REPORT OF THE DIRECTOR AND STATE GEOLOGIST 1903 55 



cal to about two-thirds its hight and conical the upper third. 

 It rests upon an iron bed plate containing a rectangular opening 

 over whicli iron bars are laid to form a grate. The bed plate 

 rests upon a chamber of brickwork open at the top and in front, 

 where it can be closed by a door; the floor of the chamber is 

 inclined from back to front. This chamber is intended for a 

 fireplace for wood fuel. Peats are carefully laid over the grate 

 so as not to stop the draft upwards from the fireplace. The 

 kiln is then filled through the top and wood fire is made in the 

 fireplace. After the peat becomes well ignited, the fireplace 

 is closed by an iron door. The peat gradually becomes 

 heated to redness and shrinks about one-third in volume, fresh 

 peat is now thrown in at the top. and this course is repeated 

 until the entire contents of tbe kiln become red-hot. As soon 

 as smoke ceases to escape, the top is covered with an iron plate 

 and the contents of the kiln are allowed to cool." Charcoal 

 made in this way however is found to be very brittle, and there 

 is great loss owing to combustion of the lower part and the 

 formation of much dust and slack. 



An oven for charring peat by a down draft rather than by 

 upward draft, w^as invented by Hahnemann. This oven con- 

 sisted of a circular shaft of brick or stone work IG feet high and 

 7 feet in diameter in the clear. The walls gradually diminish in 

 thickness from 2 feet at the bottom to 10 inches at the top. 

 The shaft rests upon a solid foundation, the floor is somewhat 

 arched with a convexity upwards, and on one side is an opening 

 for withdrawing the charcoal. In the circumference of the 

 floor is a gutter of glazed tiles, from which a glazed clay pipe 

 passes with a slight inclination downwards through the wall 

 and communicates with a tank for the reception of any liquid 

 which may be condensed. On the middle of the floor stands a 

 vertical clay pipe glazed internally, 19 feet high and 16 inches 

 wide, and in which, near and around its base, are seA^eral holes, 

 the total area of which should at least equal the cross-section of 

 the pipe. Before charging, the opening at the bottom of the 



