OOTOBKE 28, 1898.] 



SCIENCE. 



573 



ness and diflSculty, while its liberation in 

 the free state takes place always with 

 rapidity and sometimes with explosive vio- 

 lence. 



Some years ago Mr. Stanley Jevons ut- 

 tered a note of warning as to the near ex- 

 haustion of our British coalfields. But the 

 exhaustion of the world's stock of fixed 

 nitrogen is a matter of far greater impor- 

 tance. It means not only a catastrophe 

 little short of starvation for the wheat- eaters, 

 "but indirectly, scarcity for those who exist 

 on inferior grains, together with a lower 

 standard of living for meat-eaters, scarcity 

 of mutton and beef, and even the extinction 

 of gunpowder! 



There is a gleam of light amid this dark- 

 ness of despondency. In its free state 

 nitrogen is one of the most abundant and 

 pervading bodies on the face of the earth. 

 Every square yard of the earth's surface 

 has nitrogen gas pressing down on it to the 

 extent of about seven tons; but this is in 

 the free state, and wheat demands it fixed. 

 To convey this idea in an object-lesson, I 

 may tell you that, previous to its destruc- 

 tion by fire, Colston Hall, measuring 146 

 feet by 80 feet by 70 feet, contained 27 tons' 

 weight of nitrogen in its atmosphere; it also 

 contained one-third of a ton of argon. In 

 the free gaseous state this nitrogen is worth- 

 less; combined in the form of nitrate of 

 soda it would be worth about 2,000L 



For years past attempts have been made 

 to effect the fixation of atmospheric nitrogen, 

 and some of the processes have met with 

 sufficient partial success to warrant experi- 

 mentalists in pushing their trials still 

 further ; but I think I am right in saying 

 that no process has yet been brought to the 

 notice of scientific or commercial men 

 which can be considered successful either 

 as regards cost or yield of product. It is 

 possible, by several methods, to fix a cer- 

 tain amount of atmospheric nitrogen ; but, 

 to the best of my knowledge, no process has 



hitherto converted more than a small 

 amount, and this at a cost largely in excess 

 of the present market value of fixed nitrogen. 



The fixation of atmospheric nitrogen, 

 therefore, is one of the great discoveries 

 awaiting the ingenuity of chemists. It is 

 certainly deeply important in its practical 

 bearings on the future welfare and happi- 

 ness of the civilized races of mankind. This 

 unfulfilled problem, which so far has eluded 

 the strenuous attempts of those who have 

 tried to wrest the secret from Nature, differs 

 materially from other chemical discoveries 

 which are ia the air, so to speak, but are 

 not yet matured. The fixation of nitrogen 

 is vital to the progress of civilized humanity. 

 Other discoveries minister to our increased 

 intellectual comfort, luxury or convenience; 

 they serve to make life easier, to hasten 

 the acquisition of wealth, or to save time, 

 health or worry. The fixation of nitrogen 

 is a question of the not- far-distant future. 

 Unless we can class it among certainties to 

 come, the great Caucasian race will cease 

 to be foremost in the world, and will be 

 squeezed out of existence by races to whom 

 wheaten bread is not the staff of life. 



Let me see if it is not possible even now 

 to solve the momentous problem. As far 

 back as 1892 I exhibited, at one of the 

 Soirees of the Eoyal Society, an experiment 

 on ' The Flame of Burning Nitrogen.' I 

 showed that nitrogen is a combustible gas, 

 and the reason why when once ignited the 

 flame does not spread through the atmos- 

 phere and deluge the world in a sea of 

 nitric acid is that its igniting point is higher 

 than the temperature of its flame — not, 

 therefore, hot enough to set fire to the ad- 

 jacent mixture. But by passing a strong 

 induction current between terminals the air 

 takes fire and continues to burn with a pow- 

 erful flame, producing nitrous and nitric 

 acids. This inconsiderable experiment may 

 not unlikely lead to the development of a 

 mighty industry destined to solve the great 



