114 SUGAR,' 



yellow, which hccomes brown with age ; this wood, besides a variety 

 of alkaline and earthy salts, of volatile oil and unazotized matter, 

 contains a particular coloring principle, called hematine, discovered 

 by M. Chevreul* 



The mahogany grows in the hot intertropical regions of America ; 

 Mexico and some of the West India islands export considerable 

 quantities. 



Pernambuco or Brazil-wood is the name given in trade to the 

 trunks of several trees of the genus Casalpinia. The Casalpinia 

 crista of Jamaica, the C. sappan of Japan, the C echinata of Santa 

 Martha, afford kinds that are very much prized. In point of chemi- 

 cal composition Brazil-wood agrees with Campechv wood ; the col- 

 oring matter which characterizes it lias been named Braziline by M. 

 Chevreul ; it is obtained in small crystals of an orange color. 



This wood comes to Europe in fagots of about 39 inches in 

 length. Red Saunders- wood is furnislied by the Plarocarpus san- 

 talinus ; it contains a peculiar dye stuff, santaline, observed by M. 

 Peltier.t 



To conclude, the yellow dye-woods of commerce are Y ustic, Rhus 

 cotinus, of the family of turpentine trees, a native of the south of 

 Europe, and the Cuba and Tampico woods, which are probably va- 

 rieties of the Moras linctoria. 



OF SUGAR. 



Sugar is met with in almost every part of vegetables ; it has been 

 found in flowers, in leaves, in stems, and in roots. It is less abun- 

 dant in seeds ; and it may even be said that the quantitv of saccha- 

 rine matter contaitjed in vegetables in general is invariably diminished 

 at the period of ft»rmation of the seed. Sugar, consecjuenlly, as well 

 as starch, appears to contribute to tlu) pr«»duction of the seed. 



The very characteristic taste <»f sugar generally suffices to pro- 

 claim its presence ; nevertheless, it would be a great mistake did 

 we rely upon this character alone for discovering the presence of 

 sugar; several substances possess a very decided sweet taste, with- 

 out being on that account sugar, in the sense which chemists attach 

 ;,o the name. True sugars, according to chemiists, have one proj)eriy 

 which distinguishes them from all substances with which they may 

 have, in other respects, the greatest analogy ; this characteristic 

 property is that of l)ecoming change. I, under the influence of water, 

 a suitable temperature, and contact with yeast, into alcohol and car- 

 bonic acid. It is certain, nevertheless, that certain bodies which do 

 not belong to the chemical genus, sugar, may, under the influence of 

 fermentation, yield alc(»hol. 1 have alieady quoted starch as coming 

 under this head ; but it has been distinctly ascertained, as 1 have also 

 said, that such substances, under the influence of the ferment itself, 

 are first changed into sugar, which subsequently undergoes the vi- 

 nous fermentation. 



♦ Chimio nppliqute I'l la tciiuuro, '30e le^on. p. 88. 



t Chevreul, Clicinistry applied to dying, 30lh lecture, p. M. 



