SAU

SE B

( 587 )

SAUNDERS WOOD.

There are three fpecies of wood known bythis name, the White , the Yellow , and the Red ,Of thefe the two former were never employedbut in medicine, and are now entirely difufed.T hefe two are procured from varieties of thefame tree, but the tree that yields the red faun-Aers is a totally different fpecies.

White and Yellow Saunders Wood. Thefewoods are brought over in large billets fromfeveral parts of the Eaft Indies, and are faid tobe chiefly the produce of the ifland Timor inthe Indian Ocean . The white Saunders is of apale yeliowifh white hue, and almoft taftelefs.It is feldom feen and requires no further noticein this place.

The yellow Saunders is of a pale yeliowifhcolour, a fragrant rofe fmell, and a bitterifharomatic tafte. There is feme doubt whetherit is not the fame tree that yields both the whiteand yellow, according to the difference of ageand foil. Both woods are hard and heavy.

The yellow Saunders diftilled with watergives a fragrant effential oil which thickens inthe cold to the confiftence of a balfam. Thewatery decoCtion yields a bitterifh fomewhatpungent extract.

Alcohol forms a fine yellow tindlure, whichafter the fpirit has been evaporated leaves afemi-fluid fragrant refin.

This wood is fcarcely ever ufed in Europe ,but is much valued in the Eaft for its fragrantfeent.

Red Saunders Wood. This wood (yielded bythe pterocarpus fantalinus) is alfo brought fromthe Eaft Indies, and comes over in round billetsof a blackifh red on the outfide, but of a deepbrighter red within and a wavy grain. Thoughwhen recent it appears to be highly fragrant, itis nearly without fmell or tafte in the ftate inwhich we receive it, and is folely valuablefor the deep red it gives out to alcohol. Waterffigefted with it has no effeCt on the red tinge,and only becomes of a pale yellow, but alcoholreadily acquires a fine bright full-bodied red.This tindfure yields a dark red extract amount-ing to near a fourth of the weight of the wood.The fixed oils are not coloured by red Saun-ders, but a few of the volatile oils receive are . , t 1 ” 1 S e - This wood is often confoundedwit Brazil wood, as they much refemble each’n appearance. They are however readilydiftmguifhed by this circumftance, that Brazilwood gives out its red colour to water as wellas alcohol, but Saunders wood only to alcohol.

* Vol, 70 and 7 a.

This latter circumftance renders this woodof no ufe in general dyeing, but it is occafion-ally ufed for colouring fpirits, as, for example,the red fpir/t ufed for thermometers.

SEA-WATER.

The compofition of fea-water and the modeof extracting the fait from it are deferibedunder the article Muriat of Soda. See alfoSulphat of Magnefta\ and Waters, Mineral.

SEBACIC ACID , or Acid of Fat. Fett-faure. Germ.

When any kind of animal oil is fubje&ed toa heat fufficient to volatilize it, feveral newproducts are formed, and among others a verypungent acid liquor may be collected by con-denfation, which has been particularly exa-mined by feveral chemifts, and having beenconfidered as a peculiar acid it has been termedthe Acid of Fat or Sebacic Acid . A fimilar acidmay alfo be procured from fat without diftilla-tion of the entire fat, in the way that will beprefently mentioned, whence this acid hasbeen fuppofed to exift naturally in fat in inti-mate union with the oily part. The propertiesof this acid, and the products of the diftfllationof animal oil have been particularly noticed byCrell in two very elaborate memoirs, publilhedin the Philofophical TranfaCtions, a of whichwe (hall give a very fhort extraCL

Since this period however another acid fub-ftance differing from the former in many effen-tial particulars (efpecially in being free fromfmell J has been difeovered by Thenard, b whichhe confiders as the true febacic acid, and thepungent acid of Crell and other chemifts, heafferts to be chiefly a modification of the ace-tous acid. But as feveral objections might beraffed againft this opinion, we lhall give theexperiments of each chemift.

Thofe of Crell are in a few words, the fol-lowing:

A quantity of beef fuet was firft melted and{trained to feparate all the impurities: 2 lbs. ofthis were put into a glafs retort fet in a rever-beratory fand-bath, and a receiver was clofelyluted on. Heat was applied, by which thefuet firft melted then diftilled quietly with agentle frothing. There firft came over intothe receiver a thin limpid oil which did notcongeal, after which came an acid liquor,mixed with a denfer and coloured oil, theformer of w-hich remained fluid, but the lattercongealed in the receiver. This mixed productcontinued for fixteen hours, at the end of whichthe retort was fully red-hot, and every thing

k An. Chim. tom. ij.