5. Ultimum Testamentum. Of this work, which professes to give the whole doctrine of alchymy, there is an English translation. 6. Elucidatio Testamenti. 7. Potestas Divitiorum cum Expositione Testamenti Hermetis. 8. Compendium Artis Magicæ, quoad Compositionem Lapidis. 9. De Lapide et Oleo Philosophorum. 10. Modus accipiendi Aurum Potabile. 11. Compendium Alchymiæ et Naturalis Philosophiæ. 12. Lapidarium. 13. Lux Mercuriorum. 14. Experimenta. 15. Ars Compendiosa vel Vademecum. 16. De Accurtatione Lapidis. Several other tracts besides these are named by Gmelin; but I have never seen any of them. I have attempted several times to read over the works of Raymond Lully, particularly his Last Will and Testament, which is considered the most important of them all. But they are all so obscure, and filled with such unintelligible jargon, that I have found it impossible to understand them. In this respect they form a wonderful contrast with the works of Albertus Magnus and Roger Bacon, which are comparatively plain and intelligible. For an account, therefore, of the chemical substances with which he was acquainted, I am obliged to depend on Gmelin; though I put no great confidence in his accuracy. Like his predecessors, he was of opinion that all the metals are compounds of sulphur and mercury. But he seems first to have introduced those hieroglyphical figures or symbols, which appear in such profusion in the English translation of his Last Will and Testament, and which he doubtless intended to illustrate his positions. Though what other purpose they could serve, than to induce the reader to consider his statements as allegorical, it is not easy to conjecture. Perhaps they may have been designed to impose upon his contemporaries by an air of something very profound and inexplicable. For that he possessed a good deal of charlatanry is pretty evident, from the slightest glance at his performances. He was acquainted with cream of tartar, which he distilled: the residue he burnt, and observed that the alkali extracted deliquesced when exposed to the air. He was acquainted with nitric acid, which he obtained by distilling a mixture of saltpetre and green vitriol. He mentions its power of dissolving, not merely mercury, but likewise other metals. He could form aqua regia by adding sal ammoniac or common salt to nitric acid, and he was aware of the property which it had of dissolving gold.