6 



In this respect it differs, therefore, from the writings of two of 

 his contemporaries, viz., Roger Bacon (1214-1202-4), and Albertus 

 Magnus (1193 (?)-l 280). 



In his Opus Majlis, Bacon has given an encyclopedia of human 

 knowledge, and especially of physical science, but it is another 

 work of his which falls to be mentioned in this place, namely, his 

 " Epistoia (le secrttis operihus naturce et artis, et de nullitate 

 magice." This is a short rejjort on the very wonderful effects 

 that can be produced by natural means, and it is in this tract 

 that occurs the often-quoted allusion to the composition and 

 ])ower of gunpowder. This letter was intended as a reply to the 

 ])ersistent attacks of malignant ecclesiastics who accused him of 

 I)ractising " black magic " * — by showing that the ai)parent mystery 

 was due to the ignorance of his accusers and not to any compact of 

 his with the infernal powers. 



Albertus Magnus is credited with a tivatise of secrets, but the 

 authorship has been disputed and litis been assigned to Henricus 

 de Saxonia, one of his pupils, but whether tliis be correct or not 

 the work usually, if not invariably, beai-s the name of Albertus. 

 It deals with physiological secrets only, and that in a very brief 

 manner; so that, both in i-ange and in bulk, it is quite the reverse 

 of an encyclopaedia. Notwithstanding, if we may judge by the 

 number of editions, it was one of the most popular treatises from 

 the 15th to the 17th century, f Albertus was the author likewise 

 of a treatise on the secrets of plants, animals, and stones, in which 

 he described tlieir occult virtues. 



* The black magician, or necromancer, was believed to have carried on a 

 correspondence with the fiend and entered into a compact by which, on the 

 liberation of the latter from his "prison-house," he would assist the magi- 

 cian in carrying out schemes which, in their ex[)ected results, could be called 

 nothing else than supernatural. The correspondence, with the magician's 

 name at it, was usually brought up in evidence against him— very much 

 to his annoyance — when he had to implement his share of the bargain. 



tit is entitled "Dp Secretis Mulierum," and a list of the early editions 

 is given by Hain (Repert. Bibliogr., Nos. 549-568). In character it closely 

 resembles the ^' De phmoiiomia" oi Michael the Scot, and the two tracts 

 were frequently pi'inted together during the 17th century. It was trans- 

 lated into French and German. An edition of the French, (Cologne, 1722) 

 entitled " Les admirnbles s/'crcts d'Alljcrt ie Grand," contains, besides the 

 two tracts of Albertus, a third consisting of practical receipts, and a fourth 

 on physiognomy. 



