PRESENT PROBLEMS 691 



they are easily revived. A dry culture similar to a yeast-cake, and 

 of about the same size, can thus be sent out and used to prepare 

 a fluid in which the original nitrogen-fixing bacteria may be multi- 

 plied sufficiently to inoculate a number of acres of land. The amount 

 of material thus obtained is limited only by the quantity of the 

 nutrient water-solution used in increasing the germs. Field experi- 

 ments have shown the wonderful activity of these bacteria in fix- 

 ing atmospheric nitrogen and the splendid crops which may be 

 gro\vn upon what would otherwise be almost sterile soil. 



In this one problem of our future supply of available nitrogen 

 for agriculture as well as general manufacturing purposes, we note 

 the aid which technical chemistry draws from the other depart- 

 ments of natural science. The electrical engineer and biologist 

 have already contributed a great share in its solution. There re- 

 mains, however, no small amount of work for the technical chemist 

 to perform before the desired end is reached. 



In an address on "Chemical Problems of To-day," delivered by 

 Victor Meyer in 1889, the author pointed out that, although the 

 synthesis of starch from carbon dioxide and water was a result not 

 to be expected in the near future, yet, he says, "we may reason- 

 ably hope that chemistry will teach us to make the fiber of wood 

 the source of human food." While we do not consider that this is 

 a problem of technical chemistry for the present, the possible use 

 of cellulose as a raw material from which to make food, renders 

 more acute a problem which is to-day clamoring for solution, namely, 

 the preservation of our forests. The influence which the forests of 

 a country have upon its civilization is a topic which has been much 

 discussed of late. That there is an intimate relation between the 

 woodland of a district and the regularity of its rainfall, the absence 

 of floods and freshets, and the general climatic conditions, there 

 seems now to be little doubt. But the consumption of forest products 

 continues to increase far out of proportion to the growth of new 

 timber. The substitution of other raw material in chemical industries 

 which now use wood for this purpose becomes, therefore, an economic 

 problem for the solution of which the chemist is held responsible. 



The production of cellulose from raw materials other than wood 

 is the first important factor in the chemical side of the question. 

 The weight of wood consumed for the production of chemical fiber 

 for the year 1902 was something over two million tons, while one and 

 a half million tons w T ere used for the manufacture of ground wood- 

 pulp. While from some points of view our American forests are 

 sufficient to supply the demand for many years to come, it does not 

 excuse us for the terrible waste of cellulose in forms other than 

 wood, which we are constantly suffering. 



On our flax-fields of the West we are annually burning thousands 



