Glasgow University Library MS. Ferguson 49. 144 folios. 222x152mm. Bound in oak boards and leather. 16th Century. [Title on f1]: 'Summa perfecti magisterii Gebrii Regii super lapide phylosophorum editus anno domini 1350.' 1. f3 Incipit Summa perfecti magisterii Gebrii. [A number of pen drawings of furnaces and alchemical apparatus appear in the text.] [See Jabir ibn Haiyan, Summa perfectionis magisterii, Venetiis, 1475.] 2. f97 Liber de investigatione perfectionis magisterii. Geber. 3. f108 Incipit prologus libri de septuaginta. Est secretorum liber septuaginta. 4. f134 Incipit Opus Magni magistri Johannis de Rupescissa. Begins: 'Consyderavi tribulationes electorum...' [At end f143]: 'Explicit libri huius magisterii magister Johanis de Rupescissa ... anno dom 1350 die 4 octobr.' [Johannes de Rupescissa, Liber Lucis. See Singer, No. 293. Printed in Theatrum Chemicum, III, p. 284-191.]