236 APPENDIX. 
certain that the greater portion of the saccharine matter of the juice 
is crystallizable, and may be obtained in the state of crystals, if, after 
rapid boiling and filtering, the clear fluid be quickly evaporated, the 
latter operation being a condition of absolute necessity in sugar 
making, as, by slow boiling, at a temperature of 212°, or even 
exposure for a considerable time to a temperature below the boiling 
point, glucose may be formed from the purest crystallized sngar dis- 
solved in water. On the contrary, if the concentrated solution of 
sugar be heated beyond 230° F., it undergoes alteration, and is 
changed, at least in part, into uncrystallizable sugar, or saccharine 
mucilage. When we consider how nearly allied these varieties of 
sugar are, and likewise how nearly allied in their composition they 
are to other substances, such as gum, starch, woody fiber, &c., we 
cannot be surprised either at the conversion of one kind of sugar into 
another, or into these substances, or at the formation of sugar from 
them. The above-named substances are chemically zsomeric ; that is, 
nearly identical in composition, so far as their elements are concerned, 
and the proportions of these elements, though the substances, gum 
and sugar, are so different in their properties. These reflections 
may be applied with as much force to the results obtained in the 
elementary analysis of various kinds of sugar, presented in the follow- 
ing table: 
Carbon. Oxygen. Hydrogen. 
42-47 50°63 6°90 Gay-Lussac and Thenard. 
Cane sugar, . . 42:22 51:17 6°60 SBerzelius.* 
42°85 50°71 6°44 Prout. 
Grapesug.(glucose,) 36°71 56°51 6°78 Saussure. 
teenage ger MS 1 37°29 55°87 6°84 do. 
& > *\).36°20° -56°75. - 7-05 Prout. 
Sugar of honey, . 36°36 56°58 17-06 do. 
38°53 54:60 6°87 Saussure. 
Sugar of manna, .<{ 38°70 54:50 6:80 Prout. 
44:10 49:76 6:13 Henry and Plisson 
Glycerin,. . . . 40°08 51:00 8-92 Chevreul. 
38°82 53°83 724 Gay-Lussac and Thenard. 
Sugar of milk, . .< 45:26 4834 6:38 Berzelius. 
40°00 53:36 6°63 Prout. 
* The first analysis published by Berzelius differs considerably from this, being 
carbon, 442; oxygen, 4001; hydrogen, 6-78; Berthellot and Saussare obtained 
results corresponding with those of Guy-Lussac. 
