164 FORESTRY INVESTIGATIONS U. S. DEPARTMENT OP AGRICULTURE. 



worked profitably four or five times as long as under present methods, and hence many precau- 

 tions, especially against fire, such as ditches, roads, etc., to arrest the fire, too expensive if the 

 orchard is soon to be abandoned, may be employed with advantage. 



(9) If present methods must prevail and protection against fires can not be had, because the 

 community is still too uncivilized or blind to its interests, do not subject your valuable timber to 

 turpentine orcliaiding unless you can dispose of it to a sawmill immediately after the orchard is 

 abandoned. Otherwise the loss of timber by fire is apt to wipe out all profits made by the orchard. 



IMPROVEMENTS IN THE DISTILLA1TON 01 THE CRUDE TURPENTINE BY THE APPLICATION OF STEAM. 



In the ordinary way, the distillation of the crude turpentine, yielding the largest quantity of 

 spirits of turpentine and finest quality of rosin, can not be carried to the total extraction of the 

 volatile oil without impairing the quality of the residuary product. The higher grades of rosin 

 are still retaining a considerable amount of spirits. To prevent such loss distillation by steam 

 has been resorted to. This innovation seems, however, not to have received the deserved attention. 

 From the latest information it appears that this method has proved completely successful at a 

 turpentine distillery in ^ew Orleans; there, by its introduction, an increase of fully 30 per cent is 

 claimed over the yield of spirits of turpentine obtained by distillation with the open fire, the grade 

 of rosin remaining unaffected. 



PRODUCTS OF 'I HE DESTRUCTIVE DISTILLATION OF THE WOOD OF THE LONGLEAF PINE. 



The air-dried wood of the longleaf pine in its normal condition has been found to contain from 

 2 to 2g per cent of volatile oil, taking the specific gravity of spirits of turpentine at 0.87 and the 

 weight of 1 cubic foot of the air-dried wood at 43 pounds. The spirits is obtained by subjecting 

 the wood to the action of superheated steam in the same retorts in which its destructive distilla- 

 tion is carried on, a process with which its production direct from the wood is invariably connected, 

 and of which it forms the first step. The quantity of spirits of turpentine obtained varies largely. 

 As stated by one operator, it differs all the way from 5 to 18 per cent, according to the wood being 

 fresh cut or dry, and to the different parts of the tree from which it is taken. From the results of 

 numerous experiments made on a large scale in different parts of the longleaf-pine region, it can 

 be assumed that 1 cord of wood, green and of different degrees of dryness, yields, on the average, 

 about 15 gallons of an impure spirits of turpentine. Owing to the presence of empyreumatic 

 substances of yellow color it becomes darker on exposure to air and of an empyreumatic odor. It 

 is easily freed from its impurities by redistillation; thus rectified, the product is perfectly clear, 

 colorless, and almost odorless, save a faint woody smell, answering all the purposes for which the 

 spirits of turpentine obtained from the rosin is used. In 1881 Mr. William Mepan, of Georgia, 

 secured a patent for the utilization of the wood wasted at the sawmills, of the refuse left on the 

 ground in the logging camp and in the turpentine orchard, for the production of spirits of turpen- 

 tine, pyroligneous acid, tar, and charcoal. By the operation of the apparatus of the patentee, on 

 exhibition at the Atlanta International Exposition (in 1882), 600 pounds of dry, highly resinous 

 wood, so-called lightwood, yielded — 



Pounds. 



Spirits of tui pontine , 21J- 



Pyroligneous acid 95 



Hea\y oilh and tar 150 



Charcoal 127 



Water and gas 206! 



Total 600 



Amounting to a yield by the cord of 24 gallons of spirits of turpentine, 88 gallons of pyrolig- 

 neous acid, 120 gallons tarry and heavier oily products, and 56 bushels of charcoal. 1 



In several experiments made at the same place slabs taken from the sawmill yielded (to the 

 cord) from 12 to 14 gallons of spirits of turpentine, 200 to 250 gallons of weak pyroligneous acid, 

 from 04 to 108 gallons of tar and heavier oils, and from 50 to 60 bushels of charcoal. The opera- 

 tions subsequently carried on by the same parties in retorts of a capacity of about 6 cords of 



Report of awards at the Atlanta International Exposition in 1882. 



