2 BULLETIX 1057, L T . S. DEPARTMENT OF AGRICULTURE. 
investigators employed, by intramuscular injection, the ethyl esters 
derived from its peculiar fatty acids. 
In 1918 the Kalihi receiving station 2 invited Dr. A. L. Dean, 
professor of chemistry and president of the University of Hawaii, 
to cooperate in determining which of the constituents of chaul- 
moogra oil possessed specific value in the treatment of leprosy. 
Basing his work upon the exhaustive researches of Dr. Frederick 
B. Power and his collaborators in London (1, 17, 18, 19, 20, 21), 
who first isolated and described the optically active chaulmoogric 
and hydnocarpic acids and prepared their esters, Dr. Dean (6), in 
collaboration with Dr. Richard Wrenshall, undertook the fractiona- 
tion of chaulmoogra oil in order to ascertain the best method of 
preparing the acids and their respective ethyl esters in quantities 
sufficient for clinical use. By means of a high vacuum the acids were 
obtained in a satisfactory degree of purity. 
The standard treatment consisted at first of weekly intramuscular 
injections of the mixed ethyl esters with 2 per cent of iodin in chemi- 
cal combination. These injections were supplemented by the oral 
administration of the fatty acids with 2.5 per cent of iodin, this 
preparation being given in capsules three times a day. 
The method of treatment was later changed by omitting the iodiu 
and also the oral administration of the acids, as it was found that 
this procedure was not necessary and that the injection of the ethyl 
esters was vastly more important. It was furthermore observed 
that the mildest forms of the disease showed the slowest improve- 
ment. One of the difficulties encountered in treating patients is said 
by Drs. McDonald and Dean to be that something like 10 per cent 
of them are unable to take the injections continuously, as they tend 
to break out with swellings, which may be a form of toxemia or an 
anaphylactic reaction. 
While it is a fact that it will require a period of several years to 
demonstrate that persons treated with the ethyl esters of the acids 
obtained from chaulmoogra oil are absolutely cured of leprosy, the 
indications of their curative action after nearly two years of use 
have been so promising as to make a thorough study of the trees 
which furnish this oil and some closely related products extremely 
advisable. That the above-mentioned preparations have been of 
immense help in the treatment of the disease is beyond question. 
McDonald and Dean (16, p. 1473) have, indeed, considered it to be 
established "that the fatty acids of the chaulmoogric series are 
specific in leprosy." 
3 This institution is located in the suburbs of Honolulu,, where for many years those 
auspected of having leprosy were received for examination and whence those affected 
were sent to the leper settlement of Molokai. 
