PETKOLEUM. 
45 
ciple is the matter to which emphasis is called. “ Cracking ” is the 
leading potentiality in petroleum refining, no less so because it per- 
mits the production of the other main products according to demand, 
without sacrifice of by-product possibilities. 1 The importance of the 
whole matter may be evalued by having regard to the fact that at 
present, even with “ cracking ” well launched into practice, less than 
one-half of the petroleum produced is manufactured into products 
representing an ideal apportionment 2 of the raw material into its 
components. 3 The production of gasoline may be doubled eventually 
or even more greatly multiplied without increasing the production of 
crude petroleum. 4 
The internal-combustion engine of the type currently in use in the 
United States has been the subject of greater refinements in special 
qualities — luxury qualities — than in respect to efficiency. That is 
evidenced in the widely varying gasoline consumption on the part 
of the familiar brands of automobile motors, which show a range 
from 20 miles and more to the gallon down to a yield of only 6 or 8 
miles in the case of high-price cars. While the sacrifice of efficiency 
in favor of special qualities is, perhaps, legitimate to a certain degree, 
it would appear that the desire for invidious distinction has led to 
an undue focus of attention away from utility. With the rigors 
born of resource limitation — a certain eventuality — and upon the 
passing of the automobile more fully from the realm of a luxury into 
that of a necessity, a greater and more universal reach toward motor 
efficiency may confidently be counted on. But improvements in mo- 
tor design will not lie along the single line of gaining more energy 
from gasoline ; the effective use of heavier petroleum distillates, such 
as kerosene 5 and fuel oil, and of other liquid fuels, such as alcohol, 
benzol, and tar oil, will be planned for and the broad trend of motor 
development will shape toward the character of the resource in its 
1 It should be clearly held in mind that “ cracking,” with its attendant by-product 
possibilities, is a matter in constant course of development. The Bureau of Mines is 
actively engaged in furthering research and experimentation along those lines, though 
progress is hampered by inadequate financial resources. 
2 An ideal apportionment can not be attained so long as there is an overproduction of 
crude petroleum in respect to the demand for gasoline and other motor fuel, kerosene, 
and lubricating oil, and there remains an economic demand for such an overproduction. 
Hence the extent to which “ cracking ” may be applied is, of course, limited by economic 
factors. 
3 “ We are to-day efficients — that is, for gasoline and lubricating purposes — not 
more than 30 per cent of our oils. The other 70 per cent is used in competition with 
coal or exported for foreign countries and is generally sold for less than cost of pro- 
duction.” Yearbook of the Bureau of Mines, 1916, Washington, 1917, p. 133. 
4 “ Cracking ” brings in the asphaltic oils as effective producers of gasoline, a fact of 
no small economic significance. 
5 “ Perhaps no phase of the fuel situation has so interested automotive engineers as the 
use of kerosene in place of gasoline. Present market conditions are such that kerosene 
is one of the cheaper petroleum products, and as it has already been demonstrated to 
woi'k satisfactorily in internal-combustion engines under certain conditions, there has 
been a great desire to render it available for general use in automobiles. The Bureau 
of Mines has had called to its attention many devices for the utilization of kerosene, 
but believes that mechanical development in this particular line is a mistake. The 
logical and reasonable way to utilize kerosene is not as such, but as a mixture with 
