182 A. J. Ewart: 



The i>roduction of sugar from solids. 



If dry (CHjOjj is mixed with crystalline Barium hydrate (Ba 

 HoOo 8 H2O) and ground intimately in a mortar, a pasty mass is- 

 obtained, smelling of CHoO. If this is gently warmed at one point 

 a sudden and violent exothermic reaction spreads through the mass, 

 CHoO, water vapour and n)ethyl alcohol are given off, and the 

 teimperature rises, to lOCC. oi-* llO'C. if a large mass is used, witk, 

 an excess of barium hydrate. The resulting brown, gummy residue- 

 contains no formaldehyde, but reducing sugar appears. 



Similar reactions are given with strontium hydrate, but with 

 dry calcium hydrate tlie reaction is imperfect. " Paraformalde- 

 hyde" and the solid polyhydrate may be used instead of metafor- 

 maldehyde. In the latter case the temperature does not rise beyond' 

 lOO^C owing to the large escape of steam. 



Metaformaldehyde and alkali. 



The solid was ground with dry barium liydrate in varying mole- 

 cular proportions, and the j^asty mass weighed out to contain in 

 each case 0.45 gram (CH20)3, After warming, the residue was dis- 

 solved in Avarm Avater, the Barium formate and any excess of 

 Barium hydrate precipitated as sulphate, and the filtrate tested by 

 the Pavy method. Any (CHjO), remaining is filtered off with the 

 Barium sulphate, and if any CH,-0 is present, the ammonia used' 

 the Pavy method. (Any (CHiO)^ remaining filtered off witli tlie 

 affect the tests for reducing sugar. Similarly the formic acid is 

 converted into ammonium formate. As a matter of fact the 

 reaction is a very complete one, and with the proper proportion of 

 barium hydrate every trace of formaldehyde is removed. 



Tlie following proportions were used : — 



A and B. 1 Barium hydrate (0 80 otmiii) to 1.8 (CH.,0)3 (0.45 gram) 

 C 1 „ „ (0.42 „ ) to 3.6 (CH2O), (0.45 gram) 



D and E. 1 „ „ (0.28 „ ) to 5.4 (CH,,0)3 (0.45 gram) 



with the foUowinsx results — 



5.4 „ „ U.14 pale yellow 0.0G6 



