ACACIA 3 



resin, and a small quantity of the acid of amber, as well as tho peculiar body called 

 abictin. 



ABLETTE, or ABLE, is a name given to several species of fish, but particularly 

 to the Bleak, the scales of which are employed for making the pearl essence which is 

 used in the manufacture of artificial pearls. See PEARLS, ARTIFICIAL. 



ABRASION'. The figuration of materials by wearing down the surface. In 

 general, tho abrasive tool or grinder is exactly a counterpart of the form to be pro- 

 duced ; thus, for plane surfaces a flat grinder is employed, and for concave surfaces a 

 convex grinder. 



ABRATTM SALTS ((Abraumsalze, Ger., ' Salts to be removed'). Towards tho 

 upper part of the great salt deposits now extensively worked at Stassfurt, in Prussia, 

 the chloride of sodium becomes largely mixed with certain salts of potassium and 

 magnesium, representing the more soluble compounds which remained dissolved in 

 the mother liquor after the greater part of the chloride of sodium had been separated 

 by crystallisation. These mixed salts were formerly regarded as worthless, and were 

 hence termed Abraumsalze. Indeed the workings at Stassfurt having been originally 

 undertaken with the view of procuring common rock-salt, it was naturally considered 

 unprofitable to bore through the thick beds of impure salt before reaching tho 

 underlying deposit of purer chloride of sodium. The high commercial value of these 

 so-called Abraumsalze is now, however, fully recognised ; and at the present time 

 they are employed on a very large scale for the production of chloride of potassium. 

 In addition to the rock salt, the chief constituents of the Abraumsalze are the 

 minerals known as Camallite, a double chloride of potassium and magnesium; Sylvine, 

 or chloride of potassium ; and Kieserite, or sulphate of magnesia. Similar deposits 

 of salts are worked at Kalucz, in Hungary. See POTASSIUM, CHLORIDE OF. 



ABRUS PRECATORIA. The seeds, often strung together as rosaries and 

 necklaces, are well known as ' Prayer Beads.' They are of a brilliant scarlet colour, 

 with a black spot on one side, and are hence termed ' Crabs' Eyes.' In India, they 

 are used by druggists and jewellers as weights, the seeds weighing uniformly about 

 one grain each. The Abrus belongs to the Leguminosts, or Pea-order. 



ABSINTH. A liquor flavoured with wormwood (Artemesia absinthium, Natural 

 Order Composites) and other species containing the bitter principle termed absinthine. 

 To prepare absinth the leaves and flower-heads of the wormwood are steeped in spirit 

 somewhat above ' proof for several days, with other aromatic and stimulant herbs 

 such as angelica root, Calamus aromaticus, aniseed, dittany leaves and wild marjoram. 

 Tho liquid is then distilled, and the green essence thus obtained is mixed with certain 

 aromatic extracts. A brilliant tint is obtained by the use of indigo and other 

 vegetable colouring matters : sulphate of copper is said to have been employed for 

 this purpose ; and it is also asserted that the liquor is occasionally adulterated with 

 chloride of antimony in order to produce a characteristic milkiness. 



Absinth is largely prepared in Switzerland, especially in the canton of Neufchatel ; 

 and indeed the strongest liquor is often known in trade as ' Swiss absinth,' though it 

 may not have been prepared in Switzerland. Of late years, it has been drunk 

 immoderately in France, and large quantities are also consumed in America. Certain 

 French physiologists have alleged that the essential oils in absinth act as an energetic 

 poison, especially affecting the nervous system; other authorities attribute the 

 injurious effects of absinth-drinking to the Calamus aromaticus said to be used in its 

 preparation ; whilst others again maintain that the effects are merely those which 

 follow the long-continued use of any strong alcoholic liquor excepting, of course, the 

 poisonous action of any copper-salts which may be present in adulterated absinth. 



ABYSSIWIATT GOLD. A yellow metal of a fine colour if properly prepared. 

 It is an alloy of 9074 parts of copper and 8'33 of zinc. The ingot is plated on one 

 side with a thin plate of gold, and it is then rolled out into sheets, from which articles 

 of jewellery are formed in the usual way. The gold on the articles as sold varies from 

 - 03 to T03 per cent. This is also known as Talmigold. The term Abyssinian Gold 

 is sometimes applied in trade to Aluminium Bronze. See ALUMINIUM BEONZE. 



ACACIA. (Lat. acacia, a thorn ; Gr. &c^, a point). The acacia is a very extensive 

 genus of trees, or shrubby plants belonging to the Lcguminosa>. or Pea-order. The 

 acacias inhabit the tropical regions generally, but extend in some instances into the 

 temperate zone; being found, for example, in Australia and the neighbouring 

 islands. Botanists are acquainted with nearly 300 species of the acacia, some of 

 them yielding gum ardbic and other gums known in commerce ; while others give a 

 large quantity of tannin, especially a species which grows in Van Diemen's Land or 

 Tasmania. The Acacia vcra is a native of Arabia and of Africa from Senegal to 

 Egypt ; the A. Arabica is found in tho same countries and in India ; the A. Karoo 

 belongs to tho Cape of Good Hope, producing the Cape gum ; A. gumm\fera is chiefly 

 found in Africa near Mogador A. Scyal in Scnegambia ; A. tortilis grows in the 



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