•386 PROCEEDINGS OF THE OHIO ACADEMY OF SCIENCE. 



workers in other fields of science has transformed products that 

 formerly were not only useless but often a source of expense 

 to the manufacturer into products of great commercial value — 

 as illustrated, for example, in the development of the cottonseed 

 oil industry, the last phase of which consists in transforming 

 the oil into solid fats of high food value. He has devised meth- 

 ods for extracting the rare metals from their ore and has brought 

 them into the service of mankind as illustrated in the revolution 

 brought about in our methods of artificial lighting through the 

 use of cerium and thorium in the construction of gas mantles 

 and of tungsten in the construction of the filaments used in in- 

 candescent lights. By utilizing the electric current as a means 

 for producing high temperatures as well as for effecting chemical 

 •changes he has been able not only to lower the cost of the produc- 

 tion of certain metals from their ores but he has also greatly 

 improved the processes for the manufacture of such important 

 products as caustic soda, chlorine, graphite, calcium carbide and 

 •carborundum. He has devised processes by means of which 

 nitrogen is taken from the air and built up into compounds that 

 can be assimilated by plants thus making us independent of 

 nature's supply of nitrates. He has produced alloys possessing 

 almost any desired properties and dyes and pigments of every 

 imaginaljle color. He has contributed his share to the solution 

 of the problem of preserving health in various ways, such as 

 by devising methods for purifying water supplies, for disposing 

 of sewage, by pointing out the kinds and amounts of foods that 

 are best adapted for the different conditions of life, by substitu- 

 ting the non-poisonous materials for the poisonous and by 

 synthesizing compounds of the greatest service for combating 

 diseases. In these and in hundreds of other ways the chemist 

 lias contributed his share to the development of the arts of 

 peace. However, he has also played his part in the develop- 

 ment of the arts of war. The different alloys of steel that have 

 made the modern engines of war possible, the high explosives, 

 the poisonous gases — for these and many other engines of 

 destruction we have to thank the chemist. There is hope that 

 ere long his contribution to the arts of war will be such as to 



