CHEMICAL APPARATUS. 



61 



Matrass or Bolt Head. 

 (Fig. 483.) The matrass 

 or bolt head is a globular 

 glass vessel with a narrow 

 long neck, used by chemists in digestions and other opera- 

 tions. Price, gill, $0.25 ; half pint, $0.31. 

 " pint, $0.38 ; quart, $0.50. 



Retort. A chemical instrument, for holding solids or 

 liquids for the purpose of distillation. According to the 

 heat that it is to be submitted to, and the nature of the 

 substance contained, so retorts are of different forms, and 

 made of different materials ; thus for the making of various 

 gases cast-iron retorts are commonly employed. Fluorine 

 requires one of silver or lead. In the manufacture of the 

 acids, earthenware retorts are mostly employed; and for 

 ordinary purposes of distillation, and other chemical ope- 

 rations, glass is the material approved of. 



Glass Retort. (Figs. 484, 485, 486, next page .) Retorts 

 are vessels employed in a variety of distillations, and most 

 frequently for those which require a degree of heat superior 

 to that of boiling water. This vessel is a kind of bottle 

 with a long neck, so bent that it makes with the belly of 

 the retort an angle of about sixty degrees. The most capa- 

 cious part of the retort is called its belly ; its upper part is 

 called the arch or roof of the retort ; and the bent part is 

 the neck. They are made of glass, porcelain, and stone- 

 ware, of a great variety of sizes, plain and with stoppers. 

 The tubulated or stoppered retort has an opening, or tubu- 

 lar, for introducing the materials to be acted upon, and this 

 opening also allows of an addition being made to such 

 materials while the retort is at work. 



Price, flint glass retorts, gill, 



half pint, 

 pint, 

 quart, 

 stoppered, gill, 



" half pint, 



pint, 

 quart, 



$0.25. 

 $0.31. 

 $0.37. 

 $0.50. 

 $0.31. 

 $0.37. 

 $0.44. 

 $0.63. 



VOL. II. 6 



half gall., $0.88. 

 gallon, $137. 



