750 SACCHARINE SUBSTANCES. 



bonate of lime form in it. The compound of sugar and barytes 

 is similar, according to Peligot's analysis, as corrected by 

 Liebig, or C 12 H 9 O 9 + BaO, HO. The compound of sugar and 

 oxide of lead, C 12 H 9 C 9 + PbO, is prepared by dissolving 

 oxide of lead in a boiling solution of sugar ; it falls as a white 

 precipitate, which is had perfectly pure by washing it with 

 boiling water, which does not dissolve it, and drying ; a so- 

 luble compound of sugar and oxide of lead is retained in the 

 liquor which gives the precipitate. A crystalline compound of 

 sugar and chloride of sodium is formed on allowing a solution of 



1 part of common salt and 4 parts of sugar to evaporate spon- 

 taneously in air, the solution being decanted several times from 

 the crystals of sugar-candy, which are first deposited. The 

 crystals of the compound in question have a taste at once sweet 

 and saline, and run into a liquid in humid air ; their formula is 



2 C 12 H 9 O 9 -f Na Cl, 3HO:* It is probable from the composi- 

 tion of this salt, that the usual equivalent of sugar should be 

 multiplied by two, if not by a higher number. 



Caramel, C 12 H 9 O 9 . At a temperature a little above its point 

 of fusion 356(180 cent.), sugar becomes brown, and at 410 or 

 428 (210 or 220 cent.) swells up and becomes a black porous 

 shining mass, which is known as caramel, losing nothing but 

 two atoms of water. It is obtained free from sugar, and 

 the bitter products which accompany the caramel of the shops, 

 by solution of the black mass in a small quantity of water, and 

 precipitation of the caramel by alcohol, which retains the impu- 

 rities in solution. Caramel is a black or very dark brown 

 powder, neutral and insipid, soluble in water, to which it gives 

 a fine colour of sepia, and not fermentable. It has the same 

 composition as sugar in the oompound of sugar and lead, 

 C 12 H 9 O 9 (Peligot) ; it precipitates salts of barytes and basic salts 

 of lead. Grape sugar furnishes the same product by heat. At a 

 higher temperature, caramel loses more water, and forms an in- 

 soluble matter ; when still more strongly heated it affords combus- 

 tible gases, and leaves a bulky charcoal, difficult of incineration. 



Metacetone, C 6 H 5 O (Fremy), a combustible liquid, obtained 

 mixed with acetone, by distilling a mixture of 1 part of sugar 



* Peligot ; Recherches sur la nature et les proprtete's chirniques des sucres, 

 An. de Ch. &c. t. 67, p. 113 ; et sur la composition du saccharate de plomb. Ib. 

 t. 73, p. 103. 



