Page:Popular Science Monthly Volume 43.djvu/98

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The decisive step in the knowledge of distillation was taken in Egypt. There were invented the first real distilling apparatus during the first centuries of the Christian era. They are described precisely in the works of Zosimus, an author of the third century, from the technical treatises of two women chemists named Cleopatra and Mary. In the margin of a Greek text of St. Mark are the drawings of the apparatus, and they agree exactly with the author's descriptions. The apparatus consists of a boiler or balloon-shaped receiver, in which the liquid was put; but the cover was replaced by a large tube topping the balloon, and ending above in a cap shaped like an inverted balloon, to serve as a condenser. The cap was furnished with lateral conical tubes inclined downward, which were intended to collect the condensed liquid and allow it to flow out into small bottles. All the essential parts of a distilling apparatus are here defined. These lateral tubes and their recipients constitute the chief improvement, and are what constitutes the alembic. Among the distinctive characteristics of the primitive alembic described by Zosimus is the multiplicity of the abductor tubes. He distinguishes between two-beaked and three-beaked alembics. The flow of vapor was simultaneous, though there were several beaks, and condensation took place in two or three receivers at once. Another figure represents an alembic with a single beak, to which a large copper tube was attached. An alembic described by Synesius, an author of the fourth century, and figured in less ancient manuscripts, shows the boiler with its cap, furnished with a single tube, the whole apparatus being heated in a marine bath. This form varied but little till the sixteenth century. The alembic passed from the Greco-Egyptian experimenters to the Arabs without any notable change. The Arabs were not, therefore, the inventors of distillation, as has been too often affirmed. In chemistry, as in astronomy and medicine, they merely reproduced the apparatus and processes of the Greeks, their masters, adding a few improvements in details. It is a mistake to trace the discovery of distillation and of alcohol to Rases, or Abulcasis, or other Arabian authors; the verified texts have at least furnished me no indication of that kind. In fact, Rases (tenth century), in the passages cited in support of that opinion, speaks only of vinous liquids or false wines obtained by the fermentation of sugar, honey, and rice; liquids, some of which, like hydromel, were known to the ancients. But there is nothing about distilling them, or extracting a more active principle, in any passage in Rases that I am acquainted with. In the pharmaceutical works attributed to Abulcasis or Abulcasim, a Spanish doctor of Cordova, who died in 1107, we only find a distilling apparatus for preparing rose-water which did not differ in principle from those of the old Grecian alche-