114 SUGAR. 



yellow, which becomes 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. Ciievreul* 



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 Ccesalpinia. 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 Campechy wood ; the col- 

 oring matter which characterizes it has 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 furnished by the Plarocarpus san- 

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

 Peltier.f 



To conclude., the yellow dye-woods of commerce are Fustic, i?/m* 

 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 Morus tinctoria. 



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 quantity of saccha- 

 rine matter contained in vegetables in general is invariably diminished 

 at the period of formation of the seed. Sugar, consequently, as well 

 as starch, appears to contribute to the production of the seed. 



The very characteristic taste of 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 

 Ixi the name. True sugars, according to chemists, have one properi) 

 which distinguishes them from all substances with which they maj 

 have, in other respects, the greatest analogy ; this characte;isti» 

 property is that of becoming changed, under the influence of wato 

 a suitable temperature, and contact with yeast, into alcohol and cai 

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

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

 fermentation, yield alcohol. I have already quoted starch as coming 

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

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

 are first chnnged into sugar, which subsequently undergoes the vi 

 nous fermentation. 



* Chimie appliqu^e a la teinture, 30e le^on, p. 88. 



t Chevreol, Cheoiistry applied to dyioe, 30tb Uctor*, p. WL 



