tboro'ughly. After this pre- paration, the whole is put into large square iron, pans, and a suf- ficient quantity of sea-water is M'2 poured