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PROPERTIES OF PHOSPHORIC ACID.

PHOSPHORIC ACID,

PART LXXX.

VV HEN phosphorus is united to oxigen the result is an acid,which varies according to the quantity of oxigen which joins to^ the phosphorus. Phosphorus saturated with oxigen forms phos-phoric acid.

PROPERTIES OF PHOSPHORIC ACID.

Phosphoric acid is capable of existing in a dry and crystallizedstate. When solid, and placed in contact with a small quantityof water, it dissolves, and affords a ponderous transparent fluid,void of odour. When exposed to heat it is rendered viscous j itgradually becomes more consistent, and loses its transparency.Lastly, when urged by a violent heat, in a silver or platina cruci-ble, it melts into a transparent glass, which again attracts moisturewhen exposed to the air, and becomes converted into liquidphosphoric acid. When melted in an earthen crucible the acidacts upon it and fuses into a glass, which is not soluble in water,and exhibits no signs of acidity. It has a strong attraction forall the alcalies, and likewise for the earths. It acts only on asmall number of metallic substances.

METHODS OF OBTAINING PHOSPHORIC ACID.

1. To obtain phosphoric acid the bones of adult animals aregenerally made use of. For that purpose, dilute in a spacious