Iqoj] Wheeler— Problems m Cellulose F*ield. 113 



we consider the vast waste of cellulose in the form of sawdust 

 (acres of it about a single saw mill) the possibilities of a new 

 source of sugar (and from that, alcohol) are extremely inter- 

 esting. 



Cellulose is acquiring a greater and greater importance in 

 the arts and manufactures. Its use as a paper stock and as a 

 raw material for clothing place it in the front rank of indus- 

 trial products. Some of its derivatives also find extensive 

 application, the nitro-celluloses for explosives, artificial silk 

 and celluloid, and the thiocarbonate for artificial silk. The 

 tetracetate has been found to possess insulating powers supe- 

 rior to gutta-percha and it is now a commercial product. If 

 a solution of the acetate is allowed to evaporate a film of 

 great tenacity is obtained which may be used in photography 

 and for laquering metals. An acetate may also be obtained 

 in the form of a powder, soluble in chloroform and nitro- 

 benzol. This is used for preparing substances resembling 

 celluloid and as a substitute for collodion. Its advantages 

 lie in the fact that it is odorless and is not inflammable. Two 

 problems which have not been seriously attacked are the con- 

 ductivity of pure cellulose and the use of cellulose as a mem- 

 brane in osmotic work. Many other questions of varying 

 degrees of importance might be mentioned. 



In concluding this brief survey I wish to express my agree- 

 ment with the idea now often expressed that the demarcation 

 line between the scientific and the practical has hitherto been 

 too sharply drawn. Professor Jordan recently said: "It is 

 often a temptation to distinguish radically between pure 

 science and applied science and to look upon the latter as 

 unworthy the attention of the philosophically minded. True 

 science can admit of no such distinction," and President Jor- 

 dan says, "Applied science can not be separated from pure 

 science, for pure science may develop at any quarter the 

 greatest and most unexpected economic values, while, on the 

 other hand, the applications of knowledge must await the 



