12 BULLETIN 102, PART 4, UNITED STATES NATIONAL MUSEUM. 
ammonia. The gas had a varying value from a product representing 
the chief source of revenue in some instances down to one giving 
returns too small to justify its storage. 1 The benzol, a few years 
back, was not even recovered, so lacking was any demand for it. 2 
The tar, like the gas, had a considerable though low range in value, 
but until a few years ago it was scarcely profitable to extract it. 
The consequences of inadequate coal-products development in the 
United States have been serious, in some respects critical. Here 
falls entire responsibility for recent shortages in explosives of certain 
types, as well as in dyestuffs, and a variety of drugs and chemicals; 
partial responsibility for the high cost and inadequate supply of 
nitrogen compounds and gasoline; and even a little of the blame for 
the transportation congestion of 1917-18, which industrial coal-gas 
utilization could have alleviated in some measure. These consider- 
ations are apart from wasted materials and wasted opportunities. 
The coal-products situation, indeed, represents one of the most com- 
plex, subtle, and important problems in the whole field of industry 
to-day; and this is true not only in respect to present conditions, 
but also as regards the trend of future industrial growth to a degree 
difficult of full appreciation. The failure of Great Britain to sense 
its importance before the outbreak of the European war came des- 
perately near causing her defeat during the first few months of hos- 
tilities through a lack of toluol; the situation was only saved by the 
happy chance that the British gas industry was developed with 
by-product recovery, and by straining met the emergency. A sim- 
ilar failure on the part of the United States is responsible for some of 
our present embarrassments. A failure to remedy the situation will 
place this country at an unfortunate disadvantage in the future. It 
seems remarkable that a single, partly developed unit of industry can 
have such a vital and far-reaching bearing on the well-being of the 
entire nation, but such is unequivocally true of coal products. That 
fact can not be expressed too plainly or in terms too strong. 
To build a proper coal-products industry, even within the limits 
set by the coke needs of the iron industry, will require the establish- 
ment of a steady demand for the four by-products — gas, ammonia, 
benzol, tar — which will give them a commercial value in keeping with 
their real worth. This, in turn, will depend upon an enlarged utiliza- 
tion of gas for fuel purposes, and the growth of a substantial coal-tar 
industry that to the certain values of the primary products will add 
indefinite constructive possibilities of increased values in a field 
already advanced to the point where warfare, textiles, and chemical 
manufacture are utterly dependent upon it. The whole accom- 
1 It is significant that in 1915 the average cost of city gas was 91 cents per 1,000 cubic feet, while the average 
cost of gas from by-product coke ovens was 10 cents. 
2 And benzol contains toluol, upon an adequate supply of which modem warfare is absolutely dependent. 
