Leiden MS. Vossianus Chym. Q. 42. 192 folios. Paper. 196x158mm. 16th Century [shortly before 1533.] 1. f1-28v Pseudo Albertus Magnus (or pseudo Bacon), Semita recta. 2. f29-48v [84 recipes taken out of Aristotle ?], De perfecto magisterio. 3. f49-58v [35 recipes taken out of the 'Liber multiplicationis de transmutatione metallorum'.] 4. f58v-59r [Two recipes.] 5. f59-61 Secreta Virgilii: De lapide dabessi. 6. f61-63v Secreta Virgilii: Liber aquarum. 7. f63v-70 [Various formulae.] 8. f70-98 De ortu Solis. 9. f99-101 Pseudo Raimon Lull, Semita semitae [?] [extracts.] 10. f101 [Verse.] 11. f101v-114v Roger Bacon, De naturis metallorum et transformatione ipsorum [without the 'prooemium'.] 12. f115-128v [Untitled work without a heading, beginning "In nomine sancte er individue trinitatis... dicta philosophica summa cum diligencia radicaliter iuxta mei sensus pravitatem cupio explicare".] 13. f129-131 [6 recipes, extracts from a Czech book.]