64 EXPLOITATION OF THE MARITIME PINE. 



At this time he covers up the upper opening entirely, but without 

 hindering altogether the entrance of air and the issue of smoke : 

 small apertures being indispensable. On the other hand, much air 

 must not be admitted during the night, as then the moisture in the 

 wood is entirely evaporated, and the charcoal powder may be 

 converted into ashes. 



"The carbonisation is completely finished when the workman 

 returns to his kiln on the following morning. Although the kiln has 

 not been hermetically sealed during the night there is but a slight 

 loss of charcoal ; the upper part only being affected by the air which 

 is moveover surcharged with carbonic acid. 



"The workman now hastens to withdraw the charcoal, and to 

 extinguish it as completely as possible. 



" By the lateral opening, he, with a little iron rake, draws out 2 

 hectolitres on to the inclined plane ; he then shuts the opening 

 instantly, and extinguishes the burning powder by watering it with 

 a gardener's watering pan. He applies one litre of water to the 

 hectolitre of powder ; this quantity is not enough to extinguish it 

 completely, but it is known that the powder is of better quality when 

 subjected to roulage, instead of employing an operation to be 

 immediately described, than it would be if more water were employed. 

 The workman then takes a wooden rake and spreads the charcoal 

 over an extent of about ten mi^tres. The charcoal is extinguished 

 all the sooner by coming in contact with the cold earth, and an 

 atmosphere composed of carbonic acid and steam. By this roulage 

 the powder is exposed to the air in thin layers. The workman being 

 careful to extinguish any sparks of fire. 



" This operation is long and hurtful to the workman, he breathes 

 a dry powder which incites him to drink, and injures his lungs. The 

 workmen who drink abundantly of the bad water of the country often 

 fall victims to fever, 



"A workman spends three hours in extinguishing by roulage 

 20 hectolitres of powder. 



" The kiln of the Couscaudiere consumes in a summer day, when 

 supplied by two workmen, from 350 to 360 bourrees, and when 

 supplied by only one workman, 260 or 280 ; 360 bourrees yield from 

 18 to 22 hectolitres of powder, which contain braise in the proportion 

 of 6 to 15. 



" This braise is separated from the powder by an iron sieve, the 

 interstices being 2 centimetres across. The yield of braise varies 

 according to the composition of the bourrees. The oak yields more 

 than the birch, and the latter more than the maritime pine. 



