806 JOFRXAL OF FORESTRY 



the use of grain or molasses for this purpose. One ton of dry conifer- 

 ous sawdust or other form of waste will yield from 15 to 25 gallons of 

 190-proof spirit. 



In brief, the process of producing ethyl alcohol from wood consists 

 in digesting in rotary digesters the sawdust or logged and shredded 

 waste with dilute sulphuric acid at a steam pressure of 60 pounds or 

 more for a short period. The digested material is next transferred to 

 a diffusion battery similar to that used in the extraction of sugar from 

 sugar beets or dyes from dyewoods, and here the sugar and other water 

 soluble material is extracted with hot water from the digested sawdust. 

 The acidity of the extract is then neutralized with lime, and the sludge 

 formed by the calcium sulphate and some of the dust carried in the 

 extract is allowed to settle out, a process requiring from 15 to 24 hours. 

 The clear solutions are then drained off and cooled to the proper tem- 

 perature for fermentation. The fermentation, distillation, and rectifi- 

 cation of the alcohol are accomplished in the usual manner. 



The essential parts of a plant necessary for the production of ethyl 

 alcohol from wood are as follows : Adequate sawdust storage, disinte- 

 grating equipment — hogs, screens, shredders, sawdust storage above 

 digesters, acid storage, digesters, diffusion battery, neutralizing and set- 

 tling tanks, coolers, fermenters and yeast equipment beer still, rectify- 

 ing still, bonded warehouse, boilers and engines, laboratory and office, 



A properly, constructed plant, convenient to an adequate supply of 

 waste wood and with plenty of good water and sulphuric acid easily 

 accessible, and designed to produce from 2,500 to 3,000 gallons a day,, 

 can make ethyl alcohol at a cost of from 14 to 20 cents per gallon, in- 

 cluding all overhead expenses. — American Lumberman, August 4,. 

 1917. 



The Forest Service issues free certain lists in mimeograph form 

 which are of value to those interested in forestry. These are : 



1. "Private foresters and consulting timber and logging experts.'' 

 A list of 22 men or firms who advertise to give advice on forest lands. 



2. Dealers in forest planting material of various kinds of trees. 

 About 40 lists have been prepared giving the names and addresses of 

 nursery men and seed collectors who sell seed, seedlings, or transplants, 

 including cuttings for the production of basket willows. (Those who 

 sell ornamental trees and shrubs only are not put on these lists.) Ap- 

 plicants should give the names of trees in which they are interested. 



3. "Willow-ware manufacturers." This list is intended for basket- 

 willow growers who wish to obtain the names of possible purchasers 

 of willow rods. 



