384 Alfred J. Ewart : 



gummy residue of reducing sugar, apparently mainly or wholly 

 pentose. 



Aniline uater is feebly alkaline. It gives a dense white precipi- 

 tate with formaldehyde in concentrations down to 0.05 %. The 

 white ppt. formed by adding 500 c.c. of saturated aniline water to- 

 50 c.c. of 1 % formaldehyde sniells of the latter even| after 3 days' 

 boiling. On evaporating to dryness and extracting the resinous 

 residue (which is probably an analogous compound to Bakelite)' 

 witli water, a trace of reducing pentose sugar was obtained. 



The joitit action of alkalies. 



Since a mixture of caustic soda and lime appears to be more- 

 effective in polymerizing formaldehyde to sugar than either singly^ 

 it seemed worth while to try the effect of lime produced directly in. 

 tlie boiling formaldehyde. A preliminary experiment performed 

 by added 5 % caustic soda to 250 c.c. of boiling 1.6 % formal-^ 

 dehyde containing^ in one case 0.8 % calcium chloride, and in the 

 other no calcium chloride showed that all the formaldehyde was- 

 converted into formates and sugar in the first case with an addi- 

 tion of L'3 c.c. of sodium hydrate, and i,n the other of 24.5 c.c, 

 while the amount of sugar formed was approximately three times- 

 greater in the former case. The other products were calcium 

 formate and sodium chloride. 



lo determine the best concentration for the reaction, 5 c.c. of 

 40 % formaldehyde and 5 c.c. of 17 % calcium chloride (anhydrous) 

 were added to varying amounts of water, and 3.5 % sodium hydrate- 

 run into the boiling mixture until the reaction was completed. 



nioiiiit of Water 



Amount of 3.5'{ NaHO 



present. 



required. 



35 c.c. 



11.8 c.c. 



60 c.c. 



9.9 c.c. 



110 c.c. 



8.7 c.c. 



260 c.c. 



8.0 c.c. 



510 c.c. 



9 8 c.c. 



760 c.c. 



10.2 c.c. 



1010 c.c. 



11.4. c.c. 



The concentration represented by the addition of 250 c.c. appears 

 to be the best. 



Hence using 5 c.c of 40 % formaldehyde in 250 c.c, and adding 

 varying amounts of Calciimi chloride, the amounts of caustic soda, 

 required to complete the reaction were : — 



