PROPERTIES OF SULPHUREOUS ACIO.

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SULPHUREOUS ACID.

PART LXXIX.

This constitutes the imperfect degree of oxigenation of sul-phur; that is to say, the sulphur is not fully saturated with oxi-gen. Sulphureous acid naturally exists in the gazeous state.

PROPERTIES OF SULPHUREOUS ACID.

The acid properties of sulphureous acid are not considerable.It does not redden blue vegetable colours, but on the contraryrenders them white. It exerts little action on metallic sub-stances, and has a feeble attraction for the alcalies and earths. Itis exceedingly volatile, and assumes the state of gas, if moisturebe excluded.

For a fuller account of this acid we refer our reader back tosulphureous acid gas, vol. I, p. 317.

METHODS OF OBTAINING SULPHUREOUS ACID.

I. To prepare sulphureous acid, take one part of mercury andfour of concentrated sulphuric acid, put them into a retort, fur-nished with a receiver, and connected with Burkitt’s or Pepys’s