Chemical Science. 393 



lively insoluble. This sugar also is converted by nitric acid, 

 not into mucous acid, but into an acid of a particular kind. 



If nitric acid be added to the sugar of gelatine, it does not 

 at first appear to dissolve it, but on heating carefully, a solution 

 is obtained without the liberation of any red vapours, and oh 

 evaporation and cooling, a crystalline mass is obtained, which 

 when pressed in paper re-dissolved and re-crystallized is nitror 

 saccharine acid and far surpasses in weight the sugar used. 



This acid is very soluble. It crystallizes in beautiful co- 

 lourless prisms transparent, flat, and striated like Glauber's 

 salt. Its taste is acid and slightly sweet, and resembles that 

 of tartaric acid. When heated it swells, fuses in part, and emits 

 a sharp vapour. It does not affect earthy or metallic solutions. 

 It forms a neutral and a super-salt with potash, which crystallize? 

 in needles ; these thrown on coals detonate like salt-petre.. 

 It dissolves carbonate of lime with effervescence, and yields 

 needle-form crystals, which are not deliquescent and not soluble 

 in alcohol. Thrown on hot dodls these crystals fuse and de- 

 tonate like nitre. Its salt with copper is crystallizable and un- 

 changeable in the air. Its magnesian salt is deliquescent and 

 uncrystallizable. With lead the salt is uncrystallizable, unaltered 

 by the air, and resembles gum ; this salt when throv.n into the 

 lire produces a kind of explosion. This acid dissolves iron and 

 zinc, and disengages hydrogen gas. The salts are uncrys- 

 tallizable. 



The action of sulphuric acid on muscular fibre was next 

 examined by M. Braconnot. A portion of beef in small particles 

 was put into much water, and pressed several times to separate 

 every thing soluble. 30 parts of this fibre were mixed with 

 as much sulphuric acid, the fibre softened and dissolved 

 without the production of calour, or the disengagement of 

 sulphurous acid. It was slightly heated, and on cooling, a 

 layer of fat separated from the surface. It was then diluted 

 with water and boiled for nine hours, saturated with chalk, 

 filtered, aud evaporated. The extract was not sweet, but had 

 a decided taste of ozmazome. When rai.^ed with potash it 



