Page:History of the Royal Society.djvu/289

 try do no more than take it off the ground as clean as they can, and sell it to Merchant-strangers. This is, says he, the Barbary Peter, which the Refiners buy commonly at twenty shillings per Cent.

'Much after the same manner (by the relation of an Indian Merchant) is that great quantity of Peter produced, which of late years hath been brought into England, and other parts of Christendom, from about Pegu in East-India, saving that the Natives do refine it once, before they sell it to the Merchants: But being not so skilful, to discharge it from the common Salt, which attends Peter, our Workmen do refine it again, before it be fit for Gunpowder.

'The next remark out of Pliny, is, Aquæ vero Nitrose pluribus in locis reperiuntur, sed sine viribus Densandi (he means the heat of the Sun in those places) ''Optimum Copiosumque in Clytis Macedoniæ quod vocant Cbalastricum candidum purumque proximum sali. Lacus est Nitrosus, exiliente è medio dulci fonticulo, ibi sit Nitrum circa Canis ortum, novenis diebus, totidemque cessat, & rursus innatat & deinde cessat, iis autem diebus quibus gignitur si fuere imbres salsius Nitrum faciunt, Aquilones deterius quia Validius commovent limum. In Egypto autem conficitur multò abundantius sed deterius, nam fuscum lapidosumque est, fit penè eodem modo quo Sal: nisi quod Salinis mare infundunt, Nilum autem Nitrariis''.

'How such great plenty of Nitre should be found in the Waters above mention'd, will be no difficulty to conjecture, if we consider that Lakes are the receptacles of Land-floods, and that great Rains may easily bring it to the Lake in Macedonia, from the Rh