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PROPERTIES OF OXALIC ACID.

OXALIC ACID*

PART XCIII.

PROPERTIES OF OXALIC ACID.

vJ'XALIC acid is always concrete, its crystals are quadrila-teral prisms, having their sides alternately broad and narrow,and terminating in two-sided summits. It is particularly dis-tinguished by its strong attraction to lime, which is superior tothat of any other acid. It is not altered on exposure to air. Itacts upon most of the metals. Exposed to heat it becomesdecomposed into carbonic acid, and carbonated hidrogen gas. Itcontains more oxigen than any other vegetable acid,

METHOD OF OBTAINING OXALIC ACID.

Oxalic acid is generally prepared by oxigenating sugar, in thefollowing manner: Pht one part of white sugar into a retort,and pour over it four parts of nitric acid, of about 1 .567 spec,grav. adapt a receiver, and make die solution boil. Whenthe fluid in the retort acquires a brown colour, add three partsof acid more, and continue the boiling till it again becomesbrown, then add two parts more of acid, and continue theheat till the red fume almost disappears. Having done this,