COLLECTION OP RESIN. 55 



is only performed between the 1st March and 15th October, but the 

 bark may be begun to be removed from the 10th January. A pine 

 gemmi a vie yields about three litres, or quarts of gemme when at its 

 best, that is to say when its diameter is a least forty centimetres. 

 It may also be alleged that taking into account the decreasing num- 

 ber of trees a hectare yields nearly a cask of 340 litres of resin 

 yearly, whatever the age of the trees may be. It is more difficult to 

 reckon the yield of the gemmage ck mort. But it may be admitted 

 that 200 to 250 trees of 20 centimetres in diameter yield about a 

 barrique or hogshead yearly, and that for three years. At Biscarosse 

 I have seen in a wood belonging to M. Marcellus, a pine 4 metres in 

 circumference, and with a bare trunk 11 mfetres high, on which 

 were 4 active quarres, which produced yearly from 7 to 8 litres 

 of resin. 



" The price of resin varies considerably. It is sometimes as low 

 as 40 francs per barrique or hogshead, which is very little. During the 

 American war it rose to 290 francs. 



"At present (1873) raw resin brings 120 francs per barrique at 

 Mont de Marsan, where it is manufactured. The retinier is paid at 

 so much per barrique. His wages vary from 30 to 35 francs, which 

 represents an average day's wage of from 4 to 5 francs. 



" I have visited several manufactories at Mont de Marsan, in one 

 of which essence of turpentine is distilled. It is done thus : the raw 

 resin is put into a large reservoir ; but as it always contains much 

 foreign matter, according to the greater or less care taken in collecting 

 it, earth, chips, bits of bark, leaves, &c. To separate these the raw 

 resin is heated in coppers, taking care that the temperature does not 

 rise so high as to disengage the essence. It is then* filtered through 

 rye straw and received in a trough in a state in which it is called 

 terebenthine. From this trough it passes into an alembic by a valve 

 which opens when necessary. During the distillation a thread of 

 water is introduced by means of a pipe, and this becoming vaporised, 

 it conveys the essence of turpentine along with it through the room, 

 where both are received, in a liquid state, in a bucket, and separation 

 is effected by decantation. 



" What remains in the Alembic is made into resin, dry pitch, and 

 yellow resin. It runs off through an opening below it to a pipe which 

 leads it to a trough. The resin is obtained by filtering it through a 

 very fine brass sieve placed ever a box. Dry pitch is nothing but 

 the residuum, which is at once run into moulds made in fine sand. 

 It is formed into bricks of from 45 to 90 kilogrammes in weight. To 



