6 BULLETIN 769, U. S. DEPARTMENT OF AGRICULTURE. 
Unfortunately the statistics on the fat and oil situation in the 
United States in recent years are not entirely complete, so that it 
was necessary to make some assumptions in the compilation of these 
tables. In Tables 1 and 2 the productions given are those reported 
to the Food Administration by a large number of oil manufacturers, 
but it has been difficult to secure proper returns in some cases, and 
undoubtedly many of the smaller oil mills and slaughter houses have 
been overlooked. It is felt, however, that these figures are at least 
95 per cent correct. 
In Tables 4 and 5 the weight hi pounds of some of the vegetable 
oils is calculated from the amount in gallons, as reported by the 
Customs Service, assuming the trade weight of a gallon of all oils 
except olive to be 7.5 pounds, and that of olive oil to be 7.56 pounds. 
The total fat and oil produced in the United States as given in Table 3 
includes the butter fat in factory and farm butter. As the average fat 
content of butter was assumed to be about 83 per cent, the figures in 
this table represent only 83 per cent of the total butter production as 
reported by the Dairy Division of the U. S. Department of Agricul- 
ture. It is obvious that these grand totals do not include nearly all 
of the fat or oil in this country, as in milk alone an immense quan- 
tity of butter fat is consumed. Cheeses also are rich in this fat, con- 
taining from 30 to 35 per cent, and olives, some grains, nuts, and 
especially meats add very largely to the supply of food fats. From 
a technical point of view, however, when we have covered the pure 
fats and oils and butter we have included all products used primarily 
as fats or oils in the dietary and for manufacturing purposes. 
It is very difficult to compare our domestic production of fats and 
oils with the available data on exports and imports, as there is some- 
times a wide variation between the meaning of a term applied to some 
of our imports in this country and its meaning in the country of 
origin. For example, according to our use of the term "foots," olive 
oil foots should be a soap containing some free oil obtained as a by- 
product in refining the oil, but it is really olive oil extracted by a 
solvent from the waste pomace left after the virgin oil has been 
expressed. It therefore falls into the class of primary products, and 
is not a derivative substance, or secondary product. 
To account for the entire exportation of fats from this country we 
must consider the quantity of butter and lard substitutes which are 
shipped, and perhaps also soaps, lubricating greases, and other man- 
ufactured articles. A statement of our importations of fats and oils 
should include the quantity of oil-bearing materials, such as flax- 
seed, copra, soy beans, and peanuts. While these are discussed in 
the sections dealing with the particular oils, it is difficult in many 
instances to determine just how much of the material imported is 
