DISCOVERY OF ALCOHOL AND DISTILLATION. 89 



mists. The Arabs, therefore, were still, in the beginning of the 

 fourteenth century, using the complicated apparatus of the Greco- 

 Egyptians. 



Alembics with several beaks were still employed by the Western 

 alchemists in the sixteenth century. In Porta's treatise, entitled 

 Natural Magic, a collection of processes or secret operations, the 

 author mentions the cap of three and four beaks, each furnished 

 with its tube and receiver. It is still the old apparatus of Zosi- 

 mus. Porta, however, describes two important improvements 

 which have come down to modern industry graduated condensa- 

 tions during the same operation and the cooling worm. We need 

 not suppose that he invented them, but only that he described the 

 practice of his time. The new feature is as follows : In the alem- 

 bics described by Zosimus the three pipes are at the same level, 

 and doubtless disengaged an identical vapor; the ideas of the 

 chemists of the time were too vague to allow anything else to be 

 expected. The three tubes of Porta, on the other hand, are at 

 different heights, arid the author adds that the highest tube fur- 

 nishes the purest spirit. We can already discern the ideas that 

 have fructified in our apparatus for fractional rectification, with 

 series of superposed chambers and trays delivering alcohols of 

 higher degrees of concentration from the higher levels. This ar- 

 rangement, however, was abandoned; at least we find no more 

 trace of it during the following centuries. In this as in many 

 other incidents, the men of the sixteenth century foresaw the most 

 modern advances, but by a kind of intuition, without their having 

 those clear notions and those exact principles of physics which, 

 being wanting, progress is accidental and transient. 



Another more durable improvement was that of the worm. 

 The alembics of the ancient Greeks doubtless permitted distilled 

 liquors to be obtained, but on condition of operating slowly and 

 with a very moderate heat. In fact, the vapors were imperfectly 

 condensed on the small surfaces of the tubes and the caps repre- 

 sented in the manuscripts. However little we might try to hasten 

 the distillation, the receivers would become warm and condensation 

 would become almost impossible. Hence the ancient authors pre- 

 scribed that their apparatus should be heated over very slow fires. 

 They operated by means of sand baths, baths of ashes, or water 

 baths. Sometimes they tried to distill with no other heat than 

 that of fermenting manure or a low fire of dung or sawdust. 

 Their operations were therefore very slow, and often lasted for 

 days and weeks. It required fourteen days, or twenty-one days, a 

 text would say, to perform the operation. Not only did they in 

 this way assure the effect of digestions and cementations, designed 

 to produce gradual permeation with sulphurous and arsenical 

 vapors, into sheets of metal submitted to the tinctorial action of 



