8o 



HISTORY OF SCIENCE. 



forms of apparatus, which, in modified shapes, may still be seen in 

 the laboratory. For instance, Fig. 31 represents the alchemical ap- 

 paratus for distillations, called an alembic, together with its receiver. 

 The alembic here represented is made in one piece, but not uncom- 

 monly the head was movable, as in Fig. 32, where A is the body of 



the alembic, B the 

 movable head, 

 sometimes in old 

 books of chemis- 

 try called "the 

 Moore's head," 

 c the conduct- 

 ing tube ("the 

 nose of the 

 Moore's head"); 

 E the receiver. 

 When the sub- 

 stances to be dis- 

 tilled had been 

 introduced into 

 FlG . 32t the body A, the 



neck of the 



" Moore's head " was dropped into its place at F, and if necessary, 

 the juncture was sealed by a lute of clay or other substance. At the 

 conclusion of the operation the head was separated, and thus the 

 residuum in the body A could easily be removed, as well as any sub- 

 limed solids which might have condensed in the head B, while the 

 receiver E would contain the volatile liquids. 



