OF CENTRAL CANADA PART I. 25 



num wire, three or four inches in length, of about the thickness of 

 thin twine, to serve as a sjipport in fusions with borax, &c. (see 

 below) ; two or three small glass flasks, or, in default, a narrow test 

 tube or two, used chiefly for the detection of water in minerals (see 

 below) ; a few pieces of narrow glass tubing, in lengths of four or five 

 inches, open at both ends ; a small hammer and anvil, or piece of 

 hard steel, half-an-inch thick, polished on one of its faces ; a bar or 

 horse-shoe magnet; a pen-knife or small steel spatula; a small agate 

 pestle and mortar; spirit-lamp, &c.; and a few wooden boxes or small 

 stoppered bottles to hold the blowpipe reagents. These latter are 

 employed for the greater part in the solid state, a condition'which 

 adds much to their portability, and renders a small quantity sufficient 

 for a great number of experiments. The principal comprise : Carbon- 

 ate of soda (abbreviated into carb. soda, in the following pages), used 

 largely for the reduction of metallic oxides, and in testing for sulphur 

 and sulphuric acid, manganese, &c., as explained below; Biborate of 

 soda, or Borax, used principally for fusions on the platinum wire, 

 many substances communicating peculiar colours to the glass thus 

 formed ; and Phosphate of soda and ammonia, commonly known as 

 microcosmic salt or phosphor salt, used for the same purpose as borax, 

 and also for the detection of silicates and chlorides, as explained 

 further on. Re-agents of less common use comprise : nitrate of 

 cobalt (in solution) ; bisulphate of potash ; black oxide of copper ; 

 chloride of barium ; metallic tin ; and a few other substances of 

 special employment. 



The effects produced by the blowpipe cannot be properly under- 

 stood without a preliminary knowledge of the general composition 

 and structural parts of Flame. If the flame of a lamp or 

 candle, standing in a place free from draughts, be carefully 

 examined, it will be seen to consist of four more or less 

 distinct parts, as shown in in the annexed diagram, FIG- 

 31. A dark cone, a, will be seen in the centre of the flame. 

 This consists of gases, compounds of carbon and hydrogen, 

 which issue from the wick, but which cannot burn as they 

 are cut off from contact with the atmosphere. A bright 

 luminous cone 6, surrounds this dark central portion, 

 except at its extreme base. In this bright cone the car- 

 bon, or a portion of it, separates from the hydrogen of 



