ve
recognized jecoric acid, C18H30O2, asellic acid, C17H32O2, and
physetoleic acid, C16H30O2, but some uncertainty attends these last
three acids. Therapic and jecoleic acids apparently do not occur
elsewhere in the animal kingdom, and it is probable that the therapeutic
properties of the oil are associated with the presence of these acids,
and not with the small amount of iodine present as was at one time
supposed. Other constituents are cholesterol (0.46-1.32%), traces of
calcium, magnesium, sodium, chlorine and bromine, and various aliphatic
amines which are really secondary products, being formed by the
decomposition of the cellular tissue.

Cod-liver oil is used externally in medicine when its internal
administration is rendered impossible by idiosyncrasy or the state of
the patient's digestion. The oil is very readily absorbed from the skin
and exerts all its therapeutic actions when thus exhibited. This method
is often resorted to in the case of infants or young children suffering
from abdominal or other forms of tuberculosis. Its only objection is the
odour which the patient exhales. When taken by the mouth, cod-liver oil
shares with other liver-oils the property of ready absorption. It often
causes unpleasant symptoms, which must always be dealt with and not
disregarded, more harm than good being done if this course is not
followed. Fortunately a tolerance is soon established in the majority of
cases. It has been experimentally proved that this is more readily
absorbed than any other oil--including other liver-oils. Much attention
has been paid to the explanation of this fact, since knowledge on this
point might enable an artificial product, without the disadvantages of
this oil, to be substituted for it. Very good results have been obtained
from a preparation named "lipanin," which consists of six parts of oleic
acid and ninety-four of pure olein. Cod-liver oil has the further
peculiarity of being more readily oxidizable than any other oil; an
obviously valuable property when it is remembered that the entire
food-value of oils depends on their oxidation.

Cod-liver oil may be given in all wasting diseases, and is occasionally
valuable in cases of chronic rheumatoid arthritis; but its great
therapeutic value is in cases of tuberculosis of whatever kind, and
notably in pulmonary tuberculosis or consumption. Its reputation in this
is quite inexpugnable. It is essential to remember that "in phthisis the
key of t