the linoleic acid to oleic and then the oleic into stearic. If you
figured up the weights from the symbols given above you would find that
it takes about one pound of hydrogen to convert a hundred pounds of
olein to stearin and the cost is only about one cent a pound. The nickel
is unchanged and is easily separated. A trace of nickel may remain in
the product, but as it is very much less than the amount dissolved when
food is cooked in nickel-plated vessels it cannot be regarded as
harmful.

Even more unsaturated fats may be hydrogenated. Fish oil has hitherto
been almost unusable because of its powerful and persistent odor. This
is chiefly due to a fatty acid which properly bears the uneuphonious
name of clupanodonic acid and has the composition of C_{18}H_{28}O_{2}.
By comparing this with the symbol of the odorless stearic acid,
C_{18}H_{36}O_{2}, you will see that all the rank fish oil lacks to make
it respectable is eight hydrogen atoms. A Japanese chemist, Tsujimoto,
has discovered how to add them and now the reformed fish oil under the
names of "talgol" and "candelite" serves for lubricant and even enters
higher circles as a soap or food.

This process of hardening fats by hydrogenation resulted from the
experiments of a French chemist, Professor Sabatier of Toulouse, in the
last years of the last century, but, as in many other cases, the Germans
were the first to take it up and profit by it. Before the war the copra
or coconut oil from the British Asiatic colonies of India, Ceylon and
Malaya went to Germany at the rate of $15,000,000 a year. The palm
kernels grown in British West Africa were shipped, not to Liverpool, but
to Hamburg, $19,000,000 worth annually. Here the oil was pressed out and
used for margarin and the residual cake used for feeding cows produced
butter or for feeding hogs produced lard. Half of the copra raised in