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METHOD OF PURIFYING PHOSPHORUS.

water to a small depth, and the phosphorus as it comes over willfall in drops to the bottom.

Rationale. ..In this process the sulphuric acid unites with thecalcareous earth of the hones, and forms sulphate of lime; andthe phosphoric acid of the bones becomes disengaged, and re-mains dissolved in the liquor. The charcoal at an elevated tem-perature takes the oxigen from this acid, and carbonic acid gasis formed, and phosporus passes over.

METHOD OF PURIFYING PHOSPHORUS.

Phosphorus obtained in either manner is of a dirty blackishcolour, and soiled with a certain quantity of charcoal and halfburnt phosphorus, which gives it that appearance. In orderto purify it, it must be put into a piece of chamois leatherand closely tied up in it. The whole is then immersed in a ves-sel of boiling water, the phosphorus melts and may be pressedthrough the leather, taking care to keep it under the water.

It is better however to purify phosphorus by a second dis-tillation.

Dr. Higgins purified it, by means of hidrogen gas.*

METHODS OF MOULDING PHOSPHORUS INTOCYLINDERS.

In order to form phosphorus into sticks, a funnel with a longneck may be used, the lower orifice of which is closed with acork; the funnel is then to be filled with water and phosphorusput in it, and this being plunged into boiling water, the heat com-municated to the funnel melts the phosphorus, which runs intothe neck and acquires that form. The funnel is then removed

* Minutes of the society for philofoph. exper. &c.